Pub Date : 2024-10-28DOI: 10.1016/j.chroma.2024.465478
Ali Akbar Fathi , Mohammad Reza Afshar Mogaddam , Saeed Mohammad Sorouraddin , Mir Ali Farajzadeh
In this study, a new magnetic nanocomposite comprised of a molecularly imprinted polymer, metal organic framework, and covalent organic framework was synthesized and used in the dispersive solid-phase extraction of montelukast from plasma and urine samples. The extracted analyte was then analyzed using liquid chromatography-tandem mass spectrometry. The drug extraction process involved adding the synthesized nanocomposite to the biological sample. After vortexing, the solid particles were collected using an external magnet. The adsorbed analyte was subsequently eluted with acetonitrile. By combining of the developed method with liquid chromatography-tandem mass spectrometry, low limits of detection (0.04 and 0.05 ng mL−1 in urine and plasma, respectively) and quantification (0.14 and 0.16 ng mL−1 in urine and plasma, respectively), a wide linear range (0.14-300 and 0.16-300 ng mL−1 in urine and plasma, respectively), acceptable relative standard deviations for intra- and inter-day precisions (≤6.3 %), and good extraction recoveries (75 and 72 % in urine and plasma samples, respectively) were achieved.
本研究合成了一种由分子印迹聚合物、金属有机框架和共价有机框架组成的新型磁性纳米复合材料，并将其用于从血浆和尿液样品中分散固相萃取孟鲁司特。然后使用液相色谱-串联质谱法对提取的分析物进行分析。药物提取过程包括将合成的纳米复合材料添加到生物样品中。涡旋后，使用外部磁铁收集固体颗粒。吸附的分析物随后用乙腈洗脱。通过将所开发的方法与液相色谱-串联质谱相结合，该方法的检出限（尿液和血浆中分别为 0.04 和 0.05 ng mL-1）和定量限（尿液和血浆中分别为 0.14 和 0.16 ng mL-1）均较低，线性范围宽（0.尿液和血浆中分别为 0.14 和 0.16-300 ng mL-1）、可接受的日内和日间精确度相对标准偏差（≤6.3%）以及良好的提取回收率（尿液和血浆样品中分别为 75% 和 72%）。
{"title":"Synthesis of MIP@COF@MIL-156@Fe3O4 composite and its application in dispersive solid phase extraction of montelukast in plasma and urine samples","authors":"Ali Akbar Fathi , Mohammad Reza Afshar Mogaddam , Saeed Mohammad Sorouraddin , Mir Ali Farajzadeh","doi":"10.1016/j.chroma.2024.465478","DOIUrl":"10.1016/j.chroma.2024.465478","url":null,"abstract":"<div><div>In this study, a new magnetic nanocomposite comprised of a molecularly imprinted polymer, metal organic framework, and covalent organic framework was synthesized and used in the dispersive solid-phase extraction of montelukast from plasma and urine samples. The extracted analyte was then analyzed using liquid chromatography-tandem mass spectrometry. The drug extraction process involved adding the synthesized nanocomposite to the biological sample. After vortexing, the solid particles were collected using an external magnet. The adsorbed analyte was subsequently eluted with acetonitrile. By combining of the developed method with liquid chromatography-tandem mass spectrometry, low limits of detection (0.04 and 0.05 ng mL<sup>−1</sup> in urine and plasma, respectively) and quantification (0.14 and 0.16 ng mL<sup>−1</sup> in urine and plasma, respectively), a wide linear range (0.14-300 and 0.16-300 ng mL<sup>−1</sup> in urine and plasma, respectively), acceptable relative standard deviations for intra- and inter-day precisions (≤6.3 %), and good extraction recoveries (75 and 72 % in urine and plasma samples, respectively) were achieved.</div></div>","PeriodicalId":347,"journal":{"name":"Journal of Chromatography A","volume":"1738 ","pages":"Article 465478"},"PeriodicalIF":3.8,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142592740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-26DOI: 10.1016/j.chroma.2024.465473
Martina Lioi , Sara Tengattini , Valentina D'Atri , Gabriella Massolini , Simona Daly , Caterina Temporini , Davy Guillarme
This study presents a systematic approach for developing an innovative hydrophilic interaction liquid chromatography (HILIC) method for collagen peptide mapping analysis. The predominant post-translational modification (PTM) of collagen, proline hydroxylation, introduces polar hydroxyl groups throughout the collagen sequence, making HILIC a promising alternative to classical reversed-phase liquid chromatography (RPLC) approaches. This study employs sixteen model peptides, selected from in silico predicted tryptic peptides with zero missed cleavages and representing diverse physicochemical properties and structural motifs of collagen. The peptides were used as standards to conduct detailed chromatographic evaluation. Various HILIC stationary phases and mobile phases were systematically examined to identify optimal separation conditions for collagen peptides, contributing to a better understanding of peptide behavior in HILIC. The study also explores the effects of sample diluent and injection mode, comparing classical injection with the Performance Optimizing Injection Sequence (POISe), to determine their impact on HILIC performance. Introducing a plug of weak solvent (acetonitrile) prior to sample injection, effectively mitigates the mismatch in eluent strength between the fully aqueous sample diluent (resulting from tryptic digestion) and the mobile phase, addressing issues of peak distortion. Different injection volumes (from 0.5 to 8 µL) and acetonitrile ratios (1:1, 1:2, 1:5 and 1:10) were tested to optimize sample injection and increase sensitivity of collagen tryptic peptides.
