Pub Date : 2019-12-18DOI: 10.15826/analitika.2019.23.4.011
Т. G. Sorochkina, О. Y. Chernova, О. Y. Troshin, А. Y. Sozin, А. Bulanov, А. А. Ermakov
It is for the first time that the method of gas chromatography was used for the determination of silicon fluoride-chlorides SiСl n F 4-n ( n = 0 ÷ 4) which are the initial, intermediate and final substances while producing silicon tetrachloride from silicon tetrachloride and aluminum chloride (III). The analysis of samples taken during this reaction was carried out using the "Tsvet - 800" gas chromatographer. The samples were injected into the instrument using a vacuum dosing system. To separate the components, a chromatographic column made of molybdenum glass with a length of 5 m and an internal diameter of 3 mm was used. It was filled with a Chromatone N-AW-HMDS (grain size 0.250-0.315 mm) with 15% methylsilicon elastoplastic E-301. The registration of silicon fluoride-chlorides was implemented using a thermal conductivity detector. The identification of SiF 4 and SiCl 4 in the mixture was conducted by comparing the times of holding the chromatographic peaks with the times of holding these individual substances. The times of holding not available for SiClF 3 , SiCl 2 F 2 , SiCl 3 F in the individual states were determined using the dependence of the logarithm of the corrected holding time on their molecular mass. The concentrations of silicon fluoride-chlorides were determined using the internal normalization method. The data were obtained on the changes in the concentrations of these substances during the synthesis of silicon tetrachloride. The confirmation of the correctness of the analysis results was made using the method of varying the size of the sample. Key words: silicon fluoride-chlorides, gas chromatography, identification, calibration factor, correctness (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.011 Т .G. Sorochkina, О .Yu. Chernova, О .Yu. Troshin, А .Yu. Sozin, А .D. Bulanov, А . А . Ermakov G.G. Devyatykh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences, ul. Tropinina 49, Nizhny Novgorod, 603950, Russian Federation
首次采用气相色谱法测定由四氯化硅和氯化铝（III）生产四氯化硅时的初始、中间和最终物质氟化硅氯化物SiСl n F 4-n（n=0÷4）。使用“Tsvet-800”气相色谱仪对反应过程中采集的样品进行分析。使用真空给药系统将样品注入仪器中。为了分离组分，使用长度为5m、内径为3mm的钼玻璃制成的色谱柱。用具有15%甲基硅弹塑性E-301的Chromatone N-AW-HMDS（粒度0.250-0.315 mm）填充。氟化硅氯化物的登记是使用热导率检测器来实现的。混合物中SiF4和SiCl4的鉴定是通过将色谱峰的保持时间与这些单独物质的保持时间进行比较来进行的。SiClF3、SiCl2F2、SiCl3F在各个状态下不可用的保温时间是通过校正保温时间的对数对其分子质量的依赖性来确定的。氟化硅氯化物的浓度是通过内部归一化方法确定的。获得了四氯化硅合成过程中这些物质浓度变化的数据。采用改变样品大小的方法对分析结果的正确性进行了确认。关键词：氟化硅氯化物，气相色谱法，鉴定，校准因子，正确性（俄语）DOI：http://dx.doi.org/10.15826/analitika.2019.23.4.011Т.G.Sorochkina，О.Yu.Chernova，О.Yu.Troshin，А.Yu.Sozin，А.D.Bulanov，А。А。Ermakov G.G.Devyatykh俄罗斯科学院高纯物质化学研究所，ul。Tropinina 49，下诺夫哥罗德，603950，俄罗斯联邦
{"title":"Gas chromatographic determination of silicon fluoride-chlorides SiСlnF4-n (n = 0 ÷ 4) obtained by the reaction of silicon tetrafluoride with aluminum chloride (III)","authors":"Т. G. Sorochkina, О. Y. Chernova, О. Y. Troshin, А. Y. Sozin, А. Bulanov, А. А. Ermakov","doi":"10.15826/analitika.2019.23.4.011","DOIUrl":"https://doi.org/10.15826/analitika.2019.23.4.011","url":null,"abstract":"It is for the first time that the method of gas chromatography was used for the determination of silicon fluoride-chlorides SiСl n F 4-n ( n = 0 ÷ 4) which are the initial, intermediate and final substances while producing silicon tetrachloride from silicon tetrachloride and aluminum chloride (III). The analysis of samples taken during this reaction was carried out using the \"Tsvet - 800\" gas chromatographer. The samples were injected into the instrument using a vacuum dosing system. To separate the components, a chromatographic column made of molybdenum glass with a length of 5 m and an internal diameter of 3 mm was used. It was filled with a Chromatone N-AW-HMDS (grain size 0.250-0.315 mm) with 15% methylsilicon elastoplastic E-301. The registration of silicon fluoride-chlorides was implemented using a thermal conductivity detector. The identification of SiF 4 and SiCl 4 in the mixture was conducted by comparing the times of holding the chromatographic peaks with the times of holding these individual substances. The times of holding not available for SiClF 3 , SiCl 2 F 2 , SiCl 3 F in the individual states were determined using the dependence of the logarithm of the corrected holding time on their molecular mass. The concentrations of silicon fluoride-chlorides were determined using the internal normalization method. The data were obtained on the changes in the concentrations of these substances during the synthesis of silicon tetrachloride. The confirmation of the correctness of the analysis results was made using the method of varying the size of the sample. Key words: silicon fluoride-chlorides, gas chromatography, identification, calibration factor, correctness (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.011 Т .G. Sorochkina, О .Yu. Chernova, О .Yu. Troshin, А .Yu. Sozin, А .D. Bulanov, А . А . Ermakov G.G. Devyatykh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences, ul. Tropinina 49, Nizhny Novgorod, 603950, Russian Federation","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42363234","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.2019.23.4.004
S. M. Leshchev, O. N. Mikhniuk, K. D. Kryzhny, M. Zayats
