The chemical constituents of volatile oils used in traditional Chinese medicine are highly complex. Thus, achieving the complete separation of volatile oils by one-dimensional chromatography is difficult owing to the low peak capacity of the technique. Although comprehensive two-dimensional gas chromatography provides an efficient means for separating volatile oils, it cannot be used to screen bioactive components because of its limitations. Therefore, developing a new method to separate volatile oils based on liquid chromatography is of great significance in efforts to obtain new approaches to screen bioactive components in volatile oil. The objectives of the present study are to establish an efficient method for separating the chemical constituents of Curcuma volatile oil using off-line comprehensive two-dimensional countercurrent chromatography-liquid chromatography (CCC-LC) and to investigate the two-dimensional peak capacity, orthogonality, and spatial coverage of this method. Both CCC and LC conditions were optimized. A biphasic n-hexane-methanol-water solvent system was selected via the colorimetric method, and the lower phase was used as the mobile phase in gradient-elution mode: 0-55 min, n-hexane-methanol-water (5∶2∶3 v/v/v); 55-170 min, n-hexane-methanol-water (5∶3∶2, v/v/v); 170-290 min, n-hexane-methanol-water (5∶4∶1, v/v/v). After gradient elution, elution-extrusion elution mode was applied within 290-375 min. Good resolution was achieved by the CCC separation process. The HPLC separation process was carried out with gradient elution using a mobile phase composed of acetonitrile (A)-water (B): 0-10 min, 50%A-65%A; 10-14 min, 65%A; 14-21 min, 65%A-85%A; 21-25 min, 85%A-95%A; 25-30 min, 95%A-55%A; 30-40 min, 55%A. Curcuma volatile oil was separated under the above optimized two-dimensional separation conditions, and the data obtained were drawn into a two-dimensional contour map using Matlab software. The calculated total peak capacity exceeded 954, which was 10 times more than that of one-dimensional chromatography. High orthogonality (r=0.17) and spatial coverage factor (68.1%) were also obtained. Our research provides a new methodology for separating volatile oils used in traditional Chinese medicine as well as an approach for evaluating the quality of traditional Chinese medicinal herbs using two-dimensional chromatographic fingerprints.
{"title":"[Off-line comprehensive two-dimensional countercurrent chromatography-liquid chromatography separation of <i>Curcuma</i> volatile oil].","authors":"Xin Tong, Yang Jin, Jing Jin, Ping Liu, Chunyan Wu, Shengqiang Tong","doi":"10.3724/SP.J.1123.2023.04008","DOIUrl":"https://doi.org/10.3724/SP.J.1123.2023.04008","url":null,"abstract":"<p><p>The chemical constituents of volatile oils used in traditional Chinese medicine are highly complex. Thus, achieving the complete separation of volatile oils by one-dimensional chromatography is difficult owing to the low peak capacity of the technique. Although comprehensive two-dimensional gas chromatography provides an efficient means for separating volatile oils, it cannot be used to screen bioactive components because of its limitations. Therefore, developing a new method to separate volatile oils based on liquid chromatography is of great significance in efforts to obtain new approaches to screen bioactive components in volatile oil. The objectives of the present study are to establish an efficient method for separating the chemical constituents of <i>Curcuma</i> volatile oil using off-line comprehensive two-dimensional countercurrent chromatography-liquid chromatography (CCC-LC) and to investigate the two-dimensional peak capacity, orthogonality, and spatial coverage of this method. Both CCC and LC conditions were optimized. A biphasic <i>n</i>-hexane-methanol-water solvent system was selected via the colorimetric method, and the lower phase was used as the mobile phase in gradient-elution mode: 0-55 min, <i>n</i>-hexane-methanol-water (5∶2∶3 v/v/v); 55-170 min, <i>n</i>-hexane-methanol-water (5∶3∶2, v/v/v); 170-290 min, <i>n</i>-hexane-methanol-water (5∶4∶1, v/v/v). After gradient elution, elution-extrusion elution mode was applied within 290-375 min. Good resolution was achieved by the CCC separation process. The HPLC separation process was carried out with gradient elution using a mobile phase composed of acetonitrile (A)-water (B): 0-10 min, 50%A-65%A; 10-14 min, 65%A; 14-21 min, 65%A-85%A; 21-25 min, 85%A-95%A; 25-30 min, 95%A-55%A; 30-40 min, 55%A. <i>Curcuma</i> volatile oil was separated under the above optimized two-dimensional separation conditions, and the data obtained were drawn into a two-dimensional contour map using Matlab software. The calculated total peak capacity exceeded 954, which was 10 times more than that of one-dimensional chromatography. High orthogonality (<i>r</i>=0.17) and spatial coverage factor (68.1%) were also obtained. Our research provides a new methodology for separating volatile oils used in traditional Chinese medicine as well as an approach for evaluating the quality of traditional Chinese medicinal herbs using two-dimensional chromatographic fingerprints.</p>","PeriodicalId":9864,"journal":{"name":"色谱","volume":"41 12","pages":"1115-1120"},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10719806/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138797516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
<p><p>The complex matrix of soil samples and low extraction efficiency of aniline compounds limit many methods developed for detecting aniline and benzidine compounds in soil. In this study, a rapid and sensitive method based on gas chromatography-mass spectrometry was developed for the simultaneous determination of 14 aniline and benzidine compounds in soil. The collected soil samples were sealed with 5% sodium sulfite solution and refrigerated to inhibit the oxidation of the target compounds for up to 7 d. The extraction efficiencies of accelerated solvent extraction and oscillating dispersion extraction were compared, and the recovery of accelerated solvent extraction was found to be unsuitable. Hence, three-phase oscillating dispersion extraction was adopted. A certain amount of alkaline aqueous solution was added to the test system during extraction to improve the extraction efficiency because aniline and benzidine compounds are weakly alkaline substances. When the pH of the extracted water phase was greater than 12, relatively good recoveries were obtained. Next, a mixed solvent of ethyl acetate-methylene chloride (1∶4, v/v) was added to extract the target compounds via oscillation for 20 min. The solid phase was discarded via centrifugation, and the aqueous and organic phases were transferred to a liquid separation funnel for further separation. Finally, the organic phase was retained. This pretreatment process prevents the co-extraction of acidic compounds or other impurities, thereby enhancing the purification ability of the method. Solid phase extraction (SPE) is generally recommended for soil extraction and purification. A preliminary test showed that compared with other columns, the Florisil SPE column could better retain the target substances and exhibited higher elution efficiency. After purification, the organic phase was concentrated to 1 mL using a nitrogen blower. The analytes were analyzed by gas chromatography-mass spectrometry using a capillary column (DB-35MS, 30 m×0.25 mm×0.25 μm). The temperature program was optimized to separate the target compounds at the baseline. Specifically, the initial oven temperature was set to 60 ℃, held for 2 min, increased to 130 ℃ at a rate of 5 ℃/min, increased to 300 ℃ at a rate of 30 ℃/min, and held for 4 min. The injector and ion source temperatures were 250 and 300 ℃, respectively. Aniline-d<sub>5</sub> and acenaphthene-d<sub>10</sub> were used as the internal standards for quantification. The effects of antioxidant addition, extraction solvent type, salting out, and other factors on extraction efficiency were investigated. The results showed that the method performed well under the optimized experimental conditions when actual soils were used as real sample matrices. The accuracy and precision of the proposed method were verified. A total of 14 aniline and benzidine compounds demonstrated good linearities in the range of 0.5-100 mg/L. The method detection limits (MDLs) ranged from 0.02 t
