A direct enantio-,diastereo-,and chemo-selective high-performance liquid chromatographic method was developed for determining the content,enantiomeric purity,and related substances of the chiral antidepressant drug se...A direct enantio-,diastereo-,and chemo-selective high-performance liquid chromatographic method was developed for determining the content,enantiomeric purity,and related substances of the chiral antidepressant drug sertraline HCl in a single chromatographic run.The separation was achieved on a chiral stationary phase based on amylose tris(3-chloro-5-methylphenylcarbamate)under reversed-phase conditions.The method was optimized by evaluating the influence of the temperature and mobile phase composition on the retention and selectivity.The application of the single-run approach allowed to baseline resolve all investigated species in less than 15 min,without using buffers or tandem-coupled columns.The chromatographic method was validated according to the guidelines of the Official Medicines Control Laboratory and applied to control the content of sertraline HCl and related chiral substances in a generic antidepressant formulation.展开更多
High Performance Liquid Chromatography (HPLC) experiments have been performed on nine steviol glycosides namely rebaudioside A, steviolbioside, stevioside, rubusoside, rebaudioside B, rebaudioside C, rebaudioside D, r...High Performance Liquid Chromatography (HPLC) experiments have been performed on nine steviol glycosides namely rebaudioside A, steviolbioside, stevioside, rubusoside, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside F, and dulcoside A isolated from the leaves of Stevia rebaudiana using Reversed-Phase (RP) column. Using RP-HPLC method, the individual retention times for nine naturally occurring ent-kaurane diterpene glycosides of S. rebaudiana reported in JECFA have been determined at four different temperatures: 20℃, 40℃, 60℃, and 79℃. Also, calculated the relative retention times of the eight steviol glycosides steviolbioside, stevioside, rubusoside, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside F, and dulcoside A against the major steviol glycoside rebaudioside A. HPLC results suggested that temperatures 40℃ and 60℃ would be ideal conditions for better separation of steviol glycosides.展开更多
Objective To develop a simple and specific reversed-phase HPLC-UV method for simultaneous determination of(-)Epigallocatechin-3-gallate(EGCG)and(-)Epicatechin-3-gallate(ECG),the main active ingredients of tea polyphen...Objective To develop a simple and specific reversed-phase HPLC-UV method for simultaneous determination of(-)Epigallocatechin-3-gallate(EGCG)and(-)Epicatechin-3-gallate(ECG),the main active ingredients of tea polyphenols(TP),in rat plasma.Methods EGCG and ECG were eluted on a Kromasil C18 analytical column(150 mm×4.6 mm,5 μm)protected by a C18 pre-column(4.6 mm×20 mm,10 μm)with a linear gradient mobile phase composed of CH3CN(A)-0.1% citric acid(B),which was run from initial 14% A and 86% B to 20% A and 80% B at a flow rate of 1.0 mL·min-1 in 14 min,then changed to 14% A and 86% B at a gradient flow rate of 1.0-1.5 mL·min-1 during 14-18 min,and then maintained until 22 min at a gradient flow rate of 1.5-1.0 mL·min-1.The UV detector was set at 280 nm.Plasma samples(200 μL each)were prepared by liquid-liquid extraction procedure with double volumes of EtoAc and then evaporation of organic phase under N2 stream to dry,followed by reconstitution with 100 μL of 20% CH3CN aqueous solution.The peak area ratios of analytes to vanillin as internal standard vs concentration of analytes to construct calibration curves.Results The HPLC resulted in base-line separation of vanillin,EGCG,ECG and other components;there was no interference from blank plasma.The linear range was 0.5-300 μg·mL-1 for EGCG(r=0.9999)and 0.1-60 μg·mL-1 for ECG(r=0.9999).The intra-and inter-day precision(RSD)was better than 6.1% and 12.6%,respectively,and the average accuracy was between 86.25%-103.14%.The extraction recovery of EGCG and ECG was 79.80%-84.64% and 75.22%-91.39%,respectively.The plasma samples were stable for at least 30 days at-20 ℃ and 8 h at room temperature;EGCG,ECG and IS stock solutions 2 months at-20 ℃,and the EtoAc-extracted plasma samples 24 h at 4 ℃.Application of the method to the determination of EGCG and ECG in plasma of rats receiving iv 100 mg·kg-1 of TP showed that these 2 compounds pharmacokinetically behaved as the two-compartment model and first-order kinetics,with t1/2β 122.9 min and 59.2 min,Vd 7.96 L·kg-1 and 1.22 L·kg-1,CL 0.044 L·kg-1·min-1 and 0.015 L·kg-1·min-1 for EGCG and ECG,respectively.Conclusions The method developed in the present study is highly specific,precise,accurate,and suitable for the non-clinical pharmacokinetic study of the TP in rats.展开更多
