Pub Date : 2020-01-01DOI: 10.15826/analitika.2020.24.4.003
Z. Temerdashev, T. Chervonnaya, T. N. Musorina, V. Bekhterev
Polycyclic aromatic hydrocarbons (PAHs) are a class of compounds which have been known to be carcinogenic, teratogenic and mutagenic as well as act as pollutants of environmental objects. The determination of PAHs in complex matrices is difficult, and it is very important to use an efficient sample pretreatment technique. A sample preparation technique was developed involving extractive freezing-out and centrifugation of the samples for the determination of polycyclic aromatic hydrocarbons (PAHs) in soils and bottom sediments using gas chromatography – mass spectrometry (GC–MS). Sochi soils (The Imereti Lowlands), turf, sea bottom sediments (Azov Sea, The Temryuk Bay), river bottom sediment (Kurchansky estuary) and Caio Romano (Cuba) island sand were selected as the objects for the research. Soils and bottom sediments which contained no determined PAHs were used as model samples. The conditions of sample preparation have been optimized, and the extraction effects of acetonitrile with water on the PAHs recoveries have been investigated. It was found that for the determination of the compounds consisting from two to four fused aromatic rings such as naphthalene, 2-methylnaphthalene, acenaphthylene, biphenyl, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene and pyrene, the extraction occurred when the extractive mixture contained 15% acetonitrile. The proposed method detection limits of individual compounds ranged from 0.83 to 0.92 µg/kg. The extractive mixture containing 50% acetonitrile was proposed for the determination of 20 PAHs such as naphthalene, 2-methylnaphthalene, acenaphthene, biphenyl, acenaphthylene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, triphenylene, benz[b]fluoranthene, benz[k]fluoranthene, benz[e]pyrene, benz[a]pyrene, indene[1,2,3–c,d]pyrene, dibenz[a,h]anthracene, benz[g,h,i]perylene. The extraction of PAHs in these conditions demonstrated the recoveries from 61% to 97%. As matter of fact, the lower recoveries of PAHs, that contained four or more fused aromatic rings, have been caused by the sorption in the cracks of the solid aqueous phase. The extraction, clear-up of extract and concentration were realized as one step of the sample pretreatment. As a result, the rapid and express technique of the sample preparation with combined GC-MS were proposed for the PAHs determination in soils and bottom sediments. This method’s limits of individual PAHs quantitation ranged from 1 to 5 µg/kg, and these were lower that the maximum permissible concentration.
{"title":"Sample preparation of soils and bottom sediments for gas chromatography–mass spectrometry determination of PAHS","authors":"Z. Temerdashev, T. Chervonnaya, T. N. Musorina, V. Bekhterev","doi":"10.15826/analitika.2020.24.4.003","DOIUrl":"https://doi.org/10.15826/analitika.2020.24.4.003","url":null,"abstract":"Polycyclic aromatic hydrocarbons (PAHs) are a class of compounds which have been known to be carcinogenic, teratogenic and mutagenic as well as act as pollutants of environmental objects. The determination of PAHs in complex matrices is difficult, and it is very important to use an efficient sample pretreatment technique. A sample preparation technique was developed involving extractive freezing-out and centrifugation of the samples for the determination of polycyclic aromatic hydrocarbons (PAHs) in soils and bottom sediments using gas chromatography – mass spectrometry (GC–MS). Sochi soils (The Imereti Lowlands), turf, sea bottom sediments (Azov Sea, The Temryuk Bay), river bottom sediment (Kurchansky estuary) and Caio Romano (Cuba) island sand were selected as the objects for the research. Soils and bottom sediments which contained no determined PAHs were used as model samples. The conditions of sample preparation have been optimized, and the extraction effects of acetonitrile with water on the PAHs recoveries have been investigated. It was found that for the determination of the compounds consisting from two to four fused aromatic rings such as naphthalene, 2-methylnaphthalene, acenaphthylene, biphenyl, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene and pyrene, the extraction occurred when the extractive mixture contained 15% acetonitrile. The proposed method detection limits of individual compounds ranged from 0.83 to 0.92 µg/kg. The extractive mixture containing 50% acetonitrile was proposed for the determination of 20 PAHs such as naphthalene, 2-methylnaphthalene, acenaphthene, biphenyl, acenaphthylene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, triphenylene, benz[b]fluoranthene, benz[k]fluoranthene, benz[e]pyrene, benz[a]pyrene, indene[1,2,3–c,d]pyrene, dibenz[a,h]anthracene, benz[g,h,i]perylene. The extraction of PAHs in these conditions demonstrated the recoveries from 61% to 97%. As matter of fact, the lower recoveries of PAHs, that contained four or more fused aromatic rings, have been caused by the sorption in the cracks of the solid aqueous phase. The extraction, clear-up of extract and concentration were realized as one step of the sample pretreatment. As a result, the rapid and express technique of the sample preparation with combined GC-MS were proposed for the PAHs determination in soils and bottom sediments. This method’s limits of individual PAHs quantitation ranged from 1 to 5 µg/kg, and these were lower that the maximum permissible concentration.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67252979","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 : 2020-01-01DOI: 10.15826/analitika.2020.24.4.006
