Pub Date : 2022-01-01DOI: 10.15826/analitika.2022.26.1.001
D. Makeeva, K. Antipova, L. Kartsova
Electrophoretic separation and on-line concentration of short-chain fatty acids (SCFAs) in human blood serum of the patients with the inflammatory bowel disease is described in the current investigation. SCFAs are end products of carbohydrate fermentation, which are indigestible in the intestine. The highest concentrations of SCFAs are in the proximal colon, where they are absorbed by the epithelial cells of the colon (colonocytes) and then enter the tissues and blood. The changes in their serum content can indicate the metabolism disorders and inflammatory bowel diseases. The low sensitivity of capillary electrophoresis requires application of on-line concentration in order to implement this method for the detection of low concentrations of SCFAs in biological fluids. Moreover, for the salt-matrix samples, an application of common concentration techniques based on the differences in conductivity of sample matrix and background electrolyte is limited. Therefore, the development of fast, efficient and highly sensitive approaches for the determination of SCFAs in blood serum is an important task. In the current work, the improvement of the sensitivity of SFCAs has been achieved by the application of a water plug, which was proposed to be injected directly before the sample in order to form a low conductivity area for the acceleration and concentration of the analytes. The proposed preconcentration and electrophoretic separation scheme provided decreased detection limits of SCFAs (~ 50 - 70 ng/mL) due to 30 times concentration of analytes as well as fast analytes’ determination (15 min).
{"title":"Electrophoretic determination of carboxylic acids in blood serum with intracapillary concentration","authors":"D. Makeeva, K. Antipova, L. Kartsova","doi":"10.15826/analitika.2022.26.1.001","DOIUrl":"https://doi.org/10.15826/analitika.2022.26.1.001","url":null,"abstract":"Electrophoretic separation and on-line concentration of short-chain fatty acids (SCFAs) in human blood serum of the patients with the inflammatory bowel disease is described in the current investigation. SCFAs are end products of carbohydrate fermentation, which are indigestible in the intestine. The highest concentrations of SCFAs are in the proximal colon, where they are absorbed by the epithelial cells of the colon (colonocytes) and then enter the tissues and blood. The changes in their serum content can indicate the metabolism disorders and inflammatory bowel diseases. The low sensitivity of capillary electrophoresis requires application of on-line concentration in order to implement this method for the detection of low concentrations of SCFAs in biological fluids. Moreover, for the salt-matrix samples, an application of common concentration techniques based on the differences in conductivity of sample matrix and background electrolyte is limited. Therefore, the development of fast, efficient and highly sensitive approaches for the determination of SCFAs in blood serum is an important task. In the current work, the improvement of the sensitivity of SFCAs has been achieved by the application of a water plug, which was proposed to be injected directly before the sample in order to form a low conductivity area for the acceleration and concentration of the analytes. The proposed preconcentration and electrophoretic separation scheme provided decreased detection limits of SCFAs (~ 50 - 70 ng/mL) due to 30 times concentration of analytes as well as fast analytes’ determination (15 min).","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67254029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.15826/analitika.2022.26.2.001
H. Vu, A. Zyablov
In the current study, piezosensors based on the molecularly imprinted polyimides with imprints of potassium sorbate and sodium benzoate were obtained. Molecularly Imprinted Polymers (MIPs) were synthesized using a polyimide and a non-covalent imprinting technique. It was established that the use of 0.1 g/mL template concentration at the thermochemical stage led to the formation of the maximum number of molecular imprints on the film surface. Using the scanning force microscopy, it was found that the reference polymer film had a uniform surface with a small height difference from 1.4 to 2.6 nm (including 88.94 % of pores with a radius of up to 10 nm) and had good film thickness reproducibility. The surface morphology of films of molecularly imprinted polymers with imprints of potassium sorbate and sodium benzoate had more developed surface, which was associated with the peculiarities of the formation of imprints. In this work, imprinting factor (IF) and selectivity coefficient (k) of the sensor were calculated. Molecularly imprinted polymers had better selectivity, sensitivity, and ability to recognize target template molecules than the reference polymers (non-imprinted polymers). Molecularly imprinted polymer-modified piezoelectric sensors (MIP sensors) have been used to analyze potassium sorbate and sodium benzoate in non-alcoholic drinks. The linear concentration range was identified to be 5 - 500 mg/L and the limit of detection for potassium sorbate and sodium benzoate were 1.6 mg/L and 2 mg/L, respectively. The determination of potassium sorbate and sodium benzoate in non-alcoholic drinks was carried out by MIP sensors and spectrophotometry method. The results obtained by the sensors and the spectrophotometry method were in good agreement. The concentration of preservatives for the potassium sorbate and the sodium benzoate in non-alcoholic drinks was 130 - 176 mg/L and 129 - 146 mg/L, respectively.