Using gas chromatography methods with the quadrupole mass spectrometric detector and flame ionization detector, as well as high-performance liquid chromatography with the diode-matrix detector, the distribution constants of codeine, phenobarbital, modafinil, adrafinil, pseudoephedrine for hexane-water, hexane-water systems of inorganic salt solutions (sodium chloride, dipotassium phosphate, potassium carbonate and ammonium sulfate), chloroform-water, chloroform-aqueous solutions of inorganic salts (sodium chloride, dipotassium phosphate, potassium carbonate and ammonium sulfate) were determined. The principal possibility of quantitative extraction of all the investigated substances from the aqueous matrices by salting out was shown. The patterns of salting out of the studied substances from the aqueous solutions were established. In particular, the salting out ability of salts increased sharply with the increasing charge of the salt anion. A significant effect on the salting out effect was exerted by the nature of the extracted compound. It has been shown that the following compounds could be quantitatively recovered in the hexane: codeine, modafinil, and afrafinil. Due to their high hydrophilicity, phenobarbital and pseudoephedrine were not quantitatively extracted with the hexane even at the salt concentration close to the saturation. For the extraction of phenobarbital and pseudoephedrine, the more active but less selective chloroform was used. Based on the obtained values of the distribution constants of the substances and their acid-base properties, the extraction methods for the sample preparation of the various objects were proposed with determining the studied substances in them using salting out. The methodology for the determination of pseudoephedrine and codeine in drugs was tested. It was based on the preliminary removal of the matrix components by chloroform from the aqueous acidic solution and subsequent alkalization, salting out, and extraction with chloroform. The characteristics of the methods were as follows: detection limit for pseudoephedrine - 0.09 g/dm 3 and for codeine - 0.07 g/dm 3 ; standard deviation did not exceed 4% for both substances, range of determined concentrations for all-ephedrine was 0.09 – 3.00 g/dm 3 , and for codeine - 0.07 - 4.00 g/dm 3 respectively. Key words : salting out, chromatography, increment of methylene group, solution structure, Sechenov constant (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.004 S.M. Leshchev 1 , O.N. Mikhniuk 2 , K.D. Kryzhny 2 , M.F. Zayats 1 1 Belarusian State University, ul. Leningradskaya, 14, Minsk, 220050, Republic of Belarus 2 State institute of advanced training and retraining of customs authorities of the Republic of Belarus, ul. Mogilevskaya, 45/4, Minsk, 220007, Republic of Belarus
{"title":"The use of salting out for the extraction of hydrophilic biologically active substances from the aqueous solutions for their further chromatographic determination","authors":"S. M. Leshchev, O. N. Mikhniuk, K. D. Kryzhny, M. Zayats","doi":"10.15826/analitika.2019.23.4.004","DOIUrl":"https://doi.org/10.15826/analitika.2019.23.4.004","url":null,"abstract":"Using gas chromatography methods with the quadrupole mass spectrometric detector and flame ionization detector, as well as high-performance liquid chromatography with the diode-matrix detector, the distribution constants of codeine, phenobarbital, modafinil, adrafinil, pseudoephedrine for hexane-water, hexane-water systems of inorganic salt solutions (sodium chloride, dipotassium phosphate, potassium carbonate and ammonium sulfate), chloroform-water, chloroform-aqueous solutions of inorganic salts (sodium chloride, dipotassium phosphate, potassium carbonate and ammonium sulfate) were determined. The principal possibility of quantitative extraction of all the investigated substances from the aqueous matrices by salting out was shown. The patterns of salting out of the studied substances from the aqueous solutions were established. In particular, the salting out ability of salts increased sharply with the increasing charge of the salt anion. A significant effect on the salting out effect was exerted by the nature of the extracted compound. It has been shown that the following compounds could be quantitatively recovered in the hexane: codeine, modafinil, and afrafinil. Due to their high hydrophilicity, phenobarbital and pseudoephedrine were not quantitatively extracted with the hexane even at the salt concentration close to the saturation. For the extraction of phenobarbital and pseudoephedrine, the more active but less selective chloroform was used. Based on the obtained values of the distribution constants of the substances and their acid-base properties, the extraction methods for the sample preparation of the various objects were proposed with determining the studied substances in them using salting out. The methodology for the determination of pseudoephedrine and codeine in drugs was tested. It was based on the preliminary removal of the matrix components by chloroform from the aqueous acidic solution and subsequent alkalization, salting out, and extraction with chloroform. The characteristics of the methods were as follows: detection limit for pseudoephedrine - 0.09 g/dm 3 and for codeine - 0.07 g/dm 3 ; standard deviation did not exceed 4% for both substances, range of determined concentrations for all-ephedrine was 0.09 – 3.00 g/dm 3 , and for codeine - 0.07 - 4.00 g/dm 3 respectively. Key words : salting out, chromatography, increment of methylene group, solution structure, Sechenov constant (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.004 S.M. Leshchev 1 , O.N. Mikhniuk 2 , K.D. Kryzhny 2 , M.F. Zayats 1 1 Belarusian State University, ul. Leningradskaya, 14, Minsk, 220050, Republic of Belarus 2 State institute of advanced training and retraining of customs authorities of the Republic of Belarus, ul. Mogilevskaya, 45/4, Minsk, 220007, Republic of Belarus","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43903108","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.2019.23.4.008