Following method optimization, HILIC was coupled with mass spectrometry (MS) to evaluate its effectiveness in analyzing collagen-digested samples. This evaluation included the assessment of peptide sequence coverage and the method ability to identify hydroxylation patterns, thereby demonstrating its potential for detailed peptide analysis.
{"title":"Evaluating the potential of hydrophilic interaction liquid chromatography for collagen peptide mapping analysis","authors":"Martina Lioi , Sara Tengattini , Valentina D'Atri , Gabriella Massolini , Simona Daly , Caterina Temporini , Davy Guillarme","doi":"10.1016/j.chroma.2024.465473","DOIUrl":"10.1016/j.chroma.2024.465473","url":null,"abstract":"<div><div>This study presents a systematic approach for developing an innovative hydrophilic interaction liquid chromatography (HILIC) method for collagen peptide mapping analysis. The predominant post-translational modification (PTM) of collagen, proline hydroxylation, introduces polar hydroxyl groups throughout the collagen sequence, making HILIC a promising alternative to classical reversed-phase liquid chromatography (RPLC) approaches. This study employs sixteen model peptides, selected from <em>in silico</em> predicted tryptic peptides with zero missed cleavages and representing diverse physicochemical properties and structural motifs of collagen. The peptides were used as standards to conduct detailed chromatographic evaluation. Various HILIC stationary phases and mobile phases were systematically examined to identify optimal separation conditions for collagen peptides, contributing to a better understanding of peptide behavior in HILIC. The study also explores the effects of sample diluent and injection mode, comparing classical injection with the Performance Optimizing Injection Sequence (POISe), to determine their impact on HILIC performance. Introducing a plug of weak solvent (acetonitrile) prior to sample injection, effectively mitigates the mismatch in eluent strength between the fully aqueous sample diluent (resulting from tryptic digestion) and the mobile phase, addressing issues of peak distortion. Different injection volumes (from 0.5 to 8 µL) and acetonitrile ratios (1:1, 1:2, 1:5 and 1:10) were tested to optimize sample injection and increase sensitivity of collagen tryptic peptides.</div><div>Following method optimization, HILIC was coupled with mass spectrometry (MS) to evaluate its effectiveness in analyzing collagen-digested samples. This evaluation included the assessment of peptide sequence coverage and the method ability to identify hydroxylation patterns, thereby demonstrating its potential for detailed peptide analysis.</div></div>","PeriodicalId":347,"journal":{"name":"Journal of Chromatography A","volume":"1738 ","pages":"Article 465473"},"PeriodicalIF":3.8,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142586866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-26DOI: 10.1016/j.chroma.2024.465475
Pia Wittenhofer, Laura Kiesewetter, Oliver J. Schmitz, Sven W. Meckelmann
The biosynthesis and homeostasis of cholesterol are essential for cellular function. Cholesterol is a major lipid with multiple roles in membrane stability, signaling, or as a precursor for other molecules. Because of the structural similarity of the sterols involved in the biosynthesis, their accurate identification and quantification is still challenging. Moreover, the huge difference in the concentration of cholesterol and its precursors can cause interferences during the detection. To overcome these problems, a heart-cut liquid chromatographic method was developed by evaluating 38 different columns to achieve optimal separation. The method efficiently separates all sterol biosynthesis intermediates, with detection limits in the low nmol/L-range and an upper limit of quantification of 9 mmol/L for cholesterol by using triple quadrupole mass spectrometric detection. Investigation of lung carcinoma cells treated with statins demonstrated the capability to detect a biological response, showing inhibition of sterol synthesis. This technique offers a robust tool for studying cholesterol biosynthesis and its role in disease.
