The present study analyzed the volatile compounds of three mango varieties (Tommy Atkins, Rosa and Espada) using the static headspace technique with SPME coupled to CG-MS. Multivariate methodologies, such as factorial...The present study analyzed the volatile compounds of three mango varieties (Tommy Atkins, Rosa and Espada) using the static headspace technique with SPME coupled to CG-MS. Multivariate methodologies, such as factorial design and response surface methodology, were used to optimize the conditions of adsorption and desorption of these substances. The data were evaluated by using principal components analysis (PCA) and hierarchical grouping analysis, in order to visualize grouping tendencies of volatile compounds. Thirty-seven volatile compounds belonging to different chemical classes, such as esters, terpenes, alcohols and others, were tentatively identified in the three varieties of mango. Amongst them, twenty-three presented chromatographic peaks with relative areas larger than 2%. The multivariate analysis made it possible to visualize the grouping tendencies of the mango samples, according to the presence of their respective volatile substances, and enabled the identification of the groups of substances responsible for the discrimination among the three varieties.展开更多
Two highly sensitive methods for the determination of genotoxic alkyl methane sulfonates (AMSs) and alkyl paratoluene sulfonates (APTSs) in lamivudine using hyphenated techniques have been presented. AMSs were determi...Two highly sensitive methods for the determination of genotoxic alkyl methane sulfonates (AMSs) and alkyl paratoluene sulfonates (APTSs) in lamivudine using hyphenated techniques have been presented. AMSs were determined by GC-MS method using GSBPINOWAX (30 m 0.25 mm 0.25 mm) column. Temperature program was set by maintaining at 100 1C initially for 3 min, then rised to 220 1C at the rate of 15 1C/min and maintained at 220 1C for 16 min. N,N-dimethyl formamide was used as diluent. APTSs were determined by LC-MS using Zorbax, Rx C8, 250 mm 4.6 mm, 5 mm column as stationary phase. 0.01 M ammonium acetate is used as buffer. The mixture of buffer and methanol in 75:25 (v/v) ratio was used as mobile phase A and mixture of buffer and methanol in 5:95 (v/v) ratio was used as mobile phase B. The gradient program (T/%B) was set as 0/28, 16/50, 17/100, 23/100, 27/28 and 40/28. Both the methods were validated as per International Conference on Harmonization guidelines. Limit of quantitation was found 1.5 mg/mL for AMSs and was in the range of 1.0-1.5 mg/mL for APTSs.展开更多
Drugs are traditionally been identified on basis of chromatographic-spectroscopic hyphenated techniques in instrumental analysis. Gas chromatography (GC) and Liquid chromatography (LC) hyphenated with mass spectroscop...Drugs are traditionally been identified on basis of chromatographic-spectroscopic hyphenated techniques in instrumental analysis. Gas chromatography (GC) and Liquid chromatography (LC) hyphenated with mass spectroscopy (MS) i.e. GC-MS and LC-MS give reliable and confirmatory results in drugs identification. In the present work the novel hyphenated technique High Performance Thin Layer Chromatography-Mass Spectroscopy (HPTLC-MS) has been used. This technique provides efficient, quick and simple method for identification and separation of Narcotic drugs and psychotropic substances. The drugs under study are Papaverine, Methadone, Cocaine, Ketamine, Caffeine, Codeine, Diazepam, Thebaine, Heroin, Methamphetamine, Carbamazepine, Morphine, Narcotine and Ephedrine. The present study comprising of sixteen drugs has been carried out on CAMAG HPTLC instrument with automatic sampling. Thin layer chromatography (TLC) plates were developed in various solvent systems, scanned under TLC scanner and the results in terms of Retention Factor (Rf value) and UV spectrum (λmax) are presented in the manuscript. Using hyphenated technique of HPTLC-MS (MS 2020 SHIMADZU) spots of these drugs from TLC plate was lifted with CAMAG TLC-MS interface and confirmed by the mass spectrum of the individual drugs by their m/z values thus delivering fast and accurate confirmatory result on the TLC plate.展开更多
文摘The present study analyzed the volatile compounds of three mango varieties (Tommy Atkins, Rosa and Espada) using the static headspace technique with SPME coupled to CG-MS. Multivariate methodologies, such as factorial design and response surface methodology, were used to optimize the conditions of adsorption and desorption of these substances. The data were evaluated by using principal components analysis (PCA) and hierarchical grouping analysis, in order to visualize grouping tendencies of volatile compounds. Thirty-seven volatile compounds belonging to different chemical classes, such as esters, terpenes, alcohols and others, were tentatively identified in the three varieties of mango. Amongst them, twenty-three presented chromatographic peaks with relative areas larger than 2%. The multivariate analysis made it possible to visualize the grouping tendencies of the mango samples, according to the presence of their respective volatile substances, and enabled the identification of the groups of substances responsible for the discrimination among the three varieties.
文摘Two highly sensitive methods for the determination of genotoxic alkyl methane sulfonates (AMSs) and alkyl paratoluene sulfonates (APTSs) in lamivudine using hyphenated techniques have been presented. AMSs were determined by GC-MS method using GSBPINOWAX (30 m 0.25 mm 0.25 mm) column. Temperature program was set by maintaining at 100 1C initially for 3 min, then rised to 220 1C at the rate of 15 1C/min and maintained at 220 1C for 16 min. N,N-dimethyl formamide was used as diluent. APTSs were determined by LC-MS using Zorbax, Rx C8, 250 mm 4.6 mm, 5 mm column as stationary phase. 0.01 M ammonium acetate is used as buffer. The mixture of buffer and methanol in 75:25 (v/v) ratio was used as mobile phase A and mixture of buffer and methanol in 5:95 (v/v) ratio was used as mobile phase B. The gradient program (T/%B) was set as 0/28, 16/50, 17/100, 23/100, 27/28 and 40/28. Both the methods were validated as per International Conference on Harmonization guidelines. Limit of quantitation was found 1.5 mg/mL for AMSs and was in the range of 1.0-1.5 mg/mL for APTSs.
文摘Drugs are traditionally been identified on basis of chromatographic-spectroscopic hyphenated techniques in instrumental analysis. Gas chromatography (GC) and Liquid chromatography (LC) hyphenated with mass spectroscopy (MS) i.e. GC-MS and LC-MS give reliable and confirmatory results in drugs identification. In the present work the novel hyphenated technique High Performance Thin Layer Chromatography-Mass Spectroscopy (HPTLC-MS) has been used. This technique provides efficient, quick and simple method for identification and separation of Narcotic drugs and psychotropic substances. The drugs under study are Papaverine, Methadone, Cocaine, Ketamine, Caffeine, Codeine, Diazepam, Thebaine, Heroin, Methamphetamine, Carbamazepine, Morphine, Narcotine and Ephedrine. The present study comprising of sixteen drugs has been carried out on CAMAG HPTLC instrument with automatic sampling. Thin layer chromatography (TLC) plates were developed in various solvent systems, scanned under TLC scanner and the results in terms of Retention Factor (Rf value) and UV spectrum (λmax) are presented in the manuscript. Using hyphenated technique of HPTLC-MS (MS 2020 SHIMADZU) spots of these drugs from TLC plate was lifted with CAMAG TLC-MS interface and confirmed by the mass spectrum of the individual drugs by their m/z values thus delivering fast and accurate confirmatory result on the TLC plate.