T. A. Kornilova, A. Derouiche, I. Zenkevich
The confirmation of the correspondence of the detected forms of analytes to their molecular structures seems to be one of the principal problems of analytical chemistry. The previous analysis of the series of drugs by reversed-phase HPLC allowed revealing that the retention regularities of the complex polyfunctional organic compounds containing sulfonamide groups -SO2-N< differ from those of other compounds. It was explained by reversible formation of their hydrate forms. To verify this proposition, three model N-substituted arylsulfonamides were synthesized, namely N,N-diethyl- (I), N-allyl- (II), and N-phenyl (III). The consideration of the dependencies of these analytes net retention times (tR) in reverse-phase HPLC on the content of organic solvent (C, methanol) in an eluent did not permit us to reveal any regularities or anomalies due to the non-linearity of such dependencies. However, to achieve this, the recurrent approximation was recommended, tR(C + DC) = atR(C ) + b (*), where DC = const – constant variations of concentration of methanol (5% in our case), а and b – coefficients calculated by Least Squares Method. If the chemical origin of the analytes at the outlet of the chromatographic column remained the same within concentration range Сmin < С < Сmax, dependencies (*) were linear with correlation coefficients R > 0.999. Yet, if additional chemical transformations of analytes took place, namely reversible formation of hydrates (or variations of their composition) due to the presence of water in an eluent, it led to the deviations of recurrent dependencies (*) from linearity. Three sulfonamides under characterization corresponded to different kinds of such deviations: non-linearity within the whole range Сmin < С < Сmax (amide I), presence of two linear dependencies instead of one (amide II), and linearity within the whole range Сmin < С < Сmax (amide III). First two cases corresponded to the interconversion of anhydrous forms and hydrates, or (less probable) different hydrates, while the latter meant the existence of analyte in the single form (probably hydrate). Thus, the analysis of model compounds confirmed that the presence of the polar functionality -SO2-N< was just the reason of hydrate formation in water solutions.
分析物的检测形态与其分子结构的一致性的确认似乎是分析化学的主要问题之一。通过对该系列药物的反相高效液相色谱分析，发现含有磺胺基团-SO2-N<的复合多功能有机化合物的保留规律与其他化合物不同。这可以用它们的水合物形式的可逆形成来解释。为了验证这一观点，我们合成了三种模型N-取代芳基磺酰胺，即N,N-二乙基- (I)， N-烯丙基- (II)和N-苯基(III)。考虑这些分析物在反相高效液相色谱中的净保留时间(tR)与洗脱液中有机溶剂(C，甲醇)含量的依赖关系，由于这种依赖关系的非线性，我们无法揭示任何规律或异常。然而，为了实现这一目标，推荐使用循环近似，tR(C + DC) = atR(C) + b(*)，其中DC = const -甲醇浓度的恒定变化(在我们的例子中为5%)，和b -通过最小二乘法计算的系数。如果色谱柱出口分析物的化学来源在浓度范围Сmin < С < Сmax内保持不变，则相关关系(*)为线性关系，相关系数为R > 0.999。然而，如果分析物发生了额外的化学转化，即由于淋洗液中存在水而产生的水合物的可逆形成(或其成分的变化)，则会导致循环依赖关系(*)偏离线性。表征下的三种磺胺类化合物对应不同的偏差:整个范围内的非线性Сmin < С < Сmax(酰胺I)，存在两个线性依赖关系而不是一个线性依赖关系(酰胺II)，以及整个范围内的线性Сmin < С < Сmax(酰胺III)。前两种情况对应于无水形式和水合物的相互转换，或者(不太可能)不同的水合物，而后者意味着分析物以单一形式存在(pre - ba - b - ly水合物)。因此，对模型化合物的分析证实了极性官能团-SO2-N<的存在正是水溶液中水合物形成的原因。
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Pub Date : 2020-01-01DOI: 10.15826/analitika.2020.24.2.006
I. Gruzdev, B. Kondratenok, E. I. Lyu-Lyan-Min
are compounds. determination gas chromatography the hydrophilicity and polarity of the analytes. The derivatization must be carried out before the extraction concentration stage, but in most methods of the nitrophenols determination in water this approach is not implemented. The method of determination of mononitrophenols (2-, 3-, and 4-nitrophenols) in water was developed. It involved the nitrophenols bromination directly in the water, bromoderivatives liquid extraction with toluene, silylation by N-tert-Butyldimethylsilyl-N-methyltrifluoroacetamide (MTBSTFA) extract and gas chromatographic determination with the electron-capture detector ( GC-ECD ). The nitrophenols bromination conditions in aqueous solutions were optimized (pH value, bromination duration, bromide-ions concentration). In order to reduce the oxidizing activity of bromine, the nitrophenols bromination was recommended in the presence of bromide anions. The extraction (degree of extraction) and gas chromatographic (retention indices, ECD relative molar responses) properties and nitrophenols bromoderivatives properties were studied. It was shown that the degree of extraction of brominated nitrophenols in the toluene/water system exceeded 80% and the subsequent silylation of the bromoderivatives significantly improved their chromatographic properties. The analytical range of nitrophenols in water was 0.02-10 µg/dm 3 with an error of 10-35 %, the detection limits were 0.05-0.07 μg/dm 3 , the sample volume for analysis was 50 cm 3 , the analysis duration was 90 min.