{"title":"Investigation of the Cholesterol Biosynthesis by Heart-Cut Liquid Chromatography and Mass Spectrometric Detection","authors":"Pia Wittenhofer, Laura Kiesewetter, Oliver J. Schmitz, Sven W. Meckelmann","doi":"10.1016/j.chroma.2024.465475","DOIUrl":"10.1016/j.chroma.2024.465475","url":null,"abstract":"<div><div>The biosynthesis and homeostasis of cholesterol are essential for cellular function. Cholesterol is a major lipid with multiple roles in membrane stability, signaling, or as a precursor for other molecules. Because of the structural similarity of the sterols involved in the biosynthesis, their accurate identification and quantification is still challenging. Moreover, the huge difference in the concentration of cholesterol and its precursors can cause interferences during the detection. To overcome these problems, a heart-cut liquid chromatographic method was developed by evaluating 38 different columns to achieve optimal separation. The method efficiently separates all sterol biosynthesis intermediates, with detection limits in the low nmol/L-range and an upper limit of quantification of 9 mmol/L for cholesterol by using triple quadrupole mass spectrometric detection. Investigation of lung carcinoma cells treated with statins demonstrated the capability to detect a biological response, showing inhibition of sterol synthesis. This technique offers a robust tool for studying cholesterol biosynthesis and its role in disease.</div></div>","PeriodicalId":347,"journal":{"name":"Journal of Chromatography A","volume":"1738 ","pages":"Article 465475"},"PeriodicalIF":3.8,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142567174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-25DOI: 10.1016/j.chroma.2024.465442
Carolina M. Bustamante , Natalia Bravo , Paula Ruiz , Joan O. Grimalt , Mercè Garí
{"title":"Corrigendum to “Method optimization for a simultaneous determination of neonicotinoid, carbamate/thiocarbamate, triazole, organophosphate and pyrethroid pesticides and their metabolites in urine using UPLC-MS/MS” [Journal of Chromatography A 1730 (2024) 465054]","authors":"Carolina M. Bustamante , Natalia Bravo , Paula Ruiz , Joan O. Grimalt , Mercè Garí","doi":"10.1016/j.chroma.2024.465442","DOIUrl":"10.1016/j.chroma.2024.465442","url":null,"abstract":"","PeriodicalId":347,"journal":{"name":"Journal of Chromatography A","volume":"1737 ","pages":"Article 465442"},"PeriodicalIF":3.8,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142492113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Proteins in wines contribute to “protein haze,” which, while not affecting health or taste, can detract from the visual appeal of wines to consumers. To mitigate this issue, winemakers commonly use fining agents such as bentonite, despite the high costs involved. To overcome these challenges, numerous studies employ various analytical methods to better understand the behaviour of proteins. A novel technique which separates compounds by size, Asymmetrical Flow-Field Flow Fractionation (AF4), allows for studying proteins without denaturing them. Given that most proteins share similar sizes, identification remains challenging. The aim of this work was initially to develop a new system enabling simultaneous analysis of the macromolecular profile of wines (proteins, mannoproteins) using AF4 and real-time protein nature analysis (hydrophobicity properties) using Ultra-High Performance Liquid Chromatography (UHPLC). By injecting two standards of different sizes and chemical nature, thaumatin protein and mannoproteins, the system was validated. The subsequent application of this system to Southwestern wines revealed distinct profiles across monovarietal white wines from four grape varieties. While the Colombard (COL) and Gros manseng (GM) varieties showed similar protein compositions with varying concentrations, the Len de l'el (LL) variety had only two types of protein and no protein was detected in the Mauzac (MZ) variety. Despite these variations, all varieties contained mannoproteins. This system shows promise for studying wine protein composition and could potentially find applications in other matrices.