{"title":"Determination of preservatives in liquids by piezosensors","authors":"H. Vu, A. Zyablov","doi":"10.15826/analitika.2022.26.2.001","DOIUrl":"https://doi.org/10.15826/analitika.2022.26.2.001","url":null,"abstract":"In the current study, piezosensors based on the molecularly imprinted polyimides with imprints of potassium sorbate and sodium benzoate were obtained. Molecularly Imprinted Polymers (MIPs) were synthesized using a polyimide and a non-covalent imprinting technique. It was established that the use of 0.1 g/mL template concentration at the thermochemical stage led to the formation of the maximum number of molecular imprints on the film surface. Using the scanning force microscopy, it was found that the reference polymer film had a uniform surface with a small height difference from 1.4 to 2.6 nm (including 88.94 % of pores with a radius of up to 10 nm) and had good film thickness reproducibility. The surface morphology of films of molecularly imprinted polymers with imprints of potassium sorbate and sodium benzoate had more developed surface, which was associated with the peculiarities of the formation of imprints. In this work, imprinting factor (IF) and selectivity coefficient (k) of the sensor were calculated. Molecularly imprinted polymers had better selectivity, sensitivity, and ability to recognize target template molecules than the reference polymers (non-imprinted polymers). Molecularly imprinted polymer-modified piezoelectric sensors (MIP sensors) have been used to analyze potassium sorbate and sodium benzoate in non-alcoholic drinks. The linear concentration range was identified to be 5 - 500 mg/L and the limit of detection for potassium sorbate and sodium benzoate were 1.6 mg/L and 2 mg/L, respectively. The determination of potassium sorbate and sodium benzoate in non-alcoholic drinks was carried out by MIP sensors and spectrophotometry method. The results obtained by the sensors and the spectrophotometry method were in good agreement. The concentration of preservatives for the potassium sorbate and the sodium benzoate in non-alcoholic drinks was 130 - 176 mg/L and 129 - 146 mg/L, respectively.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67254879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.15826/analitika.2022.26.4.004
U. G. Gamzaeva, K. Mirzaeva, R. Z. Zeynalov
Quaternary ammonium compounds, and among them cetylpyridinium salts (CP) in particular, are widely used as antiseptics and disinfectants, for local treatment of infectious and inflammatory processes of the mucous membrane of the throat and oral cavity, as constituents of lozenges, gels and oral hygiene products. This paper proposes conditions for determination of cetylpyridinium chloride, which has an antimicrobial effect, in some surfactant-containing pharmaceutical preparations approved for the medical use, using solid-state spectrophotometry and a test method. Linen fabric (LN) was used as a solid matrix. The paper shows the efficiency of sorption extraction of cetylpyridinium chloride in the form of the ion associate with the organic azo dye sulfonazo (SFN). Analysis of the absorption spectra of solid-state systems [LN-SFN] and LN-[SFN-CP] showed that the reagent was practically not extracted at pH ≥ 4, but in the presence of CP the sorption was observed over the entire pH range studied with the maximum at pHmax = 5. For the proposed test method, the range of determined concentrations of CP was 1.0–16 mg/dm3 and the limit of detection was 0.4 mg/dm3; for the solid-state spectrophotometric determination, the range of determined CP concentrations was 0.5–24 mg/dm3 and the detection limit was 0.2 mg/dm3. The possibility of determining the CP in real objects was demonstrated.