{"title":"[Determination of 14 aniline and benzidine compounds in soil by gas chromatography-mass spectrometry].","authors":"Lijuan Wu, Lili Yang, Enyu Hu, Meifei Wang, Chao Yang, Mingming Yin","doi":"10.3724/SP.J.1123.2023.01002","DOIUrl":"https://doi.org/10.3724/SP.J.1123.2023.01002","url":null,"abstract":"<p><p>The complex matrix of soil samples and low extraction efficiency of aniline compounds limit many methods developed for detecting aniline and benzidine compounds in soil. In this study, a rapid and sensitive method based on gas chromatography-mass spectrometry was developed for the simultaneous determination of 14 aniline and benzidine compounds in soil. The collected soil samples were sealed with 5% sodium sulfite solution and refrigerated to inhibit the oxidation of the target compounds for up to 7 d. The extraction efficiencies of accelerated solvent extraction and oscillating dispersion extraction were compared, and the recovery of accelerated solvent extraction was found to be unsuitable. Hence, three-phase oscillating dispersion extraction was adopted. A certain amount of alkaline aqueous solution was added to the test system during extraction to improve the extraction efficiency because aniline and benzidine compounds are weakly alkaline substances. When the pH of the extracted water phase was greater than 12, relatively good recoveries were obtained. Next, a mixed solvent of ethyl acetate-methylene chloride (1∶4, v/v) was added to extract the target compounds via oscillation for 20 min. The solid phase was discarded via centrifugation, and the aqueous and organic phases were transferred to a liquid separation funnel for further separation. Finally, the organic phase was retained. This pretreatment process prevents the co-extraction of acidic compounds or other impurities, thereby enhancing the purification ability of the method. Solid phase extraction (SPE) is generally recommended for soil extraction and purification. A preliminary test showed that compared with other columns, the Florisil SPE column could better retain the target substances and exhibited higher elution efficiency. After purification, the organic phase was concentrated to 1 mL using a nitrogen blower. The analytes were analyzed by gas chromatography-mass spectrometry using a capillary column (DB-35MS, 30 m×0.25 mm×0.25 μm). The temperature program was optimized to separate the target compounds at the baseline. Specifically, the initial oven temperature was set to 60 ℃, held for 2 min, increased to 130 ℃ at a rate of 5 ℃/min, increased to 300 ℃ at a rate of 30 ℃/min, and held for 4 min. The injector and ion source temperatures were 250 and 300 ℃, respectively. Aniline-d<sub>5</sub> and acenaphthene-d<sub>10</sub> were used as the internal standards for quantification. The effects of antioxidant addition, extraction solvent type, salting out, and other factors on extraction efficiency were investigated. The results showed that the method performed well under the optimized experimental conditions when actual soils were used as real sample matrices. The accuracy and precision of the proposed method were verified. A total of 14 aniline and benzidine compounds demonstrated good linearities in the range of 0.5-100 mg/L. The method detection limits (MDLs) ranged from 0.02 t","PeriodicalId":9864,"journal":{"name":"色谱","volume":"41 12","pages":"1127-1134"},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10719804/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138797571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-01DOI: 10.3724/SP.J.1123.2023.04002
Kun Mi, Wentian Zhang, Luhong Wen, Jin Wang
<p><p>Amphetamine-type drugs are synthetic compounds with an amphetamine parent structure. These compounds cause addiction, central nervous system excitation, and hallucinations. The number of drug users worldwide has gradually increased because amphetamine-type drugs can be synthesized in a simple and artificial manner. The current methods for anti-drug screening and toxicant identification are limited by the large quantity and variety of the drug analytes and long detection times. Thus, the development of broad-spectrum, rapid, and high-throughput detection methods is an urgent necessity. In addition, conventional amphetamine-type drug test samples, such as blood and urine, are only suitable for short-term drug identification. Hair has the advantages of easy preservation, stability, and a long detection window, which can compensate for the deficiencies of body-fluid-based test materials. Hair samples can reflect long-term drug use, which is beneficial for tracing drug sources, and has become an important means of providing evidence in court. Because most laboratory instruments are unable to perform the rapid on-site detection of amphetamine-type drugs in hair, establishing a high-throughput, qualitative and quantitative rapid on-site detection method is necessary. In this study, pulsed direct current electrospray ionization (Pulsed-DC-ESI) coupled with mass spectrometry was used for the rapid detection of four amphetamine-type drugs (amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, and 3,4-methylenedioxymethamphetamine) in hair. Methanol was used as the extraction solvent, and the grinding method was used for extraction. The pretreatment process included cutting, grinding, and centrifugation. The pretreatment time for each sample was about 10 min. Multiple samples could be processed in batches, greatly improving the efficiency of analysis. Pulsed-DC-ESI is an ambient ionization technology that can be conducted via direct injection without chromatographic separation. The tip of the spray capillary tube was immersed 1 cm below the surface of the sample solution to allow absorption via the capillary effect. When the spray capillary tube contained 1 μL of the sample solution, detection was performed. Pulsed-DC-ESI generates an electrospray at the same frequency as the mass spectrum, thereby avoiding the problem of sample wastage, which often occurs in traditional ESI. The portable mass spectrometer used for analysis is a linear ion trap mass spectrometer. The parameters of Pulsed-DC-ESI, such as the inner diameter of spray capillary tip, spray voltage, and distance between electrode and solution, were optimized based on the mass spectral responses of the amphetamine-type drugs. The optimized ion source conditions included a inner diameter of spray capillary tip of 25 μm, spray voltage of 2 kV, and the distance between electrode and solution of 20 mm. The optimal sample solvent was methanol. The optimized method can achieve simultaneous