A. Temerdashev, E. Dmitrieva, A. Azaryan, D. A. Burmikin
Wide dissemination of growth hormone-releasing peptides for professional athletes as well as in amateur sports requires constant attention from the law enforcement agencies. However, in addition to examining the seized materials to establish their active components, it is advisable and necessary to control the growth hormone-releasing peptides in the urine at the trace concentration level since the effective doses of the use of growth hormone-releasing peptides are relatively low and the rate of their excretion from the body often does not allow the determination of native compounds and their metabolites even a few days after the administration. A procedure for the measurement of some growth hormone-releasing peptides in the urine using the ultra-high-performance liquid chromatography (UHPLC) in combination with the high-resolution mass spectrometry (HRMS) has been proposed. It was found that the highest sensitivity could be achieved by utilizing the mobile phase consisting of 0.1% solution of trifluoroacetic acid in water and acetonitrile acidified with trifluoroacetic acid (0.1%). The concentration factor using the solid-phase extraction has been established. As it could be seen from the presented data, the highest extraction efficiency was achieved using the cation-exchange sorbents, while the octadecyl sorbent, in fact, was ineffective in this case. The matrix effects were noted not to exceed 15% during the research. The use of HRMS allows for high sensitivity due to the selectivity of the method. Keywords : UHPLC-HRMS, releasing-peptides, doping, mass-spectrometry (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.008 A.Z. Temerdashev 1 , E.V. Dmitrieva 1 , A.A. Azaryan 1 , D.A. Burmikin 2 1 Kuban State University, Stavropolskaya st., 149, Krasnodar, 350055, Russian Federation 2 Bruker Ltd., Pyatnitskaya st., 50/2, Moscow, 119017, Russian Federation
{"title":"UHPLC-HRMS determination of some human growth hormone-releasing peptides in urine","authors":"A. Temerdashev, E. Dmitrieva, A. Azaryan, D. A. Burmikin","doi":"10.15826/analitika.2019.23.4.008","DOIUrl":"https://doi.org/10.15826/analitika.2019.23.4.008","url":null,"abstract":"Wide dissemination of growth hormone-releasing peptides for professional athletes as well as in amateur sports requires constant attention from the law enforcement agencies. However, in addition to examining the seized materials to establish their active components, it is advisable and necessary to control the growth hormone-releasing peptides in the urine at the trace concentration level since the effective doses of the use of growth hormone-releasing peptides are relatively low and the rate of their excretion from the body often does not allow the determination of native compounds and their metabolites even a few days after the administration. A procedure for the measurement of some growth hormone-releasing peptides in the urine using the ultra-high-performance liquid chromatography (UHPLC) in combination with the high-resolution mass spectrometry (HRMS) has been proposed. It was found that the highest sensitivity could be achieved by utilizing the mobile phase consisting of 0.1% solution of trifluoroacetic acid in water and acetonitrile acidified with trifluoroacetic acid (0.1%). The concentration factor using the solid-phase extraction has been established. As it could be seen from the presented data, the highest extraction efficiency was achieved using the cation-exchange sorbents, while the octadecyl sorbent, in fact, was ineffective in this case. The matrix effects were noted not to exceed 15% during the research. The use of HRMS allows for high sensitivity due to the selectivity of the method. Keywords : UHPLC-HRMS, releasing-peptides, doping, mass-spectrometry (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.008 A.Z. Temerdashev 1 , E.V. Dmitrieva 1 , A.A. Azaryan 1 , D.A. Burmikin 2 1 Kuban State University, Stavropolskaya st., 149, Krasnodar, 350055, Russian Federation 2 Bruker Ltd., Pyatnitskaya st., 50/2, Moscow, 119017, Russian Federation","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48069704","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.2019.23.4.015
O. Melchakova, P. Zaitceva, A. Maiorova, T. Kulikova, N. Pechishcheva, K. Shunyaev