{"title":"DETERMINATION OF CETYLPYRIDINIUM CHLORIDE IN PHARMACEUTICAL PREPARATIONS BY SOLID-STATE SPECTROPHOTOMETRY METHOD","authors":"U. G. Gamzaeva, K. Mirzaeva, R. Z. Zeynalov","doi":"10.15826/analitika.2022.26.4.004","DOIUrl":"https://doi.org/10.15826/analitika.2022.26.4.004","url":null,"abstract":"Quaternary ammonium compounds, and among them cetylpyridinium salts (CP) in particular, are widely used as antiseptics and disinfectants, for local treatment of infectious and inflammatory processes of the mucous membrane of the throat and oral cavity, as constituents of lozenges, gels and oral hygiene products. This paper proposes conditions for determination of cetylpyridinium chloride, which has an antimicrobial effect, in some surfactant-containing pharmaceutical preparations approved for the medical use, using solid-state spectrophotometry and a test method. Linen fabric (LN) was used as a solid matrix. The paper shows the efficiency of sorption extraction of cetylpyridinium chloride in the form of the ion associate with the organic azo dye sulfonazo (SFN). Analysis of the absorption spectra of solid-state systems [LN-SFN] and LN-[SFN-CP] showed that the reagent was practically not extracted at pH ≥ 4, but in the presence of CP the sorption was observed over the entire pH range studied with the maximum at pHmax = 5. For the proposed test method, the range of determined concentrations of CP was 1.0–16 mg/dm3 and the limit of detection was 0.4 mg/dm3; for the solid-state spectrophotometric determination, the range of determined CP concentrations was 0.5–24 mg/dm3 and the detection limit was 0.2 mg/dm3. The possibility of determining the CP in real objects was demonstrated.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67255031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.15826/analitika.2022.26.3.004
I. Stepanova, A. V. Shik, E. Skorobogatov, A. A. Bartoshevich, M. Beklemishev
It was found that the commercial carbocyanine dye IR-783 containing sulfo groups forms aggregates with cetyltrimethylammonium bromide (CTAB) in a slightly alkaline medium yielding a new absorption band, a change in the solution color from blue to yellow (Dl = 350 nm), and a change in the fluorescence intensity in the near-IR region. CTAB was determined by the photometric method by photographing the reaction mixture in a 96-well plate with a smartphone camera or in a Camag visualizer. The difference between the intensities of the red and blue channels (R – B), corresponding to the yellow color, was used as an analytical signal. The linear range in an aqueous solution is (3 – 25)·10–6 M, the detection limit is 1.6·10–6 M, and the relative standard deviation is 2–5%. The determination is not affected with a number of non-ionic surfactants, inorganic salts and polymers; the anionic surfactants interfere. Other cationic surfactants also give analytical signals, but with different sensitivities. The characteristics of the literature method for the determination of CTAB based on the Coomassie brilliant blue G-250 dye and the proposed method are comparable. A sample of CTAB-containing lysing buffer solution was analyzed.
{"title":"Colorimetric determination of cetyltrimethylammonium bromide by using aggregation with a carbocyanine dye","authors":"I. Stepanova, A. V. Shik, E. Skorobogatov, A. A. Bartoshevich, M. Beklemishev","doi":"10.15826/analitika.2022.26.3.004","DOIUrl":"https://doi.org/10.15826/analitika.2022.26.3.004","url":null,"abstract":"It was found that the commercial carbocyanine dye IR-783 containing sulfo groups forms aggregates with cetyltrimethylammonium bromide (CTAB) in a slightly alkaline medium yielding a new absorption band, a change in the solution color from blue to yellow (Dl = 350 nm), and a change in the fluorescence intensity in the near-IR region. CTAB was determined by the photometric method by photographing the reaction mixture in a 96-well plate with a smartphone camera or in a Camag visualizer. The difference between the intensities of the red and blue channels (R – B), corresponding to the yellow color, was used as an analytical signal. The linear range in an aqueous solution is (3 – 25)·10–6 M, the detection limit is 1.6·10–6 M, and the relative standard deviation is 2–5%. The determination is not affected with a number of non-ionic surfactants, inorganic salts and polymers; the anionic surfactants interfere. Other cationic surfactants also give analytical signals, but with different sensitivities. The characteristics of the literature method for the determination of CTAB based on the Coomassie brilliant blue G-250 dye and the proposed method are comparable. A sample of CTAB-containing lysing buffer solution was analyzed.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67255472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.15826/analitika.2022.26.3.005
A. Shcherbatykh, O. I. Askalepova, I. A. Estrin
Biological low-molecular aminothiols, such as homocysteine, are characterized by the weak absorption in the UV – visible range. Therefore, aminothiols analysis requires using thiol-specific chemosensors or derivatization procedure. Heterocyclic disulfides belong to a large group of derivatizing agents. However, the disulfides widely used in the analytical practice, such as 5,5'-dithiobis-(2-nitrobenzoic acid), have several disadvantages: limited acceptable pH range, low sensitivity, susceptibility to hydrolisys. Hence, the search for the effective derivatizing agents continues. In the current work, 2,2'-dithiobis[benzoxazole] and 8,8'-dithiobis-quinoline disulfides were used for the analysis of homocysteine. Precise and sensitive methods (homocysteine detection limit in the range of 1.1·10-6–7.8·10-6 M, relative standard deviation in the range of 1.5–4.6%) for the homocysteine determination have been developed, including spectrophotometric method, capillary electrophoresis (CE), high-performance liquid chromatography (HPLC) and kinetic method with the spectrophotometric detection. The proposed disulfides have also been successfully used in the analysis of sulfhydryl groups content in the sample of human urine.