{"title":"AF4-UHPLC: Two-dimensional separation of macromolecules in four white wines from South-Western France","authors":"Auriane Figué , Marianne Gosset , Frédéric Violleau","doi":"10.1016/j.chroma.2024.465456","DOIUrl":"10.1016/j.chroma.2024.465456","url":null,"abstract":"<div><div>Proteins in wines contribute to “protein haze,” which, while not affecting health or taste, can detract from the visual appeal of wines to consumers. To mitigate this issue, winemakers commonly use fining agents such as bentonite, despite the high costs involved. To overcome these challenges, numerous studies employ various analytical methods to better understand the behaviour of proteins. A novel technique which separates compounds by size, Asymmetrical Flow-Field Flow Fractionation (AF4), allows for studying proteins without denaturing them. Given that most proteins share similar sizes, identification remains challenging. The aim of this work was initially to develop a new system enabling simultaneous analysis of the macromolecular profile of wines (proteins, mannoproteins) using AF4 and real-time protein nature analysis (hydrophobicity properties) using Ultra-High Performance Liquid Chromatography (UHPLC). By injecting two standards of different sizes and chemical nature, thaumatin protein and mannoproteins, the system was validated. The subsequent application of this system to Southwestern wines revealed distinct profiles across monovarietal white wines from four grape varieties. While the Colombard (COL) and Gros manseng (GM) varieties showed similar protein compositions with varying concentrations, the Len de l'el (LL) variety had only two types of protein and no protein was detected in the Mauzac (MZ) variety. Despite these variations, all varieties contained mannoproteins. This system shows promise for studying wine protein composition and could potentially find applications in other matrices.</div></div>","PeriodicalId":347,"journal":{"name":"Journal of Chromatography A","volume":"1738 ","pages":"Article 465456"},"PeriodicalIF":3.8,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142563824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-24DOI: 10.1016/j.chroma.2024.465462
Xiao-Hua Zhang , Shi-Yu Li , Jing-Jing Zheng , Ming-Xuan Li , Hua-Zhe Wu , Kun Wen , Kewen Tang
At present, the matrix interference in traditional Chinese medicine (TCM) is still a great challenge for multi-residue pesticides analysis. Herein, an alcohol/salt aqueous two-phase system (ATPS) based on n-propanol and (NH4)2SO4 was developed by comparing the binodal curve phase diagrams and the extraction rates of pesticides. The specific extraction conditions, including the composition of the ATPS, temperature, pH, and extraction time were explored through single factor experiments, and subsequently optimized using orthogonal array design and response surface methodology. The optimal conditions for the (NH4)2SO4/n-propanol ATPS extraction were determined to be: extraction time of 30 min, (NH4)2SO4 concentration of 22 %, temperature of 62.07 °C, n-propanol concentration of 30.13 %, and pH value of 7.66. In addition, the HPLC-MS/MS quantitative analysis of 25 pesticides in TCMs (i.e., honeysuckle and lily) was accomplished with recovery rates ranging from 64.2 % to 117.1 %. Moreover, the greenness of this method was evaluated using an analytical greenness calculator, and compared with other extraction techniques. The results indicate that the developed method is simple, efficient, and environmentally friendly, capable of trace-level enriching and simultaneously detecting multi-residue pesticides in TCM.