The development of facile and rapid quantification of biologically active biomolecules such as isotretitoin in therapeutic drugs contained in many generic formu- lations is necessary for determining their efficiency a...The development of facile and rapid quantification of biologically active biomolecules such as isotretitoin in therapeutic drugs contained in many generic formu- lations is necessary for determining their efficiency and their quality to improve the human health care. Isotretritoin finds its applications in the maintenance of epithelial tissues. Different processes to date such as normal phase HPLC, or gas chromatrography am- ong others are able to separate and quantify isote- troin. However, the extraction is quite complex and in the case of HPLC, the analysis requires long retention times. In such context, an isocratic reversed- phase high-performance liquid chromatography (HP- LC) technique coupled with an UV-vis detector is described here for easy separation and quantification of 13-cis-retinoic (isotretinoin) from soft gelatin capsule formulations. The isotretinoin was extracted from three different commercial drug samples with tetrahydrofuran (THF) solvent by a procedure that can be completed in less than 10 minutes. Subsequent separation and quantification were accomplished in less than 5 minutes under isocratic reversed-phase conditions on a Lichrospher RP18 column and a mobile phase consisting of 0.01% TFA/acetonitrile (15/85, v/v) at a flow rate of 1.0 mL/min. Isotretoin was detected for the three samples via its UV-vis absorbance at 342 nm. The method was validated and the results showed good linearity, precision and accuracy for sensitive and selective quantitative determination of isotretinoin in the different pharmaceutical formulations. We found that the average isotretinoin content in two of the three commercial pro- ducts fell outside the 90-110% United States Pha- rmacopeia specifications. Consequently, the facile extraction and the precise method for the biomole- cule quantification open up tremendous possibilities in improving the quality control of drugs which can exist as different generic brands.展开更多
A rapid, straightforward, sensitive, efficient, and cost-effective reverse-phase high-performance liquid chromatographic method was employed for the simultaneous determination of Sorbitol, Sodium Lactate, and Chloride...A rapid, straightforward, sensitive, efficient, and cost-effective reverse-phase high-performance liquid chromatographic method was employed for the simultaneous determination of Sorbitol, Sodium Lactate, and Chlorides in a drug solution for infusion. Sorbitol, Sodium lactate, and Chloride are all officially recognized in the USP monograph. Assay methods are provided through various techniques, with titrations being ineffective for trace-level quantification. Alternatively, IC, AAS, and ICP-MS, though highly accurate, are costly and often unavailable to most testing facilities. When considering methods, it’s important to prioritize both quality control requirements and user-friendly techniques. A simple HPLC simultaneous method was developed for the quantification of Chlorides, Sorbitol, and Sodium Lactate with a shorter run time. The separation utilized a Shimpack SCR-102(H) ion exclusion analytical column (7.9 mm × 300 mm, 7 μm), with a flow rate of 0.6 mL per min. The column compartment temperature was maintained at 40°C, and the injection volume was set at 10 μL, with detection at 200 nm. All measurements were conducted in a 0.1% solution of phosphoric acid. The analytical curves demonstrated linearity (r > 0.9999) in the concentration range of 0.79 to 3.8 mg per mL for Sodium Lactate (SL), 0.16 to 0.79 mg per mL for Sodium Chloride (SC), and 1.5 to 7.2 mg per mL for Sorbitol. Validation of the developed method followed the guidelines of the International Conference on Harmonization (ICH Q2B) and USP. The method exhibited precision, robustness, accuracy, and selectivity. In accelerated stability testing over 6 months, no significant variations were observed in organoleptic analysis and pH. Consequently, the developed method is deemed suitable for routine quality control analyses, enabling the simultaneous determination of Sodium Lactate, Sodium Chloride, and Sorbitol in pharmaceutical formulations and infusions.展开更多