{"title":"Determination of mononitrophenols in water by gas-chromatography","authors":"I. Gruzdev, B. Kondratenok, E. I. Lyu-Lyan-Min","doi":"10.15826/analitika.2020.24.2.006","DOIUrl":"https://doi.org/10.15826/analitika.2020.24.2.006","url":null,"abstract":"are compounds. determination gas chromatography the hydrophilicity and polarity of the analytes. The derivatization must be carried out before the extraction concentration stage, but in most methods of the nitrophenols determination in water this approach is not implemented. The method of determination of mononitrophenols (2-, 3-, and 4-nitrophenols) in water was developed. It involved the nitrophenols bromination directly in the water, bromoderivatives liquid extraction with toluene, silylation by N-tert-Butyldimethylsilyl-N-methyltrifluoroacetamide (MTBSTFA) extract and gas chromatographic determination with the electron-capture detector ( GC-ECD ). The nitrophenols bromination conditions in aqueous solutions were optimized (pH value, bromination duration, bromide-ions concentration). In order to reduce the oxidizing activity of bromine, the nitrophenols bromination was recommended in the presence of bromide anions. The extraction (degree of extraction) and gas chromatographic (retention indices, ECD relative molar responses) properties and nitrophenols bromoderivatives properties were studied. It was shown that the degree of extraction of brominated nitrophenols in the toluene/water system exceeded 80% and the subsequent silylation of the bromoderivatives significantly improved their chromatographic properties. The analytical range of nitrophenols in water was 0.02-10 µg/dm 3 with an error of 10-35 %, the detection limits were 0.05-0.07 μg/dm 3 , the sample volume for analysis was 50 cm 3 , the analysis duration was 90 min.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67252908","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 : 2020-01-01DOI: 10.15826/analitika.2020.24.1.002
A. A. Dudkina, N. V. Saranchina, T. Volgina, N. Gavrilenko, M. A. Gavrilenko
solid-phase extraction from yoghurts and biokefirs in a transparent polymethylmethacrylate matrix as a solid extractant was studied. The analytical signal was formed due to the accumulation of the dye in the volume of the polymer matrix without violating the transparency, and this corresponded to the wavelength of the maximum absorption of the corresponding dye. The sorption mechanism was based on the protonization of the carbonyl groups of PMM in the acidic media, and, as a result, the optode surface became positively charged. Therefore, the sorption of the R ± form of the E131 dye and the azo dye anions occurred by the positively charged PMM surface. The effectiveness of the proposed approach was shown for the identification and determination of the 2 food-grade synthetic dyes content using the visual and spectrophotometric methods. The optimal conditions for the analysis corresponded to pH <3, the duration of dye extraction into the polymer matrix was 20 min, the range of the detected concentrations was 0.2–40.0 mg / kg with the detection limit of 0.05 mg/kg, and an excess of sweeteners and preservatives did not significantly affect the results of the analysis. The results of the determination of the listed dyes were demonstrated in the current work for the case of individual and group presence of dyes in biokefirs and yogurts. The proposed technique is simple in execution and could be carried out using the standard spectrophotometric equipment. The advantage of the developed method for the determination of artificial dyes in comparison with the method of spectrophotometric determination with liquid extraction is a significant increase in the sensitivity of determination due to the accumulation of analyte, the exclusion of turbidity of an aliquot and the absence of dye loss due to its transition into the supernatant, and then into the solid phase of the matrix.