{"title":"A green extraction method based on aqueous two-phase system for trace-level enrichment of multi-residue pesticides in traditional Chinese medicine prior to HPLC-MS/MS quantitative analysis","authors":"Xiao-Hua Zhang , Shi-Yu Li , Jing-Jing Zheng , Ming-Xuan Li , Hua-Zhe Wu , Kun Wen , Kewen Tang","doi":"10.1016/j.chroma.2024.465462","DOIUrl":"10.1016/j.chroma.2024.465462","url":null,"abstract":"<div><div>At present, the matrix interference in traditional Chinese medicine (TCM) is still a great challenge for multi-residue pesticides analysis. Herein, an alcohol/salt aqueous two-phase system (ATPS) based on <em>n</em>-propanol and (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub> was developed by comparing the binodal curve phase diagrams and the extraction rates of pesticides. The specific extraction conditions, including the composition of the ATPS, temperature, pH, and extraction time were explored through single factor experiments, and subsequently optimized using orthogonal array design and response surface methodology. The optimal conditions for the (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub>/<em>n</em>-propanol ATPS extraction were determined to be: extraction time of 30 min, (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub> concentration of 22 %, temperature of 62.07 °C, <em>n</em>-propanol concentration of 30.13 %, and pH value of 7.66. In addition, the HPLC-MS/MS quantitative analysis of 25 pesticides in TCMs (i.e., honeysuckle and lily) was accomplished with recovery rates ranging from 64.2 % to 117.1 %. Moreover, the greenness of this method was evaluated using an analytical greenness calculator, and compared with other extraction techniques. The results indicate that the developed method is simple, efficient, and environmentally friendly, capable of trace-level enriching and simultaneously detecting multi-residue pesticides in TCM.</div></div>","PeriodicalId":347,"journal":{"name":"Journal of Chromatography A","volume":"1738 ","pages":"Article 465462"},"PeriodicalIF":3.8,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142563821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-24DOI: 10.1016/j.chroma.2024.465471
James Disley, Mathieu Pierre Elie, Jose Gonzalez-Rodriguez
For several years, gas chromatography-mass spectrometry (GC–MS) has been used to identify gamma-hydroxybutyrate (GHB) in forensic toxicology cases. However, under injector port conditions GHB can dehydrate into gamma-butyrolactone (GBL). Therefore, it is important for GHB to undergo a derivatisation reaction before an analysis to avoid the production of GBL; various analytical methods have been developed for the analysis of GHB but very few methods use acylation as a form of derivatisation. This study explores the optimisation of injector port acylation of GHB to improve its detectability and thermostability. By utilising trifluoroacetic acid anhydride (TFAA) and heptafluorobutyric acid anhydride (HFBA) to enhance the chromatography and mass spectra of the resulting derivatives. As a result, both reagents improved the detectability of GHB, with TFAA producing more predominant peaks within the chromatogram and HFBA offering a more complex mass spectrum. The optimal injector temperature was found to be 240 °C for both reagents, which significantly increased the derivatisation yields. These results demonstrate the effectiveness of injector port acylation as an alternative derivatisation route for GHB related drug cases.
{"title":"Injector port acylation of γ-hydroxybutyrate (GHB): Condition optimisation, source adjustments, and characterisation of the derivatives","authors":"James Disley, Mathieu Pierre Elie, Jose Gonzalez-Rodriguez","doi":"10.1016/j.chroma.2024.465471","DOIUrl":"10.1016/j.chroma.2024.465471","url":null,"abstract":"<div><div>For several years, gas chromatography-mass spectrometry (GC–MS) has been used to identify gamma-hydroxybutyrate (GHB) in forensic toxicology cases. However, under injector port conditions GHB can dehydrate into gamma-butyrolactone (GBL). Therefore, it is important for GHB to undergo a derivatisation reaction before an analysis to avoid the production of GBL; various analytical methods have been developed for the analysis of GHB but very few methods use acylation as a form of derivatisation. This study explores the optimisation of injector port acylation of GHB to improve its detectability and thermostability. By utilising trifluoroacetic acid anhydride (TFAA) and heptafluorobutyric acid anhydride (HFBA) to enhance the chromatography and mass spectra of the resulting derivatives. As a result, both reagents improved the detectability of GHB, with TFAA producing more predominant peaks within the chromatogram and HFBA offering a more complex mass spectrum. The optimal injector temperature was found to be 240 °C for both reagents, which significantly increased the derivatisation yields. These results demonstrate the effectiveness of injector port acylation as an alternative derivatisation route for GHB related drug cases.