{"title":"[Rapid detection of four amphetamine-type drugs in hair by pulsed direct current electrospray mass spectrometry].","authors":"Kun Mi, Wentian Zhang, Luhong Wen, Jin Wang","doi":"10.3724/SP.J.1123.2023.04002","DOIUrl":"https://doi.org/10.3724/SP.J.1123.2023.04002","url":null,"abstract":"<p><p>Amphetamine-type drugs are synthetic compounds with an amphetamine parent structure. These compounds cause addiction, central nervous system excitation, and hallucinations. The number of drug users worldwide has gradually increased because amphetamine-type drugs can be synthesized in a simple and artificial manner. The current methods for anti-drug screening and toxicant identification are limited by the large quantity and variety of the drug analytes and long detection times. Thus, the development of broad-spectrum, rapid, and high-throughput detection methods is an urgent necessity. In addition, conventional amphetamine-type drug test samples, such as blood and urine, are only suitable for short-term drug identification. Hair has the advantages of easy preservation, stability, and a long detection window, which can compensate for the deficiencies of body-fluid-based test materials. Hair samples can reflect long-term drug use, which is beneficial for tracing drug sources, and has become an important means of providing evidence in court. Because most laboratory instruments are unable to perform the rapid on-site detection of amphetamine-type drugs in hair, establishing a high-throughput, qualitative and quantitative rapid on-site detection method is necessary. In this study, pulsed direct current electrospray ionization (Pulsed-DC-ESI) coupled with mass spectrometry was used for the rapid detection of four amphetamine-type drugs (amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, and 3,4-methylenedioxymethamphetamine) in hair. Methanol was used as the extraction solvent, and the grinding method was used for extraction. The pretreatment process included cutting, grinding, and centrifugation. The pretreatment time for each sample was about 10 min. Multiple samples could be processed in batches, greatly improving the efficiency of analysis. Pulsed-DC-ESI is an ambient ionization technology that can be conducted via direct injection without chromatographic separation. The tip of the spray capillary tube was immersed 1 cm below the surface of the sample solution to allow absorption via the capillary effect. When the spray capillary tube contained 1 μL of the sample solution, detection was performed. Pulsed-DC-ESI generates an electrospray at the same frequency as the mass spectrum, thereby avoiding the problem of sample wastage, which often occurs in traditional ESI. The portable mass spectrometer used for analysis is a linear ion trap mass spectrometer. The parameters of Pulsed-DC-ESI, such as the inner diameter of spray capillary tip, spray voltage, and distance between electrode and solution, were optimized based on the mass spectral responses of the amphetamine-type drugs. The optimized ion source conditions included a inner diameter of spray capillary tip of 25 μm, spray voltage of 2 kV, and the distance between electrode and solution of 20 mm. The optimal sample solvent was methanol. The optimized method can achieve simultaneous ","PeriodicalId":9864,"journal":{"name":"色谱","volume":"41 12","pages":"1141-1148"},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10719801/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138797659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
<p><p>The cardinal clinical features of Parkinson's disease (PD), a common neurodegenerative disease, include the irreversible impairment of movement coordination, such as tremors, gait rigidity, bradykinesia, and hypokinesia. Although various factors are associated with the pathological changes in PD, such as oxidative stress, mitochondrial dysfunction, and neuroinflammation, the availability of treatments to retard PD progression is limited. Therefore, novel biomarkers for PD diagnosis and therapeutic targets are urgently needed. The diagnosis of PD mainly depends on its clinical manifestations and has an error rate of approximately 20%. Studies have shown that <i>α</i>-synuclein (<i>α</i>-syn) levels are significantly increased in the cerebrospinal fluid of patients with PD; however, the invasive nature of lumbar puncture restricts further studies on its clinical applications. Hence, the development of novel peripheral blood markers would be helpful for the early diagnosis of PD. Exosomes are extracellular vesicles (EVs) released by various cell types under physiological and pathophysiological conditions. Because exosomes carry a variety of bioactive molecules, they play a key role in biological processes such as intercellular communication and the immune response. Central nervous system (CNS)-derived exosomes can be detected in the cerebrospinal and peripheral body fluids of patients with PD, and their contents are altered during the disease process, rendering them an attractive biomarker resource. Therefore, a comprehensive and high-throughput investigation of the plasma and its exosomes may enhance our understanding of PD. In this study, we isolated exosomes from plasma using standard differential centrifugation and performed tandem mass tag (TMT)-labeled quantitative proteomic analysis of plasma and plasma exosome samples from healthy individuals and patients with PD using liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total of 724 proteins were quantified in the plasma samples, and 611 proteins were screened from the exosome samples. Among these 611 proteins, 413 were found in the Exosomal Protein Database (Exocarta). Using |log<sub>2</sub>FC|>0.26 and <i>P</i>-value (<i>P</i>)<0.05 as the cutoff, five upregulated and six downregulated proteins were identified in the plasma samples of the PD group compared with the healthy group. In the plasma exosome samples, compared with the healthy group, the PD group showed six upregulated and seven downregulated proteins. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted based on gene set enrichment analysis (GSEA). GO-cellular component (CC) analysis revealed that plasma-enriched proteins were mainly located in the nucleus whereas plasma exosome-enriched proteins were mainly located in the cytoplasm. According to the GO-molecular function (MF) analysis, the MFs of differentially expressed proteins in the plasma were mainly enriched in RNA, D
{"title":"[Tandem mass tag-based quantitative proteomics analysis of plasma and plasma exosomes in Parkinson's disease].","authors":"Yuan Zhao, Xin Liu, Yidan Zhang, Jian Zhang, Xiang Liu, Guofeng Yang","doi":"10.3724/SP.J.1123.2022.12022","DOIUrl":"https://doi.org/10.3724/SP.J.1123.2022.12022","url":null,"abstract":"<p><p>The cardinal clinical features of Parkinson's disease (PD), a common neurodegenerative disease, include the irreversible impairment of movement coordination, such as tremors, gait rigidity, bradykinesia, and hypokinesia. Although various factors are associated with the pathological changes in PD, such as oxidative stress, mitochondrial dysfunction, and neuroinflammation, the availability of treatments to retard PD progression is limited. Therefore, novel biomarkers for PD diagnosis and therapeutic targets are urgently needed. The diagnosis of PD mainly depends on its clinical manifestations and has an error rate of approximately 20%. Studies have shown that <i>α</i>-synuclein (<i>α</i>-syn) levels are significantly increased in the cerebrospinal fluid of patients with PD; however, the invasive nature of lumbar puncture restricts further studies on its clinical applications. Hence, the development of novel peripheral blood markers would be helpful for the early diagnosis of PD. Exosomes are extracellular vesicles (EVs) released by various cell types under physiological and pathophysiological conditions. Because exosomes carry a variety of bioactive molecules, they play a key role in biological processes such as intercellular communication and the immune response. Central nervous system (CNS)-derived exosomes can be detected in the cerebrospinal and peripheral body fluids of patients with PD, and their contents are altered during the disease process, rendering them an attractive biomarker resource. Therefore, a comprehensive and high-throughput investigation of the plasma and its exosomes may enhance our understanding of PD. In this study, we isolated exosomes from plasma using standard differential centrifugation and performed tandem mass tag (TMT)-labeled quantitative proteomic analysis of plasma and plasma exosome samples from healthy individuals and patients with PD using liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total of 724 proteins were quantified in the plasma samples, and 611 proteins were screened from the exosome samples. Among these 611 proteins, 413 were found in the Exosomal Protein Database (Exocarta). Using |log<sub>2</sub>FC|>0.26 and <i>P</i>-value (<i>P</i>)<0.05 as the cutoff, five upregulated and six downregulated proteins were identified in the plasma samples of the PD group compared with the healthy group. In the plasma exosome samples, compared with the healthy group, the PD group showed six upregulated and seven downregulated proteins. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted based on gene set enrichment analysis (GSEA). GO-cellular component (CC) analysis revealed that plasma-enriched proteins were mainly located in the nucleus whereas plasma exosome-enriched proteins were mainly located in the cytoplasm. According to the GO-molecular function (MF) analysis, the MFs of differentially expressed proteins in the plasma were mainly enriched in RNA, D","PeriodicalId":9864,"journal":{"name":"色谱","volume":"41 12","pages":"1073-1083"},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10719805/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138797670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-01DOI: 10.3724/SP.J.1123.2023.07017