{"title":"Determination of Е102, Е110, Е124, Е131 synthetic dyes in yogurt using the solid-phase spectrophotometry","authors":"A. A. Dudkina, N. V. Saranchina, T. Volgina, N. Gavrilenko, M. A. Gavrilenko","doi":"10.15826/analitika.2020.24.1.002","DOIUrl":"https://doi.org/10.15826/analitika.2020.24.1.002","url":null,"abstract":"solid-phase extraction from yoghurts and biokefirs in a transparent polymethylmethacrylate matrix as a solid extractant was studied. The analytical signal was formed due to the accumulation of the dye in the volume of the polymer matrix without violating the transparency, and this corresponded to the wavelength of the maximum absorption of the corresponding dye. The sorption mechanism was based on the protonization of the carbonyl groups of PMM in the acidic media, and, as a result, the optode surface became positively charged. Therefore, the sorption of the R ± form of the E131 dye and the azo dye anions occurred by the positively charged PMM surface. The effectiveness of the proposed approach was shown for the identification and determination of the 2 food-grade synthetic dyes content using the visual and spectrophotometric methods. The optimal conditions for the analysis corresponded to pH <3, the duration of dye extraction into the polymer matrix was 20 min, the range of the detected concentrations was 0.2–40.0 mg / kg with the detection limit of 0.05 mg/kg, and an excess of sweeteners and preservatives did not significantly affect the results of the analysis. The results of the determination of the listed dyes were demonstrated in the current work for the case of individual and group presence of dyes in biokefirs and yogurts. The proposed technique is simple in execution and could be carried out using the standard spectrophotometric equipment. The advantage of the developed method for the determination of artificial dyes in comparison with the method of spectrophotometric determination with liquid extraction is a significant increase in the sensitivity of determination due to the accumulation of analyte, the exclusion of turbidity of an aliquot and the absence of dye loss due to its transition into the supernatant, and then into the solid phase of the matrix.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67252066","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 : 2020-01-01DOI: 10.15826/analitika.2020.24.3.001
K. S. Gushchaeva, T. Tsiupko, O. B. Voronova
Проблема контроля подлинности пищевых продуктов является актуальной как с теоретической, так и практической точки зрения. По отношению к идентификации продукции применяются различные подходы, например, поиск веществ-маркеров и методы распознавания образов. Последний рассматривает профили различной природы как единую характеристическую особенность продукта, что позволяет получать классификационную модель объектов. Другой способ сравнения профилей – построение и визуальное сравнение лепестковых диаграмм. Данная работа направлена на изучение электрофоретического профиля черного чая и выявление характеристик, позволяющих классифицировать чай по географическому происхождению, не учитывая технологию его изготовления. Проведена апробация методики определения кофеина, катехина, эпигаллокатехин галлата, эпикатехина и галловой кислоты в экстрактах чая методом мицеллярной электрокинетической хроматографии. Установлен диапазон линейности определения, который для всех изучаемых компонентов составляет 0.5-200 мкг/см3, погрешность определения аналитов не превышает 15 %, стандартное отклонение величины площади пиков на электрофореграмме менее 10 %. Изучение электрофоретических профилей экстрактов черного чая различного происхождения позволило выявить девять характеристических пиков, которые удовлетворительно воспроизводятся, разрешены и присутствуют во всех образцах. Сформирован массив данных на основе площадей характеристических пиков электрофореграмм, зарегистрированных для экстрактов ассамского, цейлонского и «оригинального» краснодарского чая. Для нивелирования влияния разброса значений площадей характеристических пиков проведено их соотнесение друг к другу. Применение к матрице данных, включающей соотношения площадей характеристических пиков, дисперсионного анализа с последующей обработкой его результатов методом главных компонент, позволило установить соотношения, оказывающие наибольшее влияние на отнесение образца к группе чая соответствующего происхождения На основе выбранных соотношений площадей построена графическая модель классификации черного чая по происхождению. Проведена ее проверка и получены удовлетворительные результаты. «Визуальные образы», построенные по медианам соотношений площадей характеристических пиков, наглядно показывают различия в группах образцов чая цейлонского, ассамского и краснодарского происхождения. Ключевые слова: полифенолы, черный чай, МЭКХ, характеристические профили, метод главных компонент.