目的:以牛磺熊去氧胆酸和牛磺鹅去氧胆酸为指标,建立龙泽熊胆胶囊中熊胆粉的含量测定方法。方法:采用高效液相色谱串联蒸发光检测器,色谱柱为ChromCore AQ C 18(4.6 mm×250 mm,5μm),乙腈(A)-5 mmol•L^(-1)醋酸铵溶液(B)为流动相,...目的:以牛磺熊去氧胆酸和牛磺鹅去氧胆酸为指标,建立龙泽熊胆胶囊中熊胆粉的含量测定方法。方法:采用高效液相色谱串联蒸发光检测器,色谱柱为ChromCore AQ C 18(4.6 mm×250 mm,5μm),乙腈(A)-5 mmol•L^(-1)醋酸铵溶液(B)为流动相,梯度洗脱(0~40 min,25%A;40~50 min,25%A→29%A;50~80 min,29%A;80~100 min,29%A→40%A),流速1.0 mL•min^(-1),柱温30℃,ELSD漂移管温度110℃,氮流量2.5L•min^(-1)。结果:牛磺熊去氧胆酸进样量在1.069~9.57μg内、牛磺鹅去氧胆酸进样量在0.74046~7.40464μg内,进样量的对数与峰面积的对数呈良好的线性关系;仪器精密度、重复性、稳定性试验的RSD<2.0%;经低、中、高3个浓度的准确度试验考察,牛磺熊去氧胆酸的回收率为95.2%~97.7%,牛磺鹅去氧胆酸的回收率为91.9%~95.9%。测定样品42批次,牛磺熊去氧胆酸和牛磺鹅去氧胆酸的含量分别为0.18~0.43、0.10~0.44 mg•粒^(-1)。结论:本法适用于龙泽熊胆胶囊中熊胆粉的质量控制,可为完善龙泽熊胆胶囊的质量标准提供科学的依据。展开更多
文摘A direct enantio-,diastereo-,and chemo-selective high-performance liquid chromatographic method was developed for determining the content,enantiomeric purity,and related substances of the chiral antidepressant drug sertraline HCl in a single chromatographic run.The separation was achieved on a chiral stationary phase based on amylose tris(3-chloro-5-methylphenylcarbamate)under reversed-phase conditions.The method was optimized by evaluating the influence of the temperature and mobile phase composition on the retention and selectivity.The application of the single-run approach allowed to baseline resolve all investigated species in less than 15 min,without using buffers or tandem-coupled columns.The chromatographic method was validated according to the guidelines of the Official Medicines Control Laboratory and applied to control the content of sertraline HCl and related chiral substances in a generic antidepressant formulation.
文摘High Performance Liquid Chromatography (HPLC) experiments have been performed on nine steviol glycosides namely rebaudioside A, steviolbioside, stevioside, rubusoside, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside F, and dulcoside A isolated from the leaves of Stevia rebaudiana using Reversed-Phase (RP) column. Using RP-HPLC method, the individual retention times for nine naturally occurring ent-kaurane diterpene glycosides of S. rebaudiana reported in JECFA have been determined at four different temperatures: 20℃, 40℃, 60℃, and 79℃. Also, calculated the relative retention times of the eight steviol glycosides steviolbioside, stevioside, rubusoside, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside F, and dulcoside A against the major steviol glycoside rebaudioside A. HPLC results suggested that temperatures 40℃ and 60℃ would be ideal conditions for better separation of steviol glycosides.
文摘Objective To develop a simple and specific reversed-phase HPLC-UV method for simultaneous determination of(-)Epigallocatechin-3-gallate(EGCG)and(-)Epicatechin-3-gallate(ECG),the main active ingredients of tea polyphenols(TP),in rat plasma.Methods EGCG and ECG were eluted on a Kromasil C18 analytical column(150 mm×4.6 mm,5 μm)protected by a C18 pre-column(4.6 mm×20 mm,10 μm)with a linear gradient mobile phase composed of CH3CN(A)-0.1% citric acid(B),which was run from initial 14% A and 86% B to 20% A and 80% B at a flow rate of 1.0 mL·min-1 in 14 min,then changed to 14% A and 86% B at a gradient flow rate of 1.0-1.5 mL·min-1 during 14-18 min,and then maintained until 22 min at a gradient flow rate of 1.5-1.0 mL·min-1.The UV detector was set at 280 nm.Plasma samples(200 μL each)were prepared by liquid-liquid extraction procedure with double volumes of EtoAc and then evaporation of organic phase under N2 stream to dry,followed by reconstitution with 100 μL of 20% CH3CN aqueous solution.The peak area ratios of analytes to vanillin as internal standard vs concentration of analytes to construct calibration curves.Results The HPLC resulted in base-line separation of vanillin,EGCG,ECG and other components;there was no interference from blank plasma.The linear range was 0.5-300 μg·mL-1 for EGCG(r=0.9999)and 0.1-60 μg·mL-1 for ECG(r=0.9999).The intra-and inter-day precision(RSD)was better than 6.1% and 12.6%,respectively,and the average accuracy was between 86.25%-103.14%.The extraction recovery of EGCG and ECG was 79.80%-84.64% and 75.22%-91.39%,respectively.The plasma samples were stable for at least 30 days at-20 ℃ and 8 h at room temperature;EGCG,ECG and IS stock solutions 2 months at-20 ℃,and the EtoAc-extracted plasma samples 24 h at 4 ℃.Application of the method to the determination of EGCG and ECG in plasma of rats receiving iv 100 mg·kg-1 of TP showed that these 2 compounds pharmacokinetically behaved as the two-compartment model and first-order kinetics,with t1/2β 122.9 min and 59.2 min,Vd 7.96 L·kg-1 and 1.22 L·kg-1,CL 0.044 L·kg-1·min-1 and 0.015 L·kg-1·min-1 for EGCG and ECG,respectively.Conclusions The method developed in the present study is highly specific,precise,accurate,and suitable for the non-clinical pharmacokinetic study of the TP in rats.