Xianli Wang, Qinxiong Rao, Qicai Zhang, Penghui DU, Weiguo Song
<p><p>Perfluoroalkyl substances (PFASs) have become a new food-safety problem. Dietary intake is a major pathway of human exposure to PFASs. Chinese mitten crab (<i>Eriocheir sinensis</i>) is a high-end aquaculture product popular among consumers in China. Conventional extraction methods for PFASs are cumbersome and time consuming, and result in incomplete purification; thus, this technique does not meet the requirements for PFAS detection. Herein, an analytical strategy was established for the rapid detection of 14 PFASs in Chinese mitten crab based on multi-plug filtration cleanup (m-PFC) and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The carbon-chain length of the 14 PFASs analyzed in this study ranged from 4 to 14, and they are perfluorobutanoic acid (PFBA), perfluoro-<i>n</i>-pentanoic acid (PFPeA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA), perfluorotetradecanoic acid (PFTeDA), perfluoro-1-butane sulfonic acid (PFBS), perfluoro-1-hexane sulfonic acid (PFHxS), perfluoro-1-octane sulfonic acid (PFOS), and perfluoro-1-decanesulfonate (PFDS). The m-PFC column was prepared using carboxy-based multiwalled carbon nanotubes, and used to reduce the interference of sample impurities. The samples were extracted with 5 mL of 0.1% formic acid aqueous solution, 15 mL of acetonitrile and extraction salt (2 g Na<sub>2</sub>SO<sub>4</sub> and 2 g NaCl). The supernatant (10 mL) was purified using the m-PFC column, concentrated to near dryness under nitrogen, and then redissolved in 1 mL of methanol. Finally, the sample solution was filtered through a 0.22 μm polypropylene syringe filter for UPLC-MS/MS analysis. The target analytes were separated using a Shimadzu Shim-pack G1ST-C18 chromatographic column (100 mm×2.1 mm, 2 μm) using methanol (A) and 5 mmol/L ammonium acetate aqueous solution (B) as the mobile phases via gradient elution. The linear gradient program were as follows: 0-0.5 min, 10%A-35%A; 0.5-3 min, 35%A-60%A; 3-5 min, 60%A-100%A; 5-6.5 min, 100%A; 6.5-7 min, 100%A-10%A. The target analytes were analyzed using negative electrospray ionization in multiple-reaction monitoring mode, and quantitative analysis was performed using the internal standard method. In this study, we optimized the mobile-phase system as well as the extraction solvent, time, volume, and salt. The 14 PFASs exhibited good peak shapes and sensitivities when the 5 mmol/L ammonium acetate solution-methanol system was used as the mobile phase. Compared with acetonitrile or methanol alone, the extraction efficiencies of the 14 PFASs were significantly improved when 5 mL of 0.1% formic acid aqueous solution was added, followed by 15 mL of acetonitrile. The extraction efficiencies of the 14 PFASs did not differ significantly when the extraction time was within 3-15 m
{"title":"[Determination of 14 perfluoroalkyl substances in Chinese mitten crab by multi-plug filtration cleanup coupled with ultra-performance liquid chromatography-tandem mass spectrometry].","authors":"Xianli Wang, Qinxiong Rao, Qicai Zhang, Penghui DU, Weiguo Song","doi":"10.3724/SP.J.1123.2023.07017","DOIUrl":"https://doi.org/10.3724/SP.J.1123.2023.07017","url":null,"abstract":"<p><p>Perfluoroalkyl substances (PFASs) have become a new food-safety problem. Dietary intake is a major pathway of human exposure to PFASs. Chinese mitten crab (<i>Eriocheir sinensis</i>) is a high-end aquaculture product popular among consumers in China. Conventional extraction methods for PFASs are cumbersome and time consuming, and result in incomplete purification; thus, this technique does not meet the requirements for PFAS detection. Herein, an analytical strategy was established for the rapid detection of 14 PFASs in Chinese mitten crab based on multi-plug filtration cleanup (m-PFC) and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The carbon-chain length of the 14 PFASs analyzed in this study ranged from 4 to 14, and they are perfluorobutanoic acid (PFBA), perfluoro-<i>n</i>-pentanoic acid (PFPeA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA), perfluorotetradecanoic acid (PFTeDA), perfluoro-1-butane sulfonic acid (PFBS), perfluoro-1-hexane sulfonic acid (PFHxS), perfluoro-1-octane sulfonic acid (PFOS), and perfluoro-1-decanesulfonate (PFDS). The m-PFC column was prepared using carboxy-based multiwalled carbon nanotubes, and used to reduce the interference of sample impurities. The samples were extracted with 5 mL of 0.1% formic acid aqueous solution, 15 mL of acetonitrile and extraction salt (2 g Na<sub>2</sub>SO<sub>4</sub> and 2 g NaCl). The supernatant (10 mL) was purified using the m-PFC column, concentrated to near dryness under nitrogen, and then redissolved in 1 mL of methanol. Finally, the sample solution was filtered through a 0.22 μm polypropylene syringe filter for UPLC-MS/MS analysis. The target analytes were separated using a Shimadzu Shim-pack G1ST-C18 chromatographic column (100 mm×2.1 mm, 2 μm) using methanol (A) and 5 mmol/L ammonium acetate aqueous solution (B) as the mobile phases via gradient elution. The linear gradient program were as follows: 0-0.5 min, 10%A-35%A; 0.5-3 min, 35%A-60%A; 3-5 min, 60%A-100%A; 5-6.5 min, 100%A; 6.5-7 min, 100%A-10%A. The target analytes were analyzed using negative electrospray ionization in multiple-reaction monitoring mode, and quantitative analysis was performed using the internal standard method. In this study, we optimized the mobile-phase system as well as the extraction solvent, time, volume, and salt. The 14 PFASs exhibited good peak shapes and sensitivities when the 5 mmol/L ammonium acetate solution-methanol system was used as the mobile phase. Compared with acetonitrile or methanol alone, the extraction efficiencies of the 14 PFASs were significantly improved when 5 mL of 0.1% formic acid aqueous solution was added, followed by 15 mL of acetonitrile. The extraction efficiencies of the 14 PFASs did not differ significantly when the extraction time was within 3-15 m","PeriodicalId":9864,"journal":{"name":"色谱","volume":"41 12","pages":"1095-1105"},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10719808/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138797575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