{"title":"Black tea classification based on its electrophoretic profile","authors":"K. S. Gushchaeva, T. Tsiupko, O. B. Voronova","doi":"10.15826/analitika.2020.24.3.001","DOIUrl":"https://doi.org/10.15826/analitika.2020.24.3.001","url":null,"abstract":"Проблема контроля подлинности пищевых продуктов является актуальной как с теоретической, так и практической точки зрения. По отношению к идентификации продукции применяются различные подходы, например, поиск веществ-маркеров и методы распознавания образов. Последний рассматривает профили различной природы как единую характеристическую особенность продукта, что позволяет получать классификационную модель объектов. Другой способ сравнения профилей – построение и визуальное сравнение лепестковых диаграмм. Данная работа направлена на изучение электрофоретического профиля черного чая и выявление характеристик, позволяющих классифицировать чай по географическому происхождению, не учитывая технологию его изготовления. Проведена апробация методики определения кофеина, катехина, эпигаллокатехин галлата, эпикатехина и галловой кислоты в экстрактах чая методом мицеллярной электрокинетической хроматографии. Установлен диапазон линейности определения, который для всех изучаемых компонентов составляет 0.5-200 мкг/см3, погрешность определения аналитов не превышает 15 %, стандартное отклонение величины площади пиков на электрофореграмме менее 10 %. Изучение электрофоретических профилей экстрактов черного чая различного происхождения позволило выявить девять характеристических пиков, которые удовлетворительно воспроизводятся, разрешены и присутствуют во всех образцах. Сформирован массив данных на основе площадей характеристических пиков электрофореграмм, зарегистрированных для экстрактов ассамского, цейлонского и «оригинального» краснодарского чая. Для нивелирования влияния разброса значений площадей характеристических пиков проведено их соотнесение друг к другу. Применение к матрице данных, включающей соотношения площадей характеристических пиков, дисперсионного анализа с последующей обработкой его результатов методом главных компонент, позволило установить соотношения, оказывающие наибольшее влияние на отнесение образца к группе чая соответствующего происхождения На основе выбранных соотношений площадей построена графическая модель классификации черного чая по происхождению. Проведена ее проверка и получены удовлетворительные результаты. «Визуальные образы», построенные по медианам соотношений площадей характеристических пиков, наглядно показывают различия в группах образцов чая цейлонского, ассамского и краснодарского происхождения. Ключевые слова: полифенолы, черный чай, МЭКХ, характеристические профили, метод главных компонент.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67252739","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 : 2020-01-01DOI: 10.15826/analitika.2020.24.4.005
A. Revenko
X-ray fluorescence analysis (XRF) is widely used when determining the concentrations of elements in various materials in biological research. Current review considers the achievements related to the features of the XRF method. X-ray fluorescence analysis in most cases is a non-destructive method that has proven its potential for measuring the concentrations of elements with a high atomic number Z in organs and tissues in vivo. The main areas of its application in biology and medicine are content determination of basic and toxic elements in plants, samples of bones, teeth, hairs, nails and tissues of vital organs, body fluids such as blood, serum, plasma, saliva, urine, etc. Usually, these studies are part of applied programs that include environmental and metabolic analyses of the population, including the influence of professional factors. The advantages of XRF are also discussed with regards to biological materials. It is noted that the form of the element in the sample practically does not affect the analysis result. In recent years, several new XRF spectrometers models have been designed, where polycapillary lenses and half lenses are used as collimating systems. This is important in the case of in vivo application of X-ray fluorescence determination of certain elements in bones and tissues. The dynamic development is typical for detectors with thermoelectric cooling. Variants of preparation of biological materials for analysis are discussed (grinding, dry or wet ashing, acid decomposition, use of suspensions in the case of XRF with TIR). The results of evaluating the interelement effects for XRF of materials of plant origin, including herbs, spices, apple leaves, birch and tomato leaves, tea, wheat, rye, rice, oatmeal, flax flour, beans, ground, and instant coffee are presented. Examples of the use of XRF in various types of forensic research are considered: poisoning, counterfeiting of drugs and food brands, dental implants, identification of remains. The review presents examples of the participation of Russian X-ray physicists in solving the problems under consideration. The list of references is 400 papers, mainly including the publications of the last 20 years.