Thermodynamic properties, namely standard molar enthalpy of formation (Δ H f ° 298 ), standard molar entropy ( S ° 298 ), and temperature dependence of heat capacity ( С р ( Т )) of crystalline metal perrhenates, were assessed by the semi-empirical methods. In this work, Δ H f ° 298 , S ° 298 and coefficients a , b and c for C p = а + 0.001× b × T + 10 5 × c × T – 2 equation were calculated using several methods and averaged. These thermodynamic properties were calculated for the following perrhenates metals: Li, N, K, Rb, Cs, Cu, Ba, Fe, Ca, Cd, Co, Mg, Mn, Pb, Sr, Zn, Al, Crи Fe. The calculated values of the thermodynamic properties were in good accordance with the known literature data. New data were applied to the thermodynamic simulation of rhenium-containing sample pretreatment processes for the chemical analysis. The thermodynamic simulation of the sintering sample with the magnesium oxide with/without oxidizing agents was carried out using HSC 6.1 software with new data about the perrhenates. According to the calculated results, the addition of the oxidizing agent (NaNO 3 or K 2 S 2 O 7 ) to the magnesium oxide was needed and its presence ensured the rhenium transition into the solution without losses. In this case, rhenium was present at the temperature of the sintering predominantly as NaReO 4 c or KReO 4 c . Calculation results and estimation of perrhenates thermodynamic properties could be used for the thermodynamic simulation of different processes as well as in analytical chemistry and in metallurgy. Keywords : perrhenates, thermodynamic properties, thermodynamic simulation, sintering, oxidizing agent, rhenium (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.015 O.V. Melchakova 1 , P.V. Zaitceva 1 , A.V. Maiorova 1,2 , T.V. Kulikova 1,2 , N.V. Pechishcheva 1 , K.Yu. Shunyaev 1,2 1 Institute of Metallurgy of the Ural Branch of the Russian academy of Sciences, 101, Amundsen street, Ekaterinburg, 620016, Russian Federation, 2 Ural Federal University named after the first President of Russia B.N. Yeltsin, 19, Mira street, Ekaterinburg, 620002, Russian Federation
{"title":"Thermodynamic properties calculation of perrhenates and their application in the simulation of sample pretreatment for the chemical analysis","authors":"O. Melchakova, P. Zaitceva, A. Maiorova, T. Kulikova, N. Pechishcheva, K. Shunyaev","doi":"10.15826/analitika.2019.23.4.015","DOIUrl":"https://doi.org/10.15826/analitika.2019.23.4.015","url":null,"abstract":"Thermodynamic properties, namely standard molar enthalpy of formation (Δ H f ° 298 ), standard molar entropy ( S ° 298 ), and temperature dependence of heat capacity ( С р ( Т )) of crystalline metal perrhenates, were assessed by the semi-empirical methods. In this work, Δ H f ° 298 , S ° 298 and coefficients a , b and c for C p = а + 0.001× b × T + 10 5 × c × T – 2 equation were calculated using several methods and averaged. These thermodynamic properties were calculated for the following perrhenates metals: Li, N, K, Rb, Cs, Cu, Ba, Fe, Ca, Cd, Co, Mg, Mn, Pb, Sr, Zn, Al, Crи Fe. The calculated values of the thermodynamic properties were in good accordance with the known literature data. New data were applied to the thermodynamic simulation of rhenium-containing sample pretreatment processes for the chemical analysis. The thermodynamic simulation of the sintering sample with the magnesium oxide with/without oxidizing agents was carried out using HSC 6.1 software with new data about the perrhenates. According to the calculated results, the addition of the oxidizing agent (NaNO 3 or K 2 S 2 O 7 ) to the magnesium oxide was needed and its presence ensured the rhenium transition into the solution without losses. In this case, rhenium was present at the temperature of the sintering predominantly as NaReO 4 c or KReO 4 c . Calculation results and estimation of perrhenates thermodynamic properties could be used for the thermodynamic simulation of different processes as well as in analytical chemistry and in metallurgy. Keywords : perrhenates, thermodynamic properties, thermodynamic simulation, sintering, oxidizing agent, rhenium (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.015 O.V. Melchakova 1 , P.V. Zaitceva 1 , A.V. Maiorova 1,2 , T.V. Kulikova 1,2 , N.V. Pechishcheva 1 , K.Yu. Shunyaev 1,2 1 Institute of Metallurgy of the Ural Branch of the Russian academy of Sciences, 101, Amundsen street, Ekaterinburg, 620016, Russian Federation, 2 Ural Federal University named after the first President of Russia B.N. Yeltsin, 19, Mira street, Ekaterinburg, 620002, Russian Federation","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49605260","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 : 2019-01-01DOI: 10.15826/ANALITIKA.2019.23.2.006
I. Maksakova, L. V. Eliseeva, M. Bezruchko, A. Krylov
The task of the selective determination of chlorine dioxide in gas environments, including the emissions from the pulp and paper mills, is relevant and in demand. Current article presents a brief review of the existing methods and procedures for measuring the chlorine dioxide in liquid and gas environments, and identifies the problems in controlling the chlorine dioxide in industrial emissions from the pulp and paper production due to the influence of the related substances: molecular chlorine, hydrochloride, hydrochlorate and sulfur dioxide. measuring of its mass concentration by the capillary electrophoresis. The conditions of sampling, all stages of sample preparation and measurements on the instrument were optimized. Based on the experimental studies, a method for measuring the chlorine dioxide in the industrial emissions in the form of chlorite ion in the range from 0.025 to 0.3 mg/m 3 with an expanded uncertainty of 25 % has been developed. The contributions of the components of uncertainties affecting the measurement result were summarized in the budget of the uncertainties prepared during the metrological certification of the measurement procedure. The developed method is more selective and reliable in comparison to the traditional methods (“wet chemistry”) used for the measuring of the chlorine dioxide in industrial emissions.