<p><p>Glucocorticoids, which are a class of steroidal hormones secreted by the adrenal cortex, have significant anti-inflammatory, immunosuppressive, and anti-allergic effects. Thus, these compounds are widely used in clinical practice. However, the long-term use of cosmetics containing glucocorticoids can lead to serious consequences, such as hormone-dependent dermatitis, hypertension, and other serious injuries. The Safety and Technical Specification for Cosmetics (2015 edition) and Regulation (EC) No. 1223/2009 of the European Parliament and Council on cosmetic products list glucocorticoids as prohibited raw materials. According to the National Medical Products Administration, reports on the illegal addition of glucocorticoids to cosmetics by manufacturers have increased in recent years. Therefore, establishing high-throughput screening methods to ensure the quality and safety of cosmetics is imperative. In this study, a comprehensive analytical method based on ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the rapid screening of 83 glucocorticoids in cosmetics. A series of conditions were optimized using three matrices that are commonly used in cosmetics: water, lotion, and cream (o/w-type). Four mobile-phase systems and three chromatographic columns were then optimized to achieve the best separation effects. Various MS parameters, such as the capillary voltages, cone voltages, desolvation gas flow rates, and collision energies of the ion pairs of the target compounds, were also optimized. Furthermore, pretreatment was essential for glucocorticoid determination owing to the complex matrix effects of cosmetics. The analytes were divided into two groups, with lg <i>K</i><sub>ow</sub>=4 as the limit, to compare the effects of the extraction solvent on recoveries. The extraction recoveries of target analytes with six extraction methods, namely, extraction with acetonitrile, extraction with acetone, extraction with ethyl acetate, dispersion in saturated sodium chloride solution followed by extraction with acetonitrile, dispersion in saturated sodium chloride solution followed by extraction with acetone, and dispersion in saturated sodium chloride solution followed by extraction with ethyl acetate, were compared. The recoveries from QuEChERS and solid-phase extraction (SPE) purification were also compared. Based on the experimental results, the final sample pretreatment method included acetonitrile vortex dispersion, ultrasonic extraction, and sample loading after filtration. The 83 target compounds were separated on a Thermo Accucore PFP column (100 mm×2.1 mm, 2.6 μm) with 0.1% (v/v) acetic acid in acetonitrile and 0.1% (v/v) acetic acid in water as the mobile phases. The analytes were determined by dynamic multiple-reaction monitoring (MRM) in electrospray positive ionization mode (ESI<sup>+</sup>) and quantified using the external standard method. Matrix standard curves were used to reduce matrix
{"title":"[Simultaneous determination of 83 glucocorticoids in cosmetics by ultra performance liquid chromatography-tandem mass spectrometry].","authors":"Qianru Zhao, Hua Liu, Yaping Meng, Xiang Li, Ruifang Gao, Xiangsheng Li","doi":"10.3724/SP.J.1123.2023.04009","DOIUrl":"https://doi.org/10.3724/SP.J.1123.2023.04009","url":null,"abstract":"<p><p>Glucocorticoids, which are a class of steroidal hormones secreted by the adrenal cortex, have significant anti-inflammatory, immunosuppressive, and anti-allergic effects. Thus, these compounds are widely used in clinical practice. However, the long-term use of cosmetics containing glucocorticoids can lead to serious consequences, such as hormone-dependent dermatitis, hypertension, and other serious injuries. The Safety and Technical Specification for Cosmetics (2015 edition) and Regulation (EC) No. 1223/2009 of the European Parliament and Council on cosmetic products list glucocorticoids as prohibited raw materials. According to the National Medical Products Administration, reports on the illegal addition of glucocorticoids to cosmetics by manufacturers have increased in recent years. Therefore, establishing high-throughput screening methods to ensure the quality and safety of cosmetics is imperative. In this study, a comprehensive analytical method based on ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the rapid screening of 83 glucocorticoids in cosmetics. A series of conditions were optimized using three matrices that are commonly used in cosmetics: water, lotion, and cream (o/w-type). Four mobile-phase systems and three chromatographic columns were then optimized to achieve the best separation effects. Various MS parameters, such as the capillary voltages, cone voltages, desolvation gas flow rates, and collision energies of the ion pairs of the target compounds, were also optimized. Furthermore, pretreatment was essential for glucocorticoid determination owing to the complex matrix effects of cosmetics. The analytes were divided into two groups, with lg <i>K</i><sub>ow</sub>=4 as the limit, to compare the effects of the extraction solvent on recoveries. The extraction recoveries of target analytes with six extraction methods, namely, extraction with acetonitrile, extraction with acetone, extraction with ethyl acetate, dispersion in saturated sodium chloride solution followed by extraction with acetonitrile, dispersion in saturated sodium chloride solution followed by extraction with acetone, and dispersion in saturated sodium chloride solution followed by extraction with ethyl acetate, were compared. The recoveries from QuEChERS and solid-phase extraction (SPE) purification were also compared. Based on the experimental results, the final sample pretreatment method included acetonitrile vortex dispersion, ultrasonic extraction, and sample loading after filtration. The 83 target compounds were separated on a Thermo Accucore PFP column (100 mm×2.1 mm, 2.6 μm) with 0.1% (v/v) acetic acid in acetonitrile and 0.1% (v/v) acetic acid in water as the mobile phases. The analytes were determined by dynamic multiple-reaction monitoring (MRM) in electrospray positive ionization mode (ESI<sup>+</sup>) and quantified using the external standard method. Matrix standard curves were used to reduce matrix ","PeriodicalId":9864,"journal":{"name":"色谱","volume":"41 12","pages":"1084-1094"},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10719809/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138797665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-01DOI: 10.3724/SP.J.1123.2023.07003
Tao Yu, Li Chen, Wenmin Zhang, Lan Zhang, Qiaomei Lu
Sample pretreatment is an essential step in chromatographic analysis. Solid phase extraction (SPE) is a widely used sample pretreatment method. In SPE, the quality of the adsorbent directly affects the adsorption and enrichment efficiency of the target compounds as well as the sensitivity and selectivity of the pretreatment and subsequent analysis. Therefore, the selection and development of adsorbents has become a research hotspot. Microporous organic networks (MONs) are a novel type of covalent organic materials that are synthesized by the Sonogashira reaction of aromatic alkynes and aromatic halides. These networks have the advantages of modifiable structures, large specific surface areas, high porosity, and simple synthesis methods. This paper reviews the synthesis and functional modification methods of MONs, with an emphasis on their applications in sample pretreatment. Future development trends are also prospected. In terms of synthesis, the preparation methods for MON-based materials have progressed from reflux and solvothermal synthesis to room-temperature synthesis, the conditions of which tend to be milder and more efficient. In terms of functional modification, the introduction of macromolecules and active groups (including amino, hydroxyl, and carboxylic groups) can increase the selectivity and active sites of MON-based materials. The combination of MONs with Fe3O4, SiO2, and metal organic frameworks yields core-shell-structured MONs. Furtherly, they can be calcined and etched to form porous carbon structures or hollow multilayer materials. Functionalized MONs and their composite materials have multiple interaction mechanisms (e. g., hydrogen bonding, hydrophobic, electrostatic, and π-π interactions) with various target compounds, thereby realizing their efficient extraction. MONs can be used as adsorbent materials in SPE, Solid phase microextraction, dispersed solid phase extraction, magnetic solid phase extraction, and other pretreatment methods. When combined with chromatography and chromatography-mass spectrometry, MONs achieve good adsorption effects and high sensitivity, demonstrating the application potential of these materials in sample pretreatment.