{"title":"X-Ray Fluorescence Analysis in Biology and Medicine","authors":"A. Revenko","doi":"10.15826/analitika.2020.24.4.005","DOIUrl":"https://doi.org/10.15826/analitika.2020.24.4.005","url":null,"abstract":"X-ray fluorescence analysis (XRF) is widely used when determining the concentrations of elements in various materials in biological research. Current review considers the achievements related to the features of the XRF method. X-ray fluorescence analysis in most cases is a non-destructive method that has proven its potential for measuring the concentrations of elements with a high atomic number Z in organs and tissues in vivo. The main areas of its application in biology and medicine are content determination of basic and toxic elements in plants, samples of bones, teeth, hairs, nails and tissues of vital organs, body fluids such as blood, serum, plasma, saliva, urine, etc. Usually, these studies are part of applied programs that include environmental and metabolic analyses of the population, including the influence of professional factors. The advantages of XRF are also discussed with regards to biological materials. It is noted that the form of the element in the sample practically does not affect the analysis result. In recent years, several new XRF spectrometers models have been designed, where polycapillary lenses and half lenses are used as collimating systems. This is important in the case of in vivo application of X-ray fluorescence determination of certain elements in bones and tissues. The dynamic development is typical for detectors with thermoelectric cooling. Variants of preparation of biological materials for analysis are discussed (grinding, dry or wet ashing, acid decomposition, use of suspensions in the case of XRF with TIR). The results of evaluating the interelement effects for XRF of materials of plant origin, including herbs, spices, apple leaves, birch and tomato leaves, tea, wheat, rye, rice, oatmeal, flax flour, beans, ground, and instant coffee are presented. Examples of the use of XRF in various types of forensic research are considered: poisoning, counterfeiting of drugs and food brands, dental implants, identification of remains. The review presents examples of the participation of Russian X-ray physicists in solving the problems under consideration. The list of references is 400 papers, mainly including the publications of the last 20 years.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67252701","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 : 2020-01-01DOI: 10.15826/analitika.2020.24.1.007
E. Dorozhko, A. O. Gusar, E. A. Bedareva, G. Slepchenko, M. Trusova, E. Korotkova
The method of carbon containing electrode ( CCE ) modification with tosylated arendiazonium salts ( ADT ) was proposed for the voltammetric ( VA ) determination of caffeine in beverages. The comparison of chemical spontaneous and electrochemical modification approaches was carried out for ADT modified CCE for VA caffeine determination for the first time. A new class of ADT is characterized by high solubility and stability for one month that plays significant role in the process of electrode surface modification. Salts with nitro and carboxy substituents were tested. The optimal conditions for the spontaneous chemical modification of the CCE were selected: ADT modifier with NO 2 substituent, electrode immersion time in the modifier solution for 10 seconds, modifier concentration of 5 mg / dm 3 . ADT deposition on the electrode surface was confirmed by the IR spectroscopy and scanning electron microscopy with the formation of covalent bonds between the carbon atoms of electrode surface and the benzene rings of the modifier. It was shown that the electroactive surface area increases by two times after the modification. Consequently, the technique sensitivity increasing the detection limit of 51 mg / dm 3 and linear range extension from 154 up to 500 mg / dm 3 was observed. While applying the modified electrode, the analysis time was reduced to 15 minutes. Furthermore, the suitability of CCE modified with NO 2 substituent was tested for the analytical purposes. As a result, the caffeine was determined in some tonic and carbonated drinks. The comparison of the results obtained by the proposed method with ADT modified CCE and the level declared by the manufacturer was carried out. The high compliance was established. In addition, the obtained data was consistent with the results by the independent spectrophotometric method.
{"title":"Caffeine determination in beverages by voltammetry with the carbon-containing electrodes modified with aryldiazonium salts","authors":"E. Dorozhko, A. O. Gusar, E. A. Bedareva, G. Slepchenko, M. Trusova, E. Korotkova","doi":"10.15826/analitika.2020.24.1.007","DOIUrl":"https://doi.org/10.15826/analitika.2020.24.1.007","url":null,"abstract":"The method of carbon containing electrode ( CCE ) modification with tosylated arendiazonium salts ( ADT ) was proposed for the voltammetric ( VA ) determination of caffeine in beverages. The comparison of chemical spontaneous and electrochemical modification approaches was carried out for ADT modified CCE for VA caffeine determination for the first time. A new class of ADT is characterized by high solubility and stability for one month that plays significant role in the process of electrode surface modification. Salts with nitro and carboxy substituents were tested. The optimal conditions for the spontaneous chemical modification of the CCE were selected: ADT modifier with NO 2 substituent, electrode immersion time in the modifier solution for 10 seconds, modifier concentration of 5 mg / dm 3 . ADT deposition on the electrode surface was confirmed by the IR spectroscopy and scanning electron microscopy with the formation of covalent bonds between the carbon atoms of electrode surface and the benzene rings of the modifier. It was shown that the electroactive surface area increases by two times after the modification. Consequently, the technique sensitivity increasing the detection limit of 51 mg / dm 3 and linear range extension from 154 up to 500 mg / dm 3 was observed. While applying the modified electrode, the analysis time was reduced to 15 minutes. Furthermore, the suitability of CCE modified with NO 2 substituent was tested for the analytical purposes. As a result, the caffeine was determined in some tonic and carbonated drinks. The comparison of the results obtained by the proposed method with ADT modified CCE and the level declared by the manufacturer was carried out. The high compliance was established. In addition, the obtained data was consistent with the results by the independent spectrophotometric method.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67252267","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 : 2019-12-18DOI: 10.15826/analitika.2019.23.4.013