{"title":"Selective determination of the chlorine dioxide mass concentration in industrial emissions by the capillary electrophoresis","authors":"I. Maksakova, L. V. Eliseeva, M. Bezruchko, A. Krylov","doi":"10.15826/ANALITIKA.2019.23.2.006","DOIUrl":"https://doi.org/10.15826/ANALITIKA.2019.23.2.006","url":null,"abstract":"The task of the selective determination of chlorine dioxide in gas environments, including the emissions from the pulp and paper mills, is relevant and in demand. Current article presents a brief review of the existing methods and procedures for measuring the chlorine dioxide in liquid and gas environments, and identifies the problems in controlling the chlorine dioxide in industrial emissions from the pulp and paper production due to the influence of the related substances: molecular chlorine, hydrochloride, hydrochlorate and sulfur dioxide. measuring of its mass concentration by the capillary electrophoresis. The conditions of sampling, all stages of sample preparation and measurements on the instrument were optimized. Based on the experimental studies, a method for measuring the chlorine dioxide in the industrial emissions in the form of chlorite ion in the range from 0.025 to 0.3 mg/m 3 with an expanded uncertainty of 25 % has been developed. The contributions of the components of uncertainties affecting the measurement result were summarized in the budget of the uncertainties prepared during the metrological certification of the measurement procedure. The developed method is more selective and reliable in comparison to the traditional methods (“wet chemistry”) used for the measuring of the chlorine dioxide in industrial emissions.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67250218","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 : 2019-01-01DOI: 10.15826/analitika.2019.23.3.007
A. A. Nikolaeva, A. Ivanov, E. Korotkova
Флуориметрический метод предложен для качественного и количественного определения пищевой вкусоароматической добавки хинина в напитках-тониках. Выбор данного метода обусловлен его высокой чувствительностью, селективностью и экспрессностью по сравнению с другими методами. Найдены оптимальные условия флуориметрического определения хинина в напитках: растворитель – 0.01 М серная кислота, длина волны возбуждения 353 нм, длина волны люминесценции 452 нм, параметры строба – задержка сигнала 0.85 мкс, длительность сигнала 21.25 мкс. Для увеличения чувствительности разрабатываемой методики проведены исследования люминесценции хинина и определены квантовые выходы люминесценции хинина в различных концентрациях серной кислоты от 0.005 до 1.000 М. Установлено, что наибольшая интенсивность люминесценции хинина, наибольший квантовый выход и наименьший сигнал фона растворителя наблюдается в 0.01 М H2SO4. Исследовано влияние мешающих компонентов пищевой матрицы на флуориметрическое определение хинина. Установлено, что сахар и лимонная кислота не влияют на люминесцентный сигнал хинина. Рассчитан предел обнаружения хинина, который составил 0.0019 мг/дм3. Для проверки правильности флуориметрической методики проведено сравнение результатов со спектрофотометрической методикой определения хинина в напитках (максимальное поглощение хинина при 347 нм). Результаты, полученные двумя методиками, хорошо согласуются, при этом предел обнаружения флуориметрического метода ниже по сравнению с известными методами. Предложенная методика может быть использована для контроля качества и безопасности безалкогольных напитков. Ключевые слова: хинин, флуориметрия, напитки-тоники, квантовый выход люминесценции, параметры строба.
{"title":"Determination of quinine in soft drinks using the fluorometry method","authors":"A. A. Nikolaeva, A. Ivanov, E. Korotkova","doi":"10.15826/analitika.2019.23.3.007","DOIUrl":"https://doi.org/10.15826/analitika.2019.23.3.007","url":null,"abstract":"Флуориметрический метод предложен для качественного и количественного определения пищевой вкусоароматической добавки хинина в напитках-тониках. Выбор данного метода обусловлен его высокой чувствительностью, селективностью и экспрессностью по сравнению с другими методами. Найдены оптимальные условия флуориметрического определения хинина в напитках: растворитель – 0.01 М серная кислота, длина волны возбуждения 353 нм, длина волны люминесценции 452 нм, параметры строба – задержка сигнала 0.85 мкс, длительность сигнала 21.25 мкс. Для увеличения чувствительности разрабатываемой методики проведены исследования люминесценции хинина и определены квантовые выходы люминесценции хинина в различных концентрациях серной кислоты от 0.005 до 1.000 М. Установлено, что наибольшая интенсивность люминесценции хинина, наибольший квантовый выход и наименьший сигнал фона растворителя наблюдается в 0.01 М H2SO4. Исследовано влияние мешающих компонентов пищевой матрицы на флуориметрическое определение хинина. Установлено, что сахар и лимонная кислота не влияют на люминесцентный сигнал хинина. Рассчитан предел обнаружения хинина, который составил 0.0019 мг/дм3. Для проверки правильности флуориметрической методики проведено сравнение результатов со спектрофотометрической методикой определения хинина в напитках (максимальное поглощение хинина при 347 нм). Результаты, полученные двумя методиками, хорошо согласуются, при этом предел обнаружения флуориметрического метода ниже по сравнению с известными методами. Предложенная методика может быть использована для контроля качества и безопасности безалкогольных напитков. Ключевые слова: хинин, флуориметрия, напитки-тоники, квантовый выход люминесценции, параметры строба.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67250684","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 : 2019-01-01DOI: 10.15826/analitika.2019.23.3.013