{"title":"Analysis of homocysteine and thiol-containing compounds using the heterocyclic disulfides","authors":"A. Shcherbatykh, O. I. Askalepova, I. A. Estrin","doi":"10.15826/analitika.2022.26.3.005","DOIUrl":"https://doi.org/10.15826/analitika.2022.26.3.005","url":null,"abstract":"Biological low-molecular aminothiols, such as homocysteine, are characterized by the weak absorption in the UV – visible range. Therefore, aminothiols analysis requires using thiol-specific chemosensors or derivatization procedure. Heterocyclic disulfides belong to a large group of derivatizing agents. However, the disulfides widely used in the analytical practice, such as 5,5'-dithiobis-(2-nitrobenzoic acid), have several disadvantages: limited acceptable pH range, low sensitivity, susceptibility to hydrolisys. Hence, the search for the effective derivatizing agents continues. In the current work, 2,2'-dithiobis[benzoxazole] and 8,8'-dithiobis-quinoline disulfides were used for the analysis of homocysteine. Precise and sensitive methods (homocysteine detection limit in the range of 1.1·10-6–7.8·10-6 M, relative standard deviation in the range of 1.5–4.6%) for the homocysteine determination have been developed, including spectrophotometric method, capillary electrophoresis (CE), high-performance liquid chromatography (HPLC) and kinetic method with the spectrophotometric detection. The proposed disulfides have also been successfully used in the analysis of sulfhydryl groups content in the sample of human urine.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67255478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.15826/analitika.2022.26.1.004
I. Zenkevich, A. Derouiche
As a result of the determination of retention indices (RI) of 11 organic compounds of various polarity in reversed phase (RP) HPLC using methanol as organic solvent in eluent, the coefficients of the dependence of RI vs. content of methanol, dRI/dС were determined. Formally, these parameters are equivalent to the temperature coefficients of gas chromatographic retention indices, b = dRI/dT. It is shown that the ranges of variations of these coefficients are rather large (from -2.0 up to +4.6 in the current work), which requires revealing the factors influencing their signs and absolute values. The correlations of coefficients dRI/dC with retention indices themselves, as well as with hydrophobicity factors, logP (the logarithms of partition coefficients in the system 1-octanol/water) seem to be negligible. The best correlations of dRI/dC were observed with such polarity measures of organic compounds as homologous increments of hydrophobicity factors (ilogP), and retention indices (iRI). Such transformations of properties A as their homologous increments characterize different homologues despite of their locations within the homologous series. Thus, the parameters ilogP and iRI appeared to be the measures of the polarity of the corresponding series. This approach permits us to reveal that the dependence of retention indices in RP HPLC on the content of methanol in eluent is determined just by the analytes¢ polarity and their hydrophobic – hydrophilic properties. The ratio dRI/dC > 0 is typical for non-polar analytes, while for polar compounds the negative signs of these coefficients are typical, dRI/dC < 0. Hence, determining even the sign of this coefficient provides the important information on the chemical origin of analytes.