样品预处理是色谱分析的重要步骤。固相萃取(SPE)是一种广泛使用的样品前处理方法。在 SPE 中,吸附剂的质量直接影响目标化合物的吸附和富集效率,以及预处理和后续分析的灵敏度和选择性。因此,吸附剂的选择和开发已成为研究热点。微孔有机网络(MONs)是一种新型共价有机材料,由芳香族炔烃和芳香族卤化物通过 Sonogashira 反应合成。这些网络具有结构可调、比表面积大、孔隙率高和合成方法简单等优点。本文综述了 MONs 的合成和功能修饰方法,重点介绍了它们在样品预处理中的应用。同时还展望了未来的发展趋势。在合成方面,MON 基材料的制备方法已从回流和溶热合成发展到室温合成,其条件趋于温和,效率更高。在功能修饰方面,引入大分子和活性基团(包括氨基、羟基和羧基)可以提高 MON 基材料的选择性和活性位点。将 MONs 与 Fe3O4、SiO2 和金属有机框架结合,可得到核壳结构的 MONs。此外,它们还可以通过煅烧和蚀刻形成多孔碳结构或中空多层材料。功能化 MONs 及其复合材料与各种目标化合物具有多种相互作用机制(如氢键、疏水、静电和 π-π 相互作用),从而实现了对目标化合物的高效萃取。MONs 可作为吸附材料用于 SPE、固相微萃取、分散固相萃取、磁性固相萃取和其他预处理方法。当与色谱法和色谱-质谱法结合使用时,MONs 可达到良好的吸附效果和较高的灵敏度,显示了这些材料在样品前处理中的应用潜力。
{"title":"[Advances in synthesis methods and applications of microporous organic networks for sample preparation].","authors":"Tao Yu, Li Chen, Wenmin Zhang, Lan Zhang, Qiaomei Lu","doi":"10.3724/SP.J.1123.2023.07003","DOIUrl":"https://doi.org/10.3724/SP.J.1123.2023.07003","url":null,"abstract":"<p><p>Sample pretreatment is an essential step in chromatographic analysis. Solid phase extraction (SPE) is a widely used sample pretreatment method. In SPE, the quality of the adsorbent directly affects the adsorption and enrichment efficiency of the target compounds as well as the sensitivity and selectivity of the pretreatment and subsequent analysis. Therefore, the selection and development of adsorbents has become a research hotspot. Microporous organic networks (MONs) are a novel type of covalent organic materials that are synthesized by the Sonogashira reaction of aromatic alkynes and aromatic halides. These networks have the advantages of modifiable structures, large specific surface areas, high porosity, and simple synthesis methods. This paper reviews the synthesis and functional modification methods of MONs, with an emphasis on their applications in sample pretreatment. Future development trends are also prospected. In terms of synthesis, the preparation methods for MON-based materials have progressed from reflux and solvothermal synthesis to room-temperature synthesis, the conditions of which tend to be milder and more efficient. In terms of functional modification, the introduction of macromolecules and active groups (including amino, hydroxyl, and carboxylic groups) can increase the selectivity and active sites of MON-based materials. The combination of MONs with Fe<sub>3</sub>O<sub>4</sub>, SiO<sub>2</sub>, and metal organic frameworks yields core-shell-structured MONs. Furtherly, they can be calcined and etched to form porous carbon structures or hollow multilayer materials. Functionalized MONs and their composite materials have multiple interaction mechanisms (e. g., hydrogen bonding, hydrophobic, electrostatic, and <i>π-π</i> interactions) with various target compounds, thereby realizing their efficient extraction. MONs can be used as adsorbent materials in SPE, Solid phase microextraction, dispersed solid phase extraction, magnetic solid phase extraction, and other pretreatment methods. When combined with chromatography and chromatography-mass spectrometry, MONs achieve good adsorption effects and high sensitivity, demonstrating the application potential of these materials in sample pretreatment.</p>","PeriodicalId":9864,"journal":{"name":"色谱","volume":"41 12","pages":"1052-1061"},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10719803/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138797543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-01DOI: 10.3724/SP.J.1123.2023.04026
Hongwen Zhai, Hongyu Ma, Meirong Cao, Mingxing Zhang, Junmei Ma, Yan Zhang, Qiang Li
<p><p>Food safety has received increased attention, and food detection is of great significance. The food matrix is complex, and diverse food hazards have been identified. Thus, the detection methods and sample preparation techniques for food matrices must be continuously optimized and updated. Several steps are usually required when a chromatographic system is used to determine food hazards: sample preparation, that is, the separation of targets from different substrates using a suitable preprocessing method and target-substance separation and purification, which is usually achieved using chromatographic separation. The selection of an appropriate detector for qualitative and quantitative analyses is usually based on the properties of the target compound. The sample preparation procedure is considered the most time-consuming aspect of the entire food-analysis process. It is also prone to analytical errors. Therefore, optimization of the sample preparation process is a key issue in the field of chemical analysis. Researchers have developed a series of new, efficient, and accurate sample preprocessing methods, and an on-line sample-preparation system has been found to be a feasible approach. On-line sample preparation coupled with liquid chromatography-mass spectrometry (LC-MS) presents many advantages. First, manual operation could reduce analytical errors to ensure good accuracy and repeatability. It could also reduce the consumption of chemical reagents and avoid cross-contamination between samples. Furthermore, an on-line sample-preparation system could shorten the sample-preparation time and improve the detection efficiency. On-line sample preparation coupled with LC-MS has been widely applied in the fields of environment, biology, and food. On-line sample preparation systems coupled with LC-MS are divided into two modules: the first modules involves sample preparation and the second module involves the LC system. The first module remove impurities and isolates the target compounds in preparation for their qualitative and quantitative detection. The coupling of these two modules depends mainly on valve switching. In this paper, we introduce the most frequently used on-line sample-preparation techniques, including on-line solid phase extraction (on-line SPE), in-tube solid phase microextraction (in-tube SPME), and turbulent chromatography (TFC). We then describe the basic principles and coupling equipment of these three on-line analytical technologies in detail. The coupling equipment establishes a physical connection between the two modules. Next, we discuss the properties of different purification fillers in an on-line sample-preparation column. The applications and research progress of on-line systems for pesticide residues, veterinary drug residues, and biotoxins are also discussed. Compared with offline sample preparation, on-line analytical systems present several advantages. On-line analytical systems can not only greatly reduce the ana
食品安全日益受到人们的关注,食品检测意义重大。食品基质复杂,食品危害多样。因此,食品基质的检测方法和样品制备技术必须不断优化和更新。使用色谱系统检测食品危害通常需要几个步骤:样品制备,即使用合适的预处理方法从不同基质中分离目标物;目标物分离和纯化,通常使用色谱分离来实现。通常根据目标化合物的特性选择合适的检测器进行定性和定量分析。样品制备过程被认为是整个食品分析过程中最耗时的环节。它还容易造成分析误差。因此,优化样品制备过程是化学分析领域的一个关键问题。研究人员已经开发出一系列新型、高效、准确的样品预处理方法,并发现在线样品制备系统是一种可行的方法。在线样品制备与液相色谱-质谱联用(LC-MS)具有许多优点。首先,人工操作可减少分析误差,确保良好的准确性和重复性。它还可以减少化学试剂的消耗,避免样品之间的交叉污染。此外,在线样品制备系统可以缩短样品制备时间,提高检测效率。与 LC-MS 相结合的在线样品制备系统已广泛应用于环境、生物和食品等领域。与液相色谱-质谱联用的在线样品制备系统分为两个模块:第一模块涉及样品制备,第二模块涉及液相色谱系统。第一个模块去除杂质,分离目标化合物,为定性和定量检测做准备。这两个模块的耦合主要取决于阀门的开关。本文将介绍最常用的在线样品制备技术,包括在线固相萃取(on-line SPE)、管内固相微萃取(in-tube SPME)和湍流色谱(TFC)。然后,我们将详细介绍这三种在线分析技术的基本原理和耦合设备。耦合设备在两个模块之间建立物理连接。接下来,我们讨论了在线样品制备柱中不同纯化填料的特性。此外,还讨论了在线系统在农药残留、兽药残留和生物毒素方面的应用和研究进展。与离线样品制备相比,在线分析系统具有多种优势。在线分析系统不仅能大大减少分析时间和溶剂消耗,还能提高检测灵敏度和准确度。此类系统可用于确定食品危害,确保食品安全。最后,对在线分析系统存在的问题和发展趋势进行了讨论和展望。为促进在线分析技术在食品安全检测中的应用,我们建议从以下三个方面着手。首先,除 C18 或聚合物填料外,应开发更多使用新型填料的在线纯化柱。其次,与普通检测器相比,高分辨率 MS 检测器具有更高的精度和准确度。将在线分析技术与高分辨率质谱仪结合起来可能有利于在线分析的进一步发展。第三,应对不同的食品基质进行比较和评估,不断优化检测过程,提高在线分析系统的效率。随着人们对食品安全问题的日益关注,在线分析技术在食品检测方面的应用将变得越来越重要。