I. Zenkevich, D. Olisov, R. Shafigulin, A. Bulanova
Significant discrepancies of literature data on the quercetin ( Q ) water solubility (the variations exceed 5000 times!) at the ambient temperature prompted the elaboration of a new approach on its determination. The new approach is based not on the single measurements, but on the revealing and com paring the two dependencies of solubility. First of them is the dependence of the solubility on pH of water solutions S (Q) = a · рН + b , followed by S (Q) interpolation on рН = 7, which corresponds to the pure water. The second one is the dependence of the solubility on acetonitrile content in acetonit rile-water mixtures, log S (Q) = a · [CH 3 CN] + b , followed by log S (Q) extrapolation on the zero concentration of organic solvent, which corresponds to the pure water as well. The analysis of the solutions was fulfilled using the reversed phase high performance liquid chromatography (RP HPLC). The results obtained independently with various methods correspond well with each other: their joint average value for the few samples was 7.1 ± 1.6 mg L -1 (p S = 4.63). Since the results were obtained for quercetin samples that contained different amounts of crystalline and hydrate water, the final sub-routine of analytical procedure was their extrapolation on the zero-water content in the quercetin samples. The necessity of the preliminary control of both the water content and the organic im pu rities in the samples using elemental and HPLC analysis was discussed. The samples of quercetin, as well as other plant extractive substances, could contain impurities that distort the results of its water solubility.
槲皮素(Q)在环境温度下水溶性的文献数据存在显著差异(差异超过5000倍!)，这促使人们提出了一种新的测定方法。新方法不是基于单一的测量，而是基于揭示和比较溶解度的两个依赖关系。首先是溶解度对水溶液pH值的依赖关系S (Q) = a·рН + b，其次是S (Q)插值到рН = 7，对应纯水。二是乙腈-水混合物中溶解度与乙腈含量的关系，log S (Q) = a·[CH 3 CN] + b，其次是对有机溶剂零浓度的log S (Q)外推，也对应纯水。采用反相高效液相色谱(RP - HPLC)对溶液进行分析。各种方法独立得到的结果吻合良好，少数样品的联合平均值为7.1±1.6 mg L -1 (p S = 4.63)。由于槲皮素样品中含有不同数量的结晶水和水合物，所以分析过程的最后一个子程序是他们对槲皮素样品中零水含量的外推。讨论了采用元素分析和高效液相色谱法对样品中水分和有机杂质进行初步控制的必要性。槲皮素的样品，以及其他植物提取物质，可能含有杂质，扭曲其水溶性的结果。
{"title":"A new approach to the chromatographic determination of quercetin water solubility","authors":"I. Zenkevich, D. Olisov, R. Shafigulin, A. Bulanova","doi":"10.15826/analitika.2019.23.3.013","DOIUrl":"https://doi.org/10.15826/analitika.2019.23.3.013","url":null,"abstract":"Significant discrepancies of literature data on the quercetin ( Q ) water solubility (the variations exceed 5000 times!) at the ambient temperature prompted the elaboration of a new approach on its determination. The new approach is based not on the single measurements, but on the revealing and com paring the two dependencies of solubility. First of them is the dependence of the solubility on pH of water solutions S (Q) = a · рН + b , followed by S (Q) interpolation on рН = 7, which corresponds to the pure water. The second one is the dependence of the solubility on acetonitrile content in acetonit rile-water mixtures, log S (Q) = a · [CH 3 CN] + b , followed by log S (Q) extrapolation on the zero concentration of organic solvent, which corresponds to the pure water as well. The analysis of the solutions was fulfilled using the reversed phase high performance liquid chromatography (RP HPLC). The results obtained independently with various methods correspond well with each other: their joint average value for the few samples was 7.1 ± 1.6 mg L -1 (p S = 4.63). Since the results were obtained for quercetin samples that contained different amounts of crystalline and hydrate water, the final sub-routine of analytical procedure was their extrapolation on the zero-water content in the quercetin samples. The necessity of the preliminary control of both the water content and the organic im pu rities in the samples using elemental and HPLC analysis was discussed. The samples of quercetin, as well as other plant extractive substances, could contain impurities that distort the results of its water solubility.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67251550","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 : 2019-01-01DOI: 10.15826/analitika.2019.23.3.010
L. Kartsova, V. Deev, E. Bessonova, O. Belous, N. Platonova
The conditions for the selective separation of polyphenols and caffeine with reverse-phase high-performance liquid chromatography with diodarray ( RP HPLC-DAD ) and mass-spectrometric detections ( RP HPLC/MS ) were found. Using the developed technique, chromatographic profiles of 29 samples of green tea (including 11 selection ones provided by the All-Russian Research Institute of Floriculture and Subtropical Crops, Sochi) were obtained. Using HPLC/MS, two unknown analytes (catechin gallate and gallocatechin gallate) of the tea samples were identified. Chemometric processing of the characteristic profiles of polyphenols by the principal component analysis ( PCA ) was accomplished. On the scores plot for the first and second principal components, there is a separation of data into two clusters (selection and Greenfield teas) relative to the first principal component ( PC-1 ). Analysis of the PC-1 loadings plot revealed the dominant analytes (gallic acid, gallocatechin, caffeine, epigallocatechin gallate and epicatechin gallate), which determine the differences between green teas samples. PCA-model separately for the profiles only selections teas was built. Analysis of the plot of scores relative to the first two principal components made it possible to detect the dependence of the concentration of polyphenols and caffeine in selections tea leafs on harvest season. A possible correlation has been established between PC-2 and harvest time, but this requires further research.