A. I. Desyatova, N. G. Kovaleva, D. Ponomarev, I. Zenkevich
The restrictions of the commonly used determination algorithm of gas chromatographic retention indices ( RI ) for the volatile impurities identification of ethyl alcohol being eluted prior to the principal constituent on the standard polar stationary phases (polyethylene glycols) are confirmed. The main reason of these restrictions seems to be the interfering n -alkanes С 6 – С 9 reference with the most of impurities. Due to this reason the identification of ethanol impurities to date preferably is based on comparing the profiles of chromatograms of target samples and those of model mixtures. It is shown that RI calculation in similar cases can be based on the data for the non-alkane reference constituents with known RI values that are always contained in the samples, namely acetone (RI 819 ± 6) and methanol (819 ± 6), in combination with the hold-up time value. Just the RI calculation permits us to reveal few groups of difficult to separate constituents as well as to identify some constituents previously not mentioned among ethanol impurities such as formaldehyde diethyl acetal (RI 860 ± 7) and ethyl vinyl ether (667 ± 10). The identification of ethyl vinyl ether is also confirmed by the analysis of the sample enriched with this ether in the result of the treatment of ethanol, containing small amounts of water, by calcium carbide. In addition, the presence of ethyl vinyl ether is suggested in the sample of absolute ethanol prepared according to the known laboratory method by boiling with anhydrous calcium oxide. The evaluation of quantitative content of impurities is fulfilled using the internal standard method with acetone and methanol as standards. Keywords: Ethyl alcohol, impurities, gas chromatographic analysis, identification, vinyl ethyl ether, formaldehyde diethyl acetal (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.013 1 Alena I. Desyatova, 2 Nina G. Kovaleva, 3 Dmitrii A. Ponomarev, 1 Igor G. Zenkevich 1 St. Petersburg State University, Institute for Chemistry, Universitetskii prosp., 26, St. Petersburg 198504, Russian Federation 2 «Ekroskhim», Evpatoriiskii by-str., 7A, St. Petersburg 194044, Russia т Federation 3 St. Petersburg State Forest Technical University, Institutskii by-str., 5, St. Petersburg 194021, Russian Federation
{"title":"Identification features of volatile impurities in ethyl alcohol using gas chromatographic retention indices","authors":"A. I. Desyatova, N. G. Kovaleva, D. Ponomarev, I. Zenkevich","doi":"10.15826/analitika.2019.23.4.013","DOIUrl":"https://doi.org/10.15826/analitika.2019.23.4.013","url":null,"abstract":"The restrictions of the commonly used determination algorithm of gas chromatographic retention indices ( RI ) for the volatile impurities identification of ethyl alcohol being eluted prior to the principal constituent on the standard polar stationary phases (polyethylene glycols) are confirmed. The main reason of these restrictions seems to be the interfering n -alkanes С 6 – С 9 reference with the most of impurities. Due to this reason the identification of ethanol impurities to date preferably is based on comparing the profiles of chromatograms of target samples and those of model mixtures. It is shown that RI calculation in similar cases can be based on the data for the non-alkane reference constituents with known RI values that are always contained in the samples, namely acetone (RI 819 ± 6) and methanol (819 ± 6), in combination with the hold-up time value. Just the RI calculation permits us to reveal few groups of difficult to separate constituents as well as to identify some constituents previously not mentioned among ethanol impurities such as formaldehyde diethyl acetal (RI 860 ± 7) and ethyl vinyl ether (667 ± 10). The identification of ethyl vinyl ether is also confirmed by the analysis of the sample enriched with this ether in the result of the treatment of ethanol, containing small amounts of water, by calcium carbide. In addition, the presence of ethyl vinyl ether is suggested in the sample of absolute ethanol prepared according to the known laboratory method by boiling with anhydrous calcium oxide. The evaluation of quantitative content of impurities is fulfilled using the internal standard method with acetone and methanol as standards. Keywords: Ethyl alcohol, impurities, gas chromatographic analysis, identification, vinyl ethyl ether, formaldehyde diethyl acetal (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.013 1 Alena I. Desyatova, 2 Nina G. Kovaleva, 3 Dmitrii A. Ponomarev, 1 Igor G. Zenkevich 1 St. Petersburg State University, Institute for Chemistry, Universitetskii prosp., 26, St. Petersburg 198504, Russian Federation 2 «Ekroskhim», Evpatoriiskii by-str., 7A, St. Petersburg 194044, Russia т Federation 3 St. Petersburg State Forest Technical University, Institutskii by-str., 5, St. Petersburg 194021, Russian Federation","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49304668","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 : 2019-12-18DOI: 10.15826/analitika.2019.23.4.002
V. I. Deineka, T. G. Burzhynskaya, L. A. Deineka