{"title":"[Application progress of on-line sample preparation techniques coupled with liquid chromatography-mass spectrometry system in the detection of food hazards].","authors":"Hongwen Zhai, Hongyu Ma, Meirong Cao, Mingxing Zhang, Junmei Ma, Yan Zhang, Qiang Li","doi":"10.3724/SP.J.1123.2023.04026","DOIUrl":"https://doi.org/10.3724/SP.J.1123.2023.04026","url":null,"abstract":"<p><p>Food safety has received increased attention, and food detection is of great significance. The food matrix is complex, and diverse food hazards have been identified. Thus, the detection methods and sample preparation techniques for food matrices must be continuously optimized and updated. Several steps are usually required when a chromatographic system is used to determine food hazards: sample preparation, that is, the separation of targets from different substrates using a suitable preprocessing method and target-substance separation and purification, which is usually achieved using chromatographic separation. The selection of an appropriate detector for qualitative and quantitative analyses is usually based on the properties of the target compound. The sample preparation procedure is considered the most time-consuming aspect of the entire food-analysis process. It is also prone to analytical errors. Therefore, optimization of the sample preparation process is a key issue in the field of chemical analysis. Researchers have developed a series of new, efficient, and accurate sample preprocessing methods, and an on-line sample-preparation system has been found to be a feasible approach. On-line sample preparation coupled with liquid chromatography-mass spectrometry (LC-MS) presents many advantages. First, manual operation could reduce analytical errors to ensure good accuracy and repeatability. It could also reduce the consumption of chemical reagents and avoid cross-contamination between samples. Furthermore, an on-line sample-preparation system could shorten the sample-preparation time and improve the detection efficiency. On-line sample preparation coupled with LC-MS has been widely applied in the fields of environment, biology, and food. On-line sample preparation systems coupled with LC-MS are divided into two modules: the first modules involves sample preparation and the second module involves the LC system. The first module remove impurities and isolates the target compounds in preparation for their qualitative and quantitative detection. The coupling of these two modules depends mainly on valve switching. In this paper, we introduce the most frequently used on-line sample-preparation techniques, including on-line solid phase extraction (on-line SPE), in-tube solid phase microextraction (in-tube SPME), and turbulent chromatography (TFC). We then describe the basic principles and coupling equipment of these three on-line analytical technologies in detail. The coupling equipment establishes a physical connection between the two modules. Next, we discuss the properties of different purification fillers in an on-line sample-preparation column. The applications and research progress of on-line systems for pesticide residues, veterinary drug residues, and biotoxins are also discussed. Compared with offline sample preparation, on-line analytical systems present several advantages. On-line analytical systems can not only greatly reduce the ana","PeriodicalId":9864,"journal":{"name":"色谱","volume":"41 12","pages":"1062-1072"},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10719810/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138797559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
<p><p>Boron and silicon are widely distributed in nature; in water, these compounds typically present in the forms of boric acid and silicic acid, respectively. The maximum allowable levels of silicic acid and boric acid in water are stipulated in relevant national and industry standards, such as GB 8538-2022. Quality changes in water, which are of great significance in water-quality evaluations, can be understood in terms of its silicic acid and boric acid contents. Boric acid content is usually determined by ion exclusion chromatography, whereas silicic acid content is usually determined by postcolumn derivatization. Therefore, traditional methods cannot achieve the simultaneous determination of silicic acid and boric acid contents in water. Modern ion chromatography has been widely used in the detection of ionic compounds, such as anions, cations, organic acids, organic amines, amino acids, and sugars. Boric (p<i>K</i><sub>a</sub>=9.24) and silicic (p<i>K</i><sub>a</sub>=9.77) acids are weak acids that dissociate into ionic states under alkaline conditions. Although these compounds cannot be tested using suppressed ion chromatography, they can be retained on ion chromatography columns. In this study, a method based on nonsuppressed conductance detection was established for the simultaneous determination of boric acid and silicic acid in water. The contents of boric acid and silicic acid were detected by nonsuppressed ion chromatography using a Dionex IonPac<sup>TM</sup> AS20 analytical column. The chromatographic conditions were as follows: flow rate, 1.0 mL/min; column temperature, 30 ℃; eluent, 6 mmol/L sodium hydroxide solution and 60 mmol/L mannitol; and sample injection volume, 50 μL. The effective separation of silicic acid and boric acid was achieved within 8 min. SiO<sub>3</sub><sup>2-</sup> and boric acid demonstrated good linear relationships in the concentration ranges of 0.25-100 and 0.5-100 mg/L (correlation coefficients, 0.9999), respectively. The method detection (MDL) and quantification (MQL) limits were 0.078 and 0.26 mg/L for SiO<sub>3</sub><sup>2-</sup>, and the MDL and MQL limits were 0.18 and 0.60 mg/L for boric acid. The average recoveries of boric acid and SiO<sub>3</sub><sup>2-</sup> (<i>n</i>=6) were 97.3%-105.3%. Moreover, the relative standard deviations were less than 0.9% for boric acid at four spiked levels and less than 0.30% for SiO<sub>3</sub><sup>2-</sup> at three spiked levels. Thus, the method meets detection requirements. The pretreatment method is very simple, and the sample can be directly injected through a 0.22 μm water filtration membrane and into the column. The boric acid and silicic acid contents in nine mineral drinking water samples were determined under the optimized analytical conditions. Boric acid was not detected in these nine samples, but silicic acid was detected in six samples. The silicic acid contents detected were between 18.70 and 62.08 mg/L, which was consistent with the concentration