</div></div>","PeriodicalId":347,"journal":{"name":"Journal of Chromatography A","volume":"1737 ","pages":"Article 465471"},"PeriodicalIF":3.8,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142542576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-22DOI: 10.1016/j.chroma.2024.465468
Ulrich Tallarek, Dzmitry Hlushkou, Andreas Steinhoff, Alexandra Höltzel
We performed multiscale simulations of analyte sorption and diffusion in hierarchical porosity models of monolithic silica columns for reversed-phase liquid chromatography to investigate how the mean mesopore size of the chromatographic bed and the analyte-specific interaction with the chromatographic interface influence the analyte diffusivity at various length scales. The reproduced experimental conditions comprised the retention of six analyte compounds of low to moderate solute polarity on a silica-based, endcapped, C18 stationary phase with water‒acetonitrile and water–methanol mobile phases whose elution strength was varied via the volumetric solvent ratio. Detailed information about the analyte-specific interfacial dynamics received from molecular dynamics simulations was incorporated through appropriate linker schemes into Brownian dynamics diffusion simulations in three hierarchical porosity models received from physical reconstructions of silica monoliths with a mean macropore size of 1.23 µm and mean mesopore sizes of 12.3, 21.3, or 25.7 nm. The mean mesopore size was found to have a similar influence on the effective mesopore diffusivity as the analyte polarity and the mobile-phase elution strength, which together determine the analyte residence time on a column. A smaller mesopore size attenuated the increase of the effective mesopore diffusivity with increasing mobile-phase elution strength significantly. The effective bed diffusivity was limited by the analyte residence time rather than by morphological details of the mesopore space. The stronger an analyte was retained by the chromatographic interface inside the mesopores, the slower became the mass transfer between the pore space hierarchies and the lower was the effective bed diffusivity. The B-terms of the plate height equation were finally generated with the bed diffusivities and phase-based retention factors derived from the hierarchical porosity models using additional information about the stationary-phase limit obtained from the analysis of analyte–bonded phase contacts. The B-terms highlight analyte- and mobile phase-specific behavior relevant to isocratic and gradient elution conditions in chromatographic practice. In particular, U-shaped B-term curves are observed due to the dominating contribution of the retention factor and the bed diffusivity to the B-term at low and high elution strength of the mobile phase, respectively.
我们对用于反相液相色谱的硅胶整体柱的分层孔隙度模型中的分析物吸附和扩散进行了多尺度模拟，以研究色谱床的平均中孔尺寸以及分析物与色谱界面的相互作用如何在不同长度尺度上影响分析物的扩散性。再现的实验条件包括在以二氧化硅为基质的端帽 C18 固定相上保留六种低至中等溶质极性的分析化合物，流动相为水-乙腈和水-甲醇，其洗脱强度通过体积溶剂比来改变。从分子动力学模拟中获得的有关特定分析物界面动力学的详细信息，通过适当的链接器方案被纳入布朗动力学扩散模拟中，这些模型来自平均大孔尺寸为 1.23 µm、平均中孔尺寸为 12.3、21.3 或 25.7 nm 的二氧化硅单片的物理重构。研究发现，平均中孔尺寸对有效中孔扩散率的影响与分析物极性和流动相洗脱强度相似，它们共同决定了分析物在色谱柱上的停留时间。中孔尺寸越小，有效中孔扩散率随流动相洗脱强度增加而增加的幅度就越大。有效床层扩散率受分析物停留时间的限制，而不是介孔空间形态细节的限制。中孔内的色谱界面对分析物的截留作用越强，孔隙空间层次之间的传质就越慢，有效床层扩散率就越低。通过分析分析物-结合相接触获得的静止相极限的附加信息，利用分层孔隙度模型得出的床层扩散率和基于相的保留因子，最终生成了板高方程的 B 项。B 项凸显了色谱实践中与等度和梯度洗脱条件相关的分析物和流动相的特定行为。特别是，在流动相的低洗脱强度和高洗脱强度下，由于保留因子和床层扩散率对 B 项的贡献占主导地位，因此观察到 U 型 B 项曲线。