{"title":"Determination of polyphenol antioxidants in the samples of green tea. The characteristic chromatographic profiles","authors":"L. Kartsova, V. Deev, E. Bessonova, O. Belous, N. Platonova","doi":"10.15826/analitika.2019.23.3.010","DOIUrl":"https://doi.org/10.15826/analitika.2019.23.3.010","url":null,"abstract":"The conditions for the selective separation of polyphenols and caffeine with reverse-phase high-performance liquid chromatography with diodarray ( RP HPLC-DAD ) and mass-spectrometric detections ( RP HPLC/MS ) were found. Using the developed technique, chromatographic profiles of 29 samples of green tea (including 11 selection ones provided by the All-Russian Research Institute of Floriculture and Subtropical Crops, Sochi) were obtained. Using HPLC/MS, two unknown analytes (catechin gallate and gallocatechin gallate) of the tea samples were identified. Chemometric processing of the characteristic profiles of polyphenols by the principal component analysis ( PCA ) was accomplished. On the scores plot for the first and second principal components, there is a separation of data into two clusters (selection and Greenfield teas) relative to the first principal component ( PC-1 ). Analysis of the PC-1 loadings plot revealed the dominant analytes (gallic acid, gallocatechin, caffeine, epigallocatechin gallate and epicatechin gallate), which determine the differences between green teas samples. PCA-model separately for the profiles only selections teas was built. Analysis of the plot of scores relative to the first two principal components made it possible to detect the dependence of the concentration of polyphenols and caffeine in selections tea leafs on harvest season. A possible correlation has been established between PC-2 and harvest time, but this requires further research.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67251637","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 : 2019-01-01DOI: 10.15826/analitika.2019.23.3.012
I. Zenkevich, T. Pushkareva, G. Karakashev
Хроматомасс-спектрометрическая характеристика 12 гомологов ряда триалкилтио фос фатов в режиме ВЭЖХ-МС включала определение их индексов удерживания (RI) и регистрацию масс-спектров с ионизацией электрораспылением при детектировании по ло жительно заряженных ионов. Подтверждена корреляция RI(ВЭЖХ) триалкилтио фос фатов и RI(ГЖХ) их структурных аналогов – триалкилфосфатов. Установлено, что зависимость RI(ВЭЖХ) от молекулярных масс гомологов с высокой точностью может быть аппроксимирована уравнением линейной регрессии, RI = aM + b. Аномалии этой зависимости обусловлены тем, что в ГЖХ разветвления углеродного скелета молекул гомологов существенно влияют на характеристики удерживания, а в ВЭЖХ проявляют ся в незна чи тельной степени. Впервые рассмотрены возможности использования гомологических инкрементов ин дексов удерживания, iRI = RI xDRI(CH2), где х = int(M/14), int – функция, обозна ча ющая целую часть частного от деления моле ку лярного массового числа на 14, эквива лен тная за пи си M = 14x + y, уМ – но мер гомоло гической группы соединения, yМ ≡ M(mod14), DRI(CH2) – инкремент индекса удерживания для гомоло гической раз ности СН2 (в ГЖХ равен 100). Показано, что в ВЭЖХ этот инкремент может принимать другие значения; например в ряду триалкилтиофосфатов более информативна величина DRI(CH2) = 74. Применение концепции iRI наиболее эффективно для выявления соедине ний, масс-спе кт ры которых незначительно отличаются от масс-спектров целевых анали тов. В случае триалкилтиофосфатов это продукты частичного гидролиза таких эфиров – диалкилтио фос фаты (RO)2P(S)-OH, которые не могут быть проанализированы методом ГЖХ из-за наличия активного атома водорода в молекулах. Ключевые слова: Триалкилтиофосфаты, высокоэффективная жидкостная хроматогра фия, масс-спектрометрия с ионизацией электрораспылением, индексы удерживания, го мо логические инкременты индексов удерживания, обнаружение диалкилтиофосфатов в реакционных смесях.