以甲醇为有机溶剂，采用反相高效液相色谱法测定了11种不同极性有机化合物的保留指数(RI)，得到了RI与甲醇含量(dRI/dС)的依赖系数。形式上，这些参数相当于气相色谱保留指数的温度系数b = dRI/dT。结果表明，这些系数的变化范围相当大(在当前的工作中从-2.0到+4.6)，这需要重新研究影响其符号和绝对值的因素。系数- ci - ents dRI/dC与保留指数本身的相关性，以及与疏水性因子logP(系统中1-辛醇/水分配系数的对数)的相关性似乎可以忽略不计。有机化合物的疏水因子(ilogP)的同源增量和再保留指数(iRI)等极性测量值与dRI/dC的相关性最好。性质A作为其同源增量的这种变换表征不同的同源物，尽管它们在同源序列中的位置不同。因此，参数ilogP和iRI似乎是对对应-脉冲序列极性的度量。该方法揭示了反相高效液相色谱中保留指标对洗脱液中甲基萘酚含量的依赖关系仅由分析物的纯度及其疏-亲水性决定。对于非极性分析物，dRI/dC比值>是典型的，而对于极性化合物，这些系数的负符号是典型的，dRI/dC < 0。因此，即使确定这个系数的符号，也提供了分析物化学来源的重要信息。
{"title":"Analytical aspects of organic compounds retention indices dependence in reversed phase HPLC on the content of methanol in eluent","authors":"I. Zenkevich, A. Derouiche","doi":"10.15826/analitika.2022.26.1.004","DOIUrl":"https://doi.org/10.15826/analitika.2022.26.1.004","url":null,"abstract":"As a result of the determination of retention indices (RI) of 11 organic compounds of various polarity in reversed phase (RP) HPLC using methanol as organic solvent in eluent, the coefficients of the dependence of RI vs. content of methanol, dRI/dС were determined. Formally, these parameters are equivalent to the temperature coefficients of gas chromatographic retention indices, b = dRI/dT. It is shown that the ranges of variations of these coefficients are rather large (from -2.0 up to +4.6 in the current work), which requires revealing the factors influencing their signs and absolute values. The correlations of coefficients dRI/dC with retention indices themselves, as well as with hydrophobicity factors, logP (the logarithms of partition coefficients in the system 1-octanol/water) seem to be negligible. The best correlations of dRI/dC were observed with such polarity measures of organic compounds as homologous increments of hydrophobicity factors (ilogP), and retention indices (iRI). Such transformations of properties A as their homologous increments characterize different homologues despite of their locations within the homologous series. Thus, the parameters ilogP and iRI appeared to be the measures of the polarity of the corresponding series. This approach permits us to reveal that the dependence of retention indices in RP HPLC on the content of methanol in eluent is determined just by the analytes¢ polarity and their hydrophobic – hydrophilic properties. The ratio dRI/dC > 0 is typical for non-polar analytes, while for polar compounds the negative signs of these coefficients are typical, dRI/dC < 0. Hence, determining even the sign of this coefficient provides the important information on the chemical origin of analytes.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67254836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.15826/analitika.2022.26.1.009
Z. Temerdashev, P. Abakumov, D. Abakumova
The paper considers the possibility of determining the total content of tin in various forms of presence in the waters of the Azov and Black Seas, which differ in salinity. Organotin compounds, when present in waters, interfere with the determination of inorganic forms of tin by direct injection by ICP spectrometry. It is shown that before determining the total content of tin in various forms of presence in waters with organotin compounds, microwave mineralization of the analyzed samples is required, under which a quantitative conversion to the inorganic form of tin is ensured. The highest efficiency of decomposition of water samples was achieved using oxidizing mixtures based on nitric acid (5.0 см3 HNO3; 4.0 см3 HNO3 + 1.0 см3 HCl и 3.0 см3 HNO3 + 2.0 см3 H2О2). Limits for the determination of tin (LOQSn) in solutions prepared in deionized and model sea waters with different salinities have been established. According to the proposed scheme of analysis for ICP-AES, the LOQSn values in water samples from the Azov and Black Seas were 0.40 and 0.47 µg/dm3, respectively, with direct injection of the sample. In the ICP-MS determination of LOQSn also increases with increasing water salinity and ranges from 0.03 (deionized water) to 0.45 μg/dm3 (model sea water with a salinity of 18 ‰). The developed scheme of analysis made it possible to determine the total content of tin, considering all forms of its presence in sea waters. Satisfactory convergence of the results of analyzes after microwave mineralization of waters is observed for ICP-AES determination of the total tin content in the range from 0.45 to 10.0 μg/dm3, and for ICP-MS in the range from 0.40 to 5.00 μg/dm3. In the analyzed water samples of the Azov and Black Seas, the total tin content was found to be 0.20 and 0.23 µg/dm3, respectively.