{"title":"[Determination of boric acid and silicic acid in mineral water by nonsuppressed ion chromatography].","authors":"Zhanqiang Yang, Fangfang Zhang, Chunxia Han, Hongguo Zheng","doi":"10.3724/SP.J.1123.2023.09025","DOIUrl":"https://doi.org/10.3724/SP.J.1123.2023.09025","url":null,"abstract":"<p><p>Boron and silicon are widely distributed in nature; in water, these compounds typically present in the forms of boric acid and silicic acid, respectively. The maximum allowable levels of silicic acid and boric acid in water are stipulated in relevant national and industry standards, such as GB 8538-2022. Quality changes in water, which are of great significance in water-quality evaluations, can be understood in terms of its silicic acid and boric acid contents. Boric acid content is usually determined by ion exclusion chromatography, whereas silicic acid content is usually determined by postcolumn derivatization. Therefore, traditional methods cannot achieve the simultaneous determination of silicic acid and boric acid contents in water. Modern ion chromatography has been widely used in the detection of ionic compounds, such as anions, cations, organic acids, organic amines, amino acids, and sugars. Boric (p<i>K</i><sub>a</sub>=9.24) and silicic (p<i>K</i><sub>a</sub>=9.77) acids are weak acids that dissociate into ionic states under alkaline conditions. Although these compounds cannot be tested using suppressed ion chromatography, they can be retained on ion chromatography columns. In this study, a method based on nonsuppressed conductance detection was established for the simultaneous determination of boric acid and silicic acid in water. The contents of boric acid and silicic acid were detected by nonsuppressed ion chromatography using a Dionex IonPac<sup>TM</sup> AS20 analytical column. The chromatographic conditions were as follows: flow rate, 1.0 mL/min; column temperature, 30 ℃; eluent, 6 mmol/L sodium hydroxide solution and 60 mmol/L mannitol; and sample injection volume, 50 μL. The effective separation of silicic acid and boric acid was achieved within 8 min. SiO<sub>3</sub><sup>2-</sup> and boric acid demonstrated good linear relationships in the concentration ranges of 0.25-100 and 0.5-100 mg/L (correlation coefficients, 0.9999), respectively. The method detection (MDL) and quantification (MQL) limits were 0.078 and 0.26 mg/L for SiO<sub>3</sub><sup>2-</sup>, and the MDL and MQL limits were 0.18 and 0.60 mg/L for boric acid. The average recoveries of boric acid and SiO<sub>3</sub><sup>2-</sup> (<i>n</i>=6) were 97.3%-105.3%. Moreover, the relative standard deviations were less than 0.9% for boric acid at four spiked levels and less than 0.30% for SiO<sub>3</sub><sup>2-</sup> at three spiked levels. Thus, the method meets detection requirements. The pretreatment method is very simple, and the sample can be directly injected through a 0.22 μm water filtration membrane and into the column. The boric acid and silicic acid contents in nine mineral drinking water samples were determined under the optimized analytical conditions. Boric acid was not detected in these nine samples, but silicic acid was detected in six samples. The silicic acid contents detected were between 18.70 and 62.08 mg/L, which was consistent with the concentration","PeriodicalId":9864,"journal":{"name":"色谱","volume":"41 12","pages":"1121-1126"},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10719811/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138797590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-01DOI: 10.3724/SP.J.1123.2023.09028
Dongmei Guo, Yiran Xia, Ur Rahman Mujeeb, Jianzhong Wang, Jiawei Liu, Quan Bai
Antibodies play an essential role in cancer diagnosis and treatment because of the specificity for target biomolecules and reduction of side effects. However, antibodies separation and purification still face some challenges. Antibody elution from columns using a low-pH aqueous solution leads to aggregation or loss of activity of the antibody drugs. In this paper, a block copolymer-based temperature-responsive affinity chromatography (TRAC) stationary phase, SiO2-P[NIPAM-b-4VP]-MEP using the block temperature-responsive copolymer poly(N-isopropylacrylamide-b-4-vinylpyridine) (P[NIPAM-b-4VP]) as the space arms and 4-mercaptoethyl pyridine (MEP) as the ligand was prepared for antibody separation. The TRAC column was tested using bovine serum albumin (BSA) and γ-globulin as model proteins, and the effects of salt concentration in the mobile phase and temperature on their separation were studied in detail. At 40 ℃, the TRAC stationary phase only selectively retained γ-globulin due to the specific affinity interaction between antibodies and the ligand MEP. At 5 ℃, γ-globulin can be eluted from the column with a mass recovery of 92.7% using a Tris-HCl buffer (pH 8.0) solution containing 0.6 mol/L NaCl. The adsorption capacity of γ-globulin on this stationary phase was (71.5 ±2.1) mg/g (n=3), which was twice that of a traditional temperature-sensitive affinity chromatography stationary phase SiO2-PNIPAM-MEP. The stationary phase was also used to separate and purify immunoglobulin (IgG) in human serum in one step by altering the temperature and ion strength of the mobile phase, resulting in a purity of 97.4%±0.7%. Thus, this new technology has specific selectivity for antibodies, as well as mild and green elution conditions, ultimately resolving the problem of traditional affinity chromatography using acid elution, which can lead to the antibodies aggregation/inactivation. This technology has great application potential for the industrial production of antibody drugs.
{"title":"[Preparation of a block copolymer-based temperature-responsive affinity chromatography stationary phase for antibody separation and purification].","authors":"Dongmei Guo, Yiran Xia, Ur Rahman Mujeeb, Jianzhong Wang, Jiawei Liu, Quan Bai","doi":"10.3724/SP.J.1123.2023.09028","DOIUrl":"https://doi.org/10.3724/SP.J.1123.2023.09028","url":null,"abstract":"<p><p>Antibodies play an essential role in cancer diagnosis and treatment because of the specificity for target biomolecules and reduction of side effects. However, antibodies separation and purification still face some challenges. Antibody elution from columns using a low-pH aqueous solution leads to aggregation or loss of activity of the antibody drugs. In this paper, a block copolymer-based temperature-responsive affinity chromatography (TRAC) stationary phase, SiO<sub>2</sub>-P[NIPAM-<i>b</i>-4VP]-MEP using the block temperature-responsive copolymer poly(<i>N</i>-isopropylacrylamide-<i>b</i>-4-vinylpyridine) (P[NIPAM-<i>b</i>-4VP]) as the space arms and 4-mercaptoethyl pyridine (MEP) as the ligand was prepared for antibody separation. The TRAC column was tested using bovine serum albumin (BSA) and <i>γ</i>-globulin as model proteins, and the effects of salt concentration in the mobile phase and temperature on their separation were studied in detail. At 40 ℃, the TRAC stationary phase only selectively retained <i>γ</i>-globulin due to the specific affinity interaction between antibodies and the ligand MEP. At 5 ℃, <i>γ</i>-globulin can be eluted from the column with a mass recovery of 92.7% using a Tris-HCl buffer (pH 8.0) solution containing 0.6 mol/L NaCl. The adsorption capacity of <i>γ</i>-globulin on this stationary phase was (71.5 ±2.1) mg/g (<i>n</i>=3), which was twice that of a traditional temperature-sensitive affinity chromatography stationary phase SiO<sub>2</sub>-PNIPAM-MEP. The stationary phase was also used to separate and purify immunoglobulin (IgG) in human serum in one step by altering the temperature and ion strength of the mobile phase, resulting in a purity of 97.4%±0.7%. Thus, this new technology has specific selectivity for antibodies, as well as mild and green elution conditions, ultimately resolving the problem of traditional affinity chromatography using acid elution, which can lead to the antibodies aggregation/inactivation. This technology has great application potential for the industrial production of antibody drugs.</p>","PeriodicalId":9864,"journal":{"name":"色谱","volume":"41 12","pages":"1045-1051"},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10719812/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138797641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}