trialquiltio fos fats系列中的12个同源光谱仪特征包括对它们的约束指数(RI)的定义和对高带电离子检索电离的质量谱记录。证实了RI(vh)与RI(fat)的结构相似，即trialky磷酸盐。事实证明，RI(wahc)对同伦分子质素的依赖性可以通过线性回归方程(RI = aM + b)精确地近似。这种依赖性的异常是由于同伦分子的碳分子化对抑制特性产生了重大影响，而在异位分子中则表现为零。第一次考虑使用同调增长量阴dex关押,iRI = RI xDRI (CH2), x = int (M / 14), int是战马茶的目标函数,部分私人祈祷coo核素铜质量数分为14эквив懒为p c M =附属14x + y,聪明但гомол措施гическ小组联合,思绪≡M (mod14) DRI (CH2)增长量保持指数为гомолгическ次身份СН2(ГЖХ等于100)。表明，在wac中，这一语句可能具有不同的含义;例如，trialkykiltio磷酸盐系列提供了更多的信息，DRI(CH2) = 74。使用iRI概念最有效地识别连接，其质量pcp与目标肛门的质量谱略有不同。在三磷酸三磷酸的情况下，这些乙醚的部分水解产物是dialkytio fos (S)-OH，由于分子中存在活性氢原子，不能用hh方法分析。关键词:三磷酸三磷酸，高功能性液态色谱仪，电离质谱仪，控制指数，抑制指数逻辑指数，反应混合物中二磷酸盐检测。
{"title":"Features of trialkyl thiophosphates characterization by the retention indices in HPLC combined with the mass spectrometric data","authors":"I. Zenkevich, T. Pushkareva, G. Karakashev","doi":"10.15826/analitika.2019.23.3.012","DOIUrl":"https://doi.org/10.15826/analitika.2019.23.3.012","url":null,"abstract":"Хроматомасс-спектрометрическая характеристика 12 гомологов ряда триалкилтио фос фатов в режиме ВЭЖХ-МС включала определение их индексов удерживания (RI) и регистрацию масс-спектров с ионизацией электрораспылением при детектировании по ло жительно заряженных ионов. Подтверждена корреляция RI(ВЭЖХ) триалкилтио фос фатов и RI(ГЖХ) их структурных аналогов – триалкилфосфатов. Установлено, что зависимость RI(ВЭЖХ) от молекулярных масс гомологов с высокой точностью может быть аппроксимирована уравнением линейной регрессии, RI = aM + b. Аномалии этой зависимости обусловлены тем, что в ГЖХ разветвления углеродного скелета молекул гомологов существенно влияют на характеристики удерживания, а в ВЭЖХ проявляют ся в незна чи тельной степени. Впервые рассмотрены возможности использования гомологических инкрементов ин дексов удерживания, iRI = RI xDRI(CH2), где х = int(M/14), int – функция, обозна ча ющая целую часть частного от деления моле ку лярного массового числа на 14, эквива лен тная за пи си M = 14x + y, уМ – но мер гомоло гической группы соединения, yМ ≡ M(mod14), DRI(CH2) – инкремент индекса удерживания для гомоло гической раз ности СН2 (в ГЖХ равен 100). Показано, что в ВЭЖХ этот инкремент может принимать другие значения; например в ряду триалкилтиофосфатов более информативна величина DRI(CH2) = 74. Применение концепции iRI наиболее эффективно для выявления соедине ний, масс-спе кт ры которых незначительно отличаются от масс-спектров целевых анали тов. В случае триалкилтиофосфатов это продукты частичного гидролиза таких эфиров – диалкилтио фос фаты (RO)2P(S)-OH, которые не могут быть проанализированы методом ГЖХ из-за наличия активного атома водорода в молекулах. Ключевые слова: Триалкилтиофосфаты, высокоэффективная жидкостная хроматогра фия, масс-спектрометрия с ионизацией электрораспылением, индексы удерживания, го мо логические инкременты индексов удерживания, обнаружение диалкилтиофосфатов в реакционных смесях.","PeriodicalId":37743,"journal":{"name":"Analitika i Kontrol","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67251905","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 : 2019-01-01DOI: 10.15826/ANALITIKA.2019.23.1.007
А. I. Sozin, M. Churbanov, О. Chernova, T. G. Sorochkina, G. Snopatin, I. Skripachev, Iu. А. Lesina
Впервые с использованием метода хромато-масс-спектрометрии исследован молекулярный состав примесей в селене особой чистоты. Концентрат нижекипящих по отношению к селену примесей был получен при его вакуумной дистилляции. Примеси конденсировали и перемораживали из паровой фазы за зоной полной конденсации паров селена. Анализ полученных проб проводили с использованием хромато-масс-спектрометра Agilent 6890/5973N. Их ввод в аналитический прибор осуществляли с помощью вакуумной системы. Для разделения примесей использовали капиллярные адсорбционные колонки GS-GasPro 60 м × 0.32 мм с сорбентом модифицированным силикагелем и с сорбентом политриметилсилилпропином (ПТМСП) 25 м × 0.26 мм, df = 0.25 мкм, позволяющие разделять вещества как с низкими, так и с достаточно высокими температурами кипения. Их совместное применение позволило определять в селене более широкий круг примесей. Идентификацию примесей выполняли по их масс-спектрам. Если масс-спектры определяемых веществ не соответствовали ни одному из библиотечных, то их идентификацию проводили восстановлением состава по фрагментным ионам. Таким образом был расшифрован и описан не найденный в литературных источниках масс-спектр примеси СOSe. В селене идентифицированы примеси постоянных газов, диоксида углерода, углеводородов С2–С6, ароматических углеводородов, карбонилсульфида, сероуглерода, некоторых хлорпроизводных углеводородов, циана, соединений селена, эфиров. Ключевые слова: селен особой чистоты, примеси, масс-спектр, идентификация, хромато-масс-спектрометрический анализ.
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