{"title":"Multiscale simulation of liquid chromatography: Effective diffusion in macro–mesoporous beds and the B-term of the plate height equation","authors":"Ulrich Tallarek, Dzmitry Hlushkou, Andreas Steinhoff, Alexandra Höltzel","doi":"10.1016/j.chroma.2024.465468","DOIUrl":"10.1016/j.chroma.2024.465468","url":null,"abstract":"<div><div>We performed multiscale simulations of analyte sorption and diffusion in hierarchical porosity models of monolithic silica columns for reversed-phase liquid chromatography to investigate how the mean mesopore size of the chromatographic bed and the analyte-specific interaction with the chromatographic interface influence the analyte diffusivity at various length scales. The reproduced experimental conditions comprised the retention of six analyte compounds of low to moderate solute polarity on a silica-based, endcapped, C<sub>18</sub> stationary phase with water‒acetonitrile and water–methanol mobile phases whose elution strength was varied via the volumetric solvent ratio. Detailed information about the analyte-specific interfacial dynamics received from molecular dynamics simulations was incorporated through appropriate linker schemes into Brownian dynamics diffusion simulations in three hierarchical porosity models received from physical reconstructions of silica monoliths with a mean macropore size of 1.23 µm and mean mesopore sizes of 12.3, 21.3, or 25.7 nm. The mean mesopore size was found to have a similar influence on the effective mesopore diffusivity as the analyte polarity and the mobile-phase elution strength, which together determine the analyte residence time on a column. A smaller mesopore size attenuated the increase of the effective mesopore diffusivity with increasing mobile-phase elution strength significantly. The effective bed diffusivity was limited by the analyte residence time rather than by morphological details of the mesopore space. The stronger an analyte was retained by the chromatographic interface inside the mesopores, the slower became the mass transfer between the pore space hierarchies and the lower was the effective bed diffusivity. The B-terms of the plate height equation were finally generated with the bed diffusivities and phase-based retention factors derived from the hierarchical porosity models using additional information about the stationary-phase limit obtained from the analysis of analyte–bonded phase contacts. The B-terms highlight analyte- and mobile phase-specific behavior relevant to isocratic and gradient elution conditions in chromatographic practice. In particular, U-shaped B-term curves are observed due to the dominating contribution of the retention factor and the bed diffusivity to the B-term at low and high elution strength of the mobile phase, respectively.</div></div>","PeriodicalId":347,"journal":{"name":"Journal of Chromatography A","volume":"1738 ","pages":"Article 465468"},"PeriodicalIF":3.8,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142556802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Multifunctional materials, such as restricted access molecularly imprinted polymers covered with bovine serum albumin (RAMIP-BSA), are effective alternatives for sample preparation techniques. This material selectively adsorbs analytes while excluding macromolecules, enhancing the analysis's efficiency. Among analytical techniques, ESI-MS/MS (Electrospray Ionization-Tandem Mass Spectrometry) has successfully identified and quantified various molecules, including trace-level drugs. Therefore, we proposed, for the first time, an integrated online extraction/analysis system that combines the benefits of RAMIP-BSA and ESI-MS/MS for analyzing mebendazole (MBZ) and albendazole (ABZ) in milk samples without the need for chromatographic separation. Initially, a RAMIP selective for MBZ was synthesized using the bulk method with methacrylic acid and glycidyl methacrylate. Then, the polymer was covered with bovine serum albumin. Subsequently, this adsorbent was packed in a small column and coupled with an ESI-MS/MS instrument in an online configuration. Milli-Q water was used as the loading and reconditioning mobile phases, and a solution of formic acid in methanol (1:100 v/v) was employed as the elution phase. The system enabled simultaneous extraction and determination of MBZ and ABZ in milk samples. The method exhibited linearity between 15.0 and 125.0 μg L−1 for MBZ and 10.0 and 125.0 μg L−1 for ABZ (with a correlation coefficient exceeding 0.99). The limits of quantification were 15.0 and 10.0 μg L−1 for MBZ and ABZ, respectively. Good precision and accuracy were achieved. The developed method was used to analyze MBZ and ABZ in real milk samples and proved to be a viable alternative to conventional sample preparation and chromatographic techniques.