With the use of the reversed-phase high-performance liquid chromatography (HPLC) with diode-array and mass spectrometric detection, the species composition of xanthophylls of dried red color Lilium pumilum Delile flowers was determined. It was established that this plant was a unique source of capsorubin derivatives. The main components of the carotenoid complex were diesters of all- trans and cis -isomers of capsorubin (about 70 mol %) formed by the saturated fatty acids from capric to stearic with the largest contribution of myristic (~ 36 mol %) and lauric (~ 31 mol %) acids. In addition to diethers in the extracts, monoesters of capsorubin and capsanthin were also found (about 30 % of the peak areas). The possibilities of varying the composition of the mobile phase - acetone and propanol-2 as components with the high eluting capacity and acetonitrile and methanol as components with the lower eluting power - for the separation of diethers and differentiation of derivatives of capsanthin and capsorubin and to prevent the imposition of peaks of two series homologues were considered. The features of ion formation during the mass spectrometric detection in the mode of chemical ionization at the atmospheric pressure (APCI) were determined. The possibility of using the parameters of capsorubin diester retention to determine the thermodynamically substantiated dead time of the column was considered. Key words : capsorubin, capsanthin, esters, Lilium pumilum Delile, RP-HPLC, APCI, separation selectivity (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.002 V.I. Deineka, T.G. Burzhynskaya, L.A. Deineka Belgorod State National Research University, Russian Federation, 308015, Belgorod, ul. Pobedy, 85
{"title":"Lilium pumilum l petal xanthophylls identification problems by the reversed-phase HPLC method with spectrophotometric and mass-spectrometric detections","authors":"V. I. Deineka, T. G. Burzhynskaya, L. A. Deineka","doi":"10.15826/analitika.2019.23.4.002","DOIUrl":"https://doi.org/10.15826/analitika.2019.23.4.002","url":null,"abstract":"With the use of the reversed-phase high-performance liquid chromatography (HPLC) with diode-array and mass spectrometric detection, the species composition of xanthophylls of dried red color Lilium pumilum Delile flowers was determined. It was established that this plant was a unique source of capsorubin derivatives. The main components of the carotenoid complex were diesters of all- trans and cis -isomers of capsorubin (about 70 mol %) formed by the saturated fatty acids from capric to stearic with the largest contribution of myristic (~ 36 mol %) and lauric (~ 31 mol %) acids. In addition to diethers in the extracts, monoesters of capsorubin and capsanthin were also found (about 30 % of the peak areas). The possibilities of varying the composition of the mobile phase - acetone and propanol-2 as components with the high eluting capacity and acetonitrile and methanol as components with the lower eluting power - for the separation of diethers and differentiation of derivatives of capsanthin and capsorubin and to prevent the imposition of peaks of two series homologues were considered. The features of ion formation during the mass spectrometric detection in the mode of chemical ionization at the atmospheric pressure (APCI) were determined. The possibility of using the parameters of capsorubin diester retention to determine the thermodynamically substantiated dead time of the column was considered. Key words : capsorubin, capsanthin, esters, Lilium pumilum Delile, RP-HPLC, APCI, separation selectivity (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.002 V.I. Deineka, T.G. Burzhynskaya, L.A. Deineka Belgorod State National Research University, Russian Federation, 308015, Belgorod, ul. Pobedy, 85","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47382854","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 : 2019-12-18DOI: 10.15826/analitika.2019.23.4.014
T. Kuchmenko, A. Shuba, R. Umarkhanov, A. E. Chernitskii, Quality Therapy
In this article the “electronic nose” system (SNT LLC, Russia) with an array of 8 differently selective piezoelectric sensors (nanobio array) was used to assess the health and functioning of the respiratory organs in young cattle by the fraction of volatile compounds over bioassays (exhaled breath condensate and nasal mucus). The sorption of the volatile fraction of substances vapors from the two types of bioassays was studied for 80s with the frontal effortless injection of vapors into the near-sensor space of the detection cell of the “electronic nose” at 20 ± 1 oC with the subsequent fixation of the spontaneous desorption for 120s - total measurement time 200s . The simplest analytical signals of the "electronic nose" ( S S и S neg ) recorded and calculated in the software for the samples were proposed suitable for assessing the health of the respiratory organs in calves. A significant correlation was found between the analytical signals of the “electronic nose” and the established informative indicators of bovine respiratory diseases: increased activity of aspartate aminotransferase, alanine aminotransferase, creatinine in samples of exhaled breath condensate, respiratory failure index, and leukocyte count. The samples of nasal mucus were better used for the health assessment of the respiratory system using the nanobio array of sensors. Despite the initial small number of samples, the approach is universal and could be extended to the studies of other animals. Key words : piezosensors, “electronic nose”, correlation coefficient, nasal mucus, exhaled breath condensate, diagnosis, bovine respiratory disease, markers of inflammation (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.014 T.A. Kuchmenko, A.A. Shuba 1 , R.U. Umarkhanov 1 , A.E. Chernitskii 2 1 Voronezh State University of Engineering Technologies”, pr. Revolutsii, 19, Voronezh, 394000, Russian Federation 2 All-Russian Scientific Research Veterinary Institute of Pathology, Pharmacology and Therapy, Research Center of Clinical Pharmacology and Therapy, Quality and Safety of Raw Materials and Products, st. Lomonosova, 114b, Voronezh, Russian Federation
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