Highly sensitive spectrofluorimetric method was developed and validated for the determination of gabapentin in pure and pharmaceutical preparations. The method was based on nucleophilic substitution reaction of gabape...Highly sensitive spectrofluorimetric method was developed and validated for the determination of gabapentin in pure and pharmaceutical preparations. The method was based on nucleophilic substitution reaction of gabapentin with 4-fluoro-7-nitrobenzofurazan (NBD-F) in an alkaline medium (pH 9.5) to form a highly fluorescent derivative that was measured at 521 nm after excitation at 458 rim. The factors affecting the reaction was carefully studied and optimized. The method was successfully validated for linearity, limit of detection, limit of quantification, accuracy, precision, robustness and specificity. Under the optimized conditions, linear relationship with good correlation coefficient (0.9998) was found between the relative fluorescence intensity and gabapentin concentration in the range of 10--100 ng·mL^-1. The limit of detection and limit of quantification were 0.43 and 1.30 ng·mL ^-1, respectively. The proposed method was successfully applied to the determination of gabapentin in its pharmaceutical capsules. The results obtained by the proposed method were comparable with those obtained by the official method. Statistical comparison by t- and F- tests revealed that there was no significant difference between the results of the two methods with respect to mean values and standard deviations at the 95% confidence level.展开更多
Objective To evaluate the difference between Baishao(Paeoniae Radix Alba,PRA)and Chishao(Paeoniae Radix Rubra,PRR)from different regions based on the characteristic spectra of amino acids(AAs).Methods Fingerprints of ...Objective To evaluate the difference between Baishao(Paeoniae Radix Alba,PRA)and Chishao(Paeoniae Radix Rubra,PRR)from different regions based on the characteristic spectra of amino acids(AAs).Methods Fingerprints of the 21 standard AAs were established using O-phthalaldehyde-9-fluorenylmethyl chloroformate(OPA-FMOC)pre-column derivation method.The AA components in PRA and PRR were characterized qualitatively and quantitatively,and different AAs were screened using pattern recognition technology.Results Twelve AAs were identified in both PRA and PRR.Meanwhile,aspartic acid,glutamic acid,arginine,alanine,and gamma-aminobutyric acid were screened as characteristic components,and their concentrations could effectively distinguish PRA from PRR.Conclusion The established characterization method,which is based on the characteristic spectra of AAs,is accurate,efficient,and sensitive and can effectively distinguish between PRA and PRR from different producing areas,thus providing a reference for the overall characterization and evaluation of Chinese medicinal materials.展开更多
文摘目的基于液相色谱-串联质谱法,建立衍生化法测定乳粉中氟乙酸钠(1080)的新方法。方法样品经水-丙酮提取,阴离子树脂净化后,由3-硝基苯胺-EDAC衍生和HLB净化处理提取,通过BEH C18色谱柱进行分离,电喷雾负离子多反应监测模式进行检测,内标法定量。结果氟乙酸钠(1080)在1.0~100.0ng/mL浓度范围内具有良好的线性,相关系数r为0.9993,检出限(limit of detection, LOD)可达到0.3μg/kg,不同添加浓度的平均回收率在99.1%~103%之间,测定结果的相对标准偏差在2.0%~6.2%之间。结论本方法准确、灵敏度高,可用于乳粉中氟乙酸钠的快速准确测定和定量分析。
文摘Highly sensitive spectrofluorimetric method was developed and validated for the determination of gabapentin in pure and pharmaceutical preparations. The method was based on nucleophilic substitution reaction of gabapentin with 4-fluoro-7-nitrobenzofurazan (NBD-F) in an alkaline medium (pH 9.5) to form a highly fluorescent derivative that was measured at 521 nm after excitation at 458 rim. The factors affecting the reaction was carefully studied and optimized. The method was successfully validated for linearity, limit of detection, limit of quantification, accuracy, precision, robustness and specificity. Under the optimized conditions, linear relationship with good correlation coefficient (0.9998) was found between the relative fluorescence intensity and gabapentin concentration in the range of 10--100 ng·mL^-1. The limit of detection and limit of quantification were 0.43 and 1.30 ng·mL ^-1, respectively. The proposed method was successfully applied to the determination of gabapentin in its pharmaceutical capsules. The results obtained by the proposed method were comparable with those obtained by the official method. Statistical comparison by t- and F- tests revealed that there was no significant difference between the results of the two methods with respect to mean values and standard deviations at the 95% confidence level.
基金We thank for the funding support from the Guangdong Provincial Key Laboratory of Chinese Medicine for Prevention and Treatment of Refractory Chronic Diseases(No.2018B030322012).
文摘Objective To evaluate the difference between Baishao(Paeoniae Radix Alba,PRA)and Chishao(Paeoniae Radix Rubra,PRR)from different regions based on the characteristic spectra of amino acids(AAs).Methods Fingerprints of the 21 standard AAs were established using O-phthalaldehyde-9-fluorenylmethyl chloroformate(OPA-FMOC)pre-column derivation method.The AA components in PRA and PRR were characterized qualitatively and quantitatively,and different AAs were screened using pattern recognition technology.Results Twelve AAs were identified in both PRA and PRR.Meanwhile,aspartic acid,glutamic acid,arginine,alanine,and gamma-aminobutyric acid were screened as characteristic components,and their concentrations could effectively distinguish PRA from PRR.Conclusion The established characterization method,which is based on the characteristic spectra of AAs,is accurate,efficient,and sensitive and can effectively distinguish between PRA and PRR from different producing areas,thus providing a reference for the overall characterization and evaluation of Chinese medicinal materials.