{"title":"ICP-spectrometric determination of the total tin content in the water of the Azov and Black Seas","authors":"Z. Temerdashev, P. Abakumov, D. Abakumova","doi":"10.15826/analitika.2022.26.1.009","DOIUrl":"https://doi.org/10.15826/analitika.2022.26.1.009","url":null,"abstract":"The paper considers the possibility of determining the total content of tin in various forms of presence in the waters of the Azov and Black Seas, which differ in salinity. Organotin compounds, when present in waters, interfere with the determination of inorganic forms of tin by direct injection by ICP spectrometry. It is shown that before determining the total content of tin in various forms of presence in waters with organotin compounds, microwave mineralization of the analyzed samples is required, under which a quantitative conversion to the inorganic form of tin is ensured. The highest efficiency of decomposition of water samples was achieved using oxidizing mixtures based on nitric acid (5.0 см3 HNO3; 4.0 см3 HNO3 + 1.0 см3 HCl и 3.0 см3 HNO3 + 2.0 см3 H2О2). Limits for the determination of tin (LOQSn) in solutions prepared in deionized and model sea waters with different salinities have been established. According to the proposed scheme of analysis for ICP-AES, the LOQSn values in water samples from the Azov and Black Seas were 0.40 and 0.47 µg/dm3, respectively, with direct injection of the sample. In the ICP-MS determination of LOQSn also increases with increasing water salinity and ranges from 0.03 (deionized water) to 0.45 μg/dm3 (model sea water with a salinity of 18 ‰). The developed scheme of analysis made it possible to determine the total content of tin, considering all forms of its presence in sea waters. Satisfactory convergence of the results of analyzes after microwave mineralization of waters is observed for ICP-AES determination of the total tin content in the range from 0.45 to 10.0 μg/dm3, and for ICP-MS in the range from 0.40 to 5.00 μg/dm3. In the analyzed water samples of the Azov and Black Seas, the total tin content was found to be 0.20 and 0.23 µg/dm3, respectively.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67254986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.15826/analitika.2022.26.3.001
Z. Temerdashev, P. Abakumov, D. Abakumova
In the current paper, the possibility of separating inorganic and organic forms of tin occurrences has been considered and the features of determining the total content of organotin compounds (OTC) in waters with different salinities by ICP-spectrometry with hydride generation were studied. Various approaches to the separation of the chemical forms of tin by liquid-liquid extraction with various solvents, as well as by precipitation with fluorides, iodides, aqueous solutions of ammonia and iron (III) chloride at analyte concentrations at the MPC level for fishery reservoirs, have been examined. The separation of the chemical forms of tin due to the taking out the OTC by liquid-liquid extraction turned out to be inefficient because of the incomplete extraction of analytes and partial extraction (up to 15%) of the inorganic form of tin into the organic phase. Precipitation of inorganic and organic forms of tin using fluorides, iodides, ammonia, and iron (III) chloride also turned out to be inefficient. This was due to the low content of analytes, at which their quantitative precipitation was difficult. Under the conditions of high-level mineralization of sea waters, it was also unlikely that a competing reaction of changing the chloride environment to fluoride or iodide one would occur. Separation of the chemical forms of tin was achieved using the solid phase sorption. The Diapak C18 silica gel sorbent selectively extracted the organic form of tin from waters with different salinity under the optimized conditions. The optimized conditions for separating the chemical forms of tin made it possible to develop a method for determining the total content of OTC in natural waters with different salinity from the difference between the total content of the analyte and the inorganic form of tin. To determine the total content of the analyte, microwave mineralization of the water sample was carried out; the concentration of the inorganic form of tin was determined after its solid-phase separation from organotin compounds. The lower limits of analyte concentrations determined were 0.03 and 0.05 μg/dm3 for the ICP-MS and ICP-AES methods, respectively, which made it possible to separately determine the OTC during the ecoanalytical monitoring at the level below the MPC.