文摘The development of facile and rapid quantification of biologically active biomolecules such as isotretitoin in therapeutic drugs contained in many generic formu- lations is necessary for determining their efficiency and their quality to improve the human health care. Isotretritoin finds its applications in the maintenance of epithelial tissues. Different processes to date such as normal phase HPLC, or gas chromatrography am- ong others are able to separate and quantify isote- troin. However, the extraction is quite complex and in the case of HPLC, the analysis requires long retention times. In such context, an isocratic reversed- phase high-performance liquid chromatography (HP- LC) technique coupled with an UV-vis detector is described here for easy separation and quantification of 13-cis-retinoic (isotretinoin) from soft gelatin capsule formulations. The isotretinoin was extracted from three different commercial drug samples with tetrahydrofuran (THF) solvent by a procedure that can be completed in less than 10 minutes. Subsequent separation and quantification were accomplished in less than 5 minutes under isocratic reversed-phase conditions on a Lichrospher RP18 column and a mobile phase consisting of 0.01% TFA/acetonitrile (15/85, v/v) at a flow rate of 1.0 mL/min. Isotretoin was detected for the three samples via its UV-vis absorbance at 342 nm. The method was validated and the results showed good linearity, precision and accuracy for sensitive and selective quantitative determination of isotretinoin in the different pharmaceutical formulations. We found that the average isotretinoin content in two of the three commercial pro- ducts fell outside the 90-110% United States Pha- rmacopeia specifications. Consequently, the facile extraction and the precise method for the biomole- cule quantification open up tremendous possibilities in improving the quality control of drugs which can exist as different generic brands.
文摘A rapid, straightforward, sensitive, efficient, and cost-effective reverse-phase high-performance liquid chromatographic method was employed for the simultaneous determination of Sorbitol, Sodium Lactate, and Chlorides in a drug solution for infusion. Sorbitol, Sodium lactate, and Chloride are all officially recognized in the USP monograph. Assay methods are provided through various techniques, with titrations being ineffective for trace-level quantification. Alternatively, IC, AAS, and ICP-MS, though highly accurate, are costly and often unavailable to most testing facilities. When considering methods, it’s important to prioritize both quality control requirements and user-friendly techniques. A simple HPLC simultaneous method was developed for the quantification of Chlorides, Sorbitol, and Sodium Lactate with a shorter run time. The separation utilized a Shimpack SCR-102(H) ion exclusion analytical column (7.9 mm × 300 mm, 7 μm), with a flow rate of 0.6 mL per min. The column compartment temperature was maintained at 40°C, and the injection volume was set at 10 μL, with detection at 200 nm. All measurements were conducted in a 0.1% solution of phosphoric acid. The analytical curves demonstrated linearity (r > 0.9999) in the concentration range of 0.79 to 3.8 mg per mL for Sodium Lactate (SL), 0.16 to 0.79 mg per mL for Sodium Chloride (SC), and 1.5 to 7.2 mg per mL for Sorbitol. Validation of the developed method followed the guidelines of the International Conference on Harmonization (ICH Q2B) and USP. The method exhibited precision, robustness, accuracy, and selectivity. In accelerated stability testing over 6 months, no significant variations were observed in organoleptic analysis and pH. Consequently, the developed method is deemed suitable for routine quality control analyses, enabling the simultaneous determination of Sodium Lactate, Sodium Chloride, and Sorbitol in pharmaceutical formulations and infusions.