{"title":"Online restricted access molecularly imprinted solid phase extraction coupled with electrospray ionization-tandem mass spectrometry for determination of mebendazole and albendazole in milk samples","authors":"Amanda Aparecida Marques Lourêdo , Helton Hanchuck Pereira , Rudy Bonfilio , Mariane Gonçalves Santos","doi":"10.1016/j.chroma.2024.465466","DOIUrl":"10.1016/j.chroma.2024.465466","url":null,"abstract":"<div><div>Multifunctional materials, such as restricted access molecularly imprinted polymers covered with bovine serum albumin (RAMIP-BSA), are effective alternatives for sample preparation techniques. This material selectively adsorbs analytes while excluding macromolecules, enhancing the analysis's efficiency. Among analytical techniques, ESI-MS/MS (Electrospray Ionization-Tandem Mass Spectrometry) has successfully identified and quantified various molecules, including trace-level drugs. Therefore, we proposed, for the first time, an integrated online extraction/analysis system that combines the benefits of RAMIP-BSA and ESI-MS/MS for analyzing mebendazole (MBZ) and albendazole (ABZ) in milk samples without the need for chromatographic separation. Initially, a RAMIP selective for MBZ was synthesized using the bulk method with methacrylic acid and glycidyl methacrylate. Then, the polymer was covered with bovine serum albumin. Subsequently, this adsorbent was packed in a small column and coupled with an ESI-MS/MS instrument in an online configuration. Milli-Q water was used as the loading and reconditioning mobile phases, and a solution of formic acid in methanol (1:100 v/v) was employed as the elution phase. The system enabled simultaneous extraction and determination of MBZ and ABZ in milk samples. The method exhibited linearity between 15.0 and 125.0 μg L<sup>−1</sup> for MBZ and 10.0 and 125.0 μg L<sup>−1</sup> for ABZ (with a correlation coefficient exceeding 0.99). The limits of quantification were 15.0 and 10.0 μg L<sup>−1</sup> for MBZ and ABZ, respectively. Good precision and accuracy were achieved. The developed method was used to analyze MBZ and ABZ in real milk samples and proved to be a viable alternative to conventional sample preparation and chromatographic techniques.</div></div>","PeriodicalId":347,"journal":{"name":"Journal of Chromatography A","volume":"1737 ","pages":"Article 465466"},"PeriodicalIF":3.8,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142542588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-22DOI: 10.1016/j.chroma.2024.465469
Leon E. Niezen , Deirdre Cabooter , Gert Desmet
An alternative strategy is explored for the separation of samples by liquid chromatography (LC). Unlike traditional approaches that aim to resolve all components in a given sample within a single LC separation, the proposed strategy uses two or more distinct separations carried out with a different gradient program and/or using different separation chemistries i.e., a different set of mobile and stationary phase. This set of complementary incomplete separations (CIS) is selected such that each component is at least fully resolved once, meaning the most critical pairs of each individual separation can be left unseparated. This allows for a significant time saving per separation. To investigate whether such an approach can lead to overall shorter analysis times than is possible with the fastest single-run gradient separation, a comprehensive in silico study covering a statistically significant number of samples is undertaken. The investigation shows that, for the presently considered sample sets and chemistries, CIS has a substantially higher probability, about two times greater for the simplest samples considered in this work and as much as 30 times greater for more complex samples, to fully resolve an unknown sample compared to a single gradient separation. Comparing separation speeds, the CIS approach can achieve complete sample resolution on average approximately four times faster than a single separation. Our findings thus demonstrate the potential of CIS in enhancing separation efficiency and offer insights regarding their use for solving analytical challenges.
{"title":"Exploring the utility of complementary separations in liquid chromatography","authors":"Leon E. Niezen , Deirdre Cabooter , Gert Desmet","doi":"10.1016/j.chroma.2024.465469","DOIUrl":"10.1016/j.chroma.2024.465469","url":null,"abstract":"<div><div>An alternative strategy is explored for the separation of samples by liquid chromatography (LC). Unlike traditional approaches that aim to resolve all components in a given sample within a single LC separation, the proposed strategy uses two or more distinct separations carried out with a different gradient program and/or using different separation chemistries <em>i.e.,</em> a different set of mobile and stationary phase. This set of complementary incomplete separations (CIS) is selected such that each component is at least fully resolved once, meaning the most critical pairs of each individual separation can be left unseparated. This allows for a significant time saving per separation. To investigate whether such an approach can lead to overall shorter analysis times than is possible with the fastest single-run gradient separation, a comprehensive <em>in silico</em> study covering a statistically significant number of samples is undertaken. The investigation shows that, for the presently considered sample sets and chemistries, CIS has a substantially higher probability, about two times greater for the simplest samples considered in this work and as much as 30 times greater for more complex samples, to fully resolve an unknown sample compared to a single gradient separation. Comparing separation speeds, the CIS approach can achieve complete sample resolution on average approximately four times faster than a single separation. Our findings thus demonstrate the potential of CIS in enhancing separation efficiency and offer insights regarding their use for solving analytical challenges.</div></div>","PeriodicalId":347,"journal":{"name":"Journal of Chromatography A","volume":"1738 ","pages":"Article 465469"},"PeriodicalIF":3.8,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142563886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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