{"title":"Separation of the tin finding forms and determination of the organotin compounds total content in natural waters of different salinity","authors":"Z. Temerdashev, P. Abakumov, D. Abakumova","doi":"10.15826/analitika.2022.26.3.001","DOIUrl":"https://doi.org/10.15826/analitika.2022.26.3.001","url":null,"abstract":"In the current paper, the possibility of separating inorganic and organic forms of tin occurrences has been considered and the features of determining the total content of organotin compounds (OTC) in waters with different salinities by ICP-spectrometry with hydride generation were studied. Various approaches to the separation of the chemical forms of tin by liquid-liquid extraction with various solvents, as well as by precipitation with fluorides, iodides, aqueous solutions of ammonia and iron (III) chloride at analyte concentrations at the MPC level for fishery reservoirs, have been examined. The separation of the chemical forms of tin due to the taking out the OTC by liquid-liquid extraction turned out to be inefficient because of the incomplete extraction of analytes and partial extraction (up to 15%) of the inorganic form of tin into the organic phase. Precipitation of inorganic and organic forms of tin using fluorides, iodides, ammonia, and iron (III) chloride also turned out to be inefficient. This was due to the low content of analytes, at which their quantitative precipitation was difficult. Under the conditions of high-level mineralization of sea waters, it was also unlikely that a competing reaction of changing the chloride environment to fluoride or iodide one would occur. Separation of the chemical forms of tin was achieved using the solid phase sorption. The Diapak C18 silica gel sorbent selectively extracted the organic form of tin from waters with different salinity under the optimized conditions. The optimized conditions for separating the chemical forms of tin made it possible to develop a method for determining the total content of OTC in natural waters with different salinity from the difference between the total content of the analyte and the inorganic form of tin. To determine the total content of the analyte, microwave mineralization of the water sample was carried out; the concentration of the inorganic form of tin was determined after its solid-phase separation from organotin compounds. The lower limits of analyte concentrations determined were 0.03 and 0.05 μg/dm3 for the ICP-MS and ICP-AES methods, respectively, which made it possible to separately determine the OTC during the ecoanalytical monitoring at the level below the MPC.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67255375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.15826/analitika.2022.26.3.002
M. Sorvin, A. Saveliev, I. Stoikov, S. Belyakova, G. Evtugyn
Determination of halogenide ions in pharmaceuticals and various waters is an actual task for the modern analytical chemistry. In the current work, solid-contact potentiometric sensor, based on the glassy carbon electrode covered with the layer of electropolymerized polyaniline and suspension of silver nanoparticles in the matrix of thiacalix[4]arene derivative bearing terminal catechol groups, has been described. The suspension was obtained by the chemical reduction of silver ions with the thiacalix[4]arene and drop casted on the polyaniline layer. The sensor showed potentiometric response to chloride-, bromide and iodide ions. For the simultaneous determination of iodide and bromide ions, a multi-sensor system, consisting of four electrodes with the different volumes of the suspension placed on the polyaniline layer, has been developed. The possibility of the response prediction within the simple additive model was found for the set of the iodide and bromide mixtures. In a similar manner, simultaneous determination of both ions in the variable mixtures has been performed. The multi-sensor system was tested during the determination of iodides in iodine containing pharmaceuticals and the determination of iodide and bromide ions in the artificial mineral water samples. Ionic chromatography was chosen as the comparison method. Sensors made it possible to determine from 0.1 μM to10 mMiodide and bromide ions in mixtures. The proposed approach and solid-contact potentiometric sensors can be used in the analysis of ion content of the waters and in control of the production and storage conditions of pharmaceuticals.
{"title":"Solid-contact potentiometric sensors based on silver nanoparticles in the supramolecular matrix for the determination of halogenide ions","authors":"M. Sorvin, A. Saveliev, I. Stoikov, S. Belyakova, G. Evtugyn","doi":"10.15826/analitika.2022.26.3.002","DOIUrl":"https://doi.org/10.15826/analitika.2022.26.3.002","url":null,"abstract":"Determination of halogenide ions in pharmaceuticals and various waters is an actual task for the modern analytical chemistry. In the current work, solid-contact potentiometric sensor, based on the glassy carbon electrode covered with the layer of electropolymerized polyaniline and suspension of silver nanoparticles in the matrix of thiacalix[4]arene derivative bearing terminal catechol groups, has been described. The suspension was obtained by the chemical reduction of silver ions with the thiacalix[4]arene and drop casted on the polyaniline layer. The sensor showed potentiometric response to chloride-, bromide and iodide ions. For the simultaneous determination of iodide and bromide ions, a multi-sensor system, consisting of four electrodes with the different volumes of the suspension placed on the polyaniline layer, has been developed. The possibility of the response prediction within the simple additive model was found for the set of the iodide and bromide mixtures. In a similar manner, simultaneous determination of both ions in the variable mixtures has been performed. The multi-sensor system was tested during the determination of iodides in iodine containing pharmaceuticals and the determination of iodide and bromide ions in the artificial mineral water samples. Ionic chromatography was chosen as the comparison method. Sensors made it possible to determine from 0.1 μM to10 mMiodide and bromide ions in mixtures. The proposed approach and solid-contact potentiometric sensors can be used in the analysis of ion content of the waters and in control of the production and storage conditions of pharmaceuticals.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67255458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.15826/analitika.2022.26.4.005
R. Chuvashov, D. Belyaev, K. Khokhlov, A. Baranova, M. Zen Eddin, I. Milman, E. Verbitskiy
Integration of fluorescent substances into polymeric matrices can improve their sensory properties and photostability. In this work, fluorescent materials based on fluorophore-doped polystyrene were obtained and characterized as sensors towards the ecotoxicant nitrobenzene in gas phase. Melamine-formaldehyde foam has been proposed as a permeable substrate for the sensor material deposition applicable for gas-phase measurements. The effect on sensor properties of the porous material surface obtained via Breath Figure pore generation technique was investigated. Limits of detection and calibration relationships of obtained materials towards nitrobenzene were evaluated by materials exposure to low concentrations of nitrobenzene vapors. The sorption properties of polystyrene allow the retention of the quencher near the fluorophore, leading to improved detection limits compared with pure fluorophores. Obtaining a porous surface of the polymer material by the Breath Figure technique increases the scale of its fluorescence quenching by vapors. Detection limits (down to 0.45 ppm) and detectable concentration ranges (0.5 - 371.6 ppm) have been experimentally established. The relative standard deviations of the fluorescent signal of polymer materials do not exceed 13.3 % for a number of concentrations in the detectable range. The applicability of the calibration linear relationship of the logarithm of the fluorescent signal on the logarithm of the nitrobenzene vapor concentration is shown. Fluorescence signal measurements were performed using the original sensor element and the luminescence detector employing an array of fluorescent materials. The developed device is simple in application, portable, automated, and in combination with the used polymeric materials allows detection of nitrobenzene vapors in concentrations 2.5 times lower than the maximum permissible level.
{"title":"FLUORESCENT DETECTION OF NITROBENZENE VAPORS VIA FLUOROPHORE-DOPED POLYSTYRENE MATERIALS","authors":"R. Chuvashov, D. Belyaev, K. Khokhlov, A. Baranova, M. Zen Eddin, I. Milman, E. Verbitskiy","doi":"10.15826/analitika.2022.26.4.005","DOIUrl":"https://doi.org/10.15826/analitika.2022.26.4.005","url":null,"abstract":"Integration of fluorescent substances into polymeric matrices can improve their sensory properties and photostability. In this work, fluorescent materials based on fluorophore-doped polystyrene were obtained and characterized as sensors towards the ecotoxicant nitrobenzene in gas phase. Melamine-formaldehyde foam has been proposed as a permeable substrate for the sensor material deposition applicable for gas-phase measurements. The effect on sensor properties of the porous material surface obtained via Breath Figure pore generation technique was investigated. Limits of detection and calibration relationships of obtained materials towards nitrobenzene were evaluated by materials exposure to low concentrations of nitrobenzene vapors. The sorption properties of polystyrene allow the retention of the quencher near the fluorophore, leading to improved detection limits compared with pure fluorophores. Obtaining a porous surface of the polymer material by the Breath Figure technique increases the scale of its fluorescence quenching by vapors. Detection limits (down to 0.45 ppm) and detectable concentration ranges (0.5 - 371.6 ppm) have been experimentally established. The relative standard deviations of the fluorescent signal of polymer materials do not exceed 13.3 % for a number of concentrations in the detectable range. The applicability of the calibration linear relationship of the logarithm of the fluorescent signal on the logarithm of the nitrobenzene vapor concentration is shown. Fluorescence signal measurements were performed using the original sensor element and the luminescence detector employing an array of fluorescent materials. The developed device is simple in application, portable, automated, and in combination with the used polymeric materials allows detection of nitrobenzene vapors in concentrations 2.5 times lower than the maximum permissible level.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67255067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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