HPTLC Method for Determination of 20-Hydroxyecdysone in Sida rhombifolia L. and Dietary Supplements

Naturally occurring 20-hydroxyecdysone is an important anabolic ecdysteroid. A simple thin-layer chromatography method to quantitate 20-hydroxyecdysone in methanolic extract of the whole plant material of Sida rhombifolia L. was developed. This method was successfully applied for quantitative evaluation of dietary supplements. The separation was achieved on glass TLC plates coated with silica gel 60F254, using chloroform: methanol (8:2 v/v) as developing solvent. Densitometric evaluation of 20-hydroxyecdysone was performed at 250 nm in reflectance/absorbance mode. The calibration was in the range of 200–1,000 ng spot^?1 and correlation coefficient for the calibration curve was >0.999. In addition, for six different Sida species unique fingerprints were obtained on the HPTLC plate.     

A Rapid HPTLC Method for Standardization of Ficus bengalensis Linn.

JPC – Journal of Planar Chromatography – Modern TLC - Because of the increasing importance of Ficus bengalensis as a potent antidiabetic herbal drug, detailed chemical and analytical...     

HPTLC Method for Analysis of Piperine in Fruits of Piper Species

JPC – Journal of Planar Chromatography – Modern TLC - Piperine, an alkaloid with diverse biological activity commonly occurring in fruits of Piper sp., has high commercial, economical,...     

A Validated Stability-Indicating HPTLC Method for the Estimation of Gemcitabine HCI in its Dosage Form

JPC – Journal of Planar Chromatography – Modern TLC - Gemcitabine belongs to a class of drugs known as antimetabolites (pyrimidine analog) used in various carcinomas, such as pancreatic...     

A Simple,Rapid, and Sensitive HPTLC Method for the Estimation of Clarithromycin: Application to Single Dose Clinical Study

JPC – Journal of Planar Chromatography – Modern TLC - Clarithromycin used for the treatment of respiratory tract infection. Anew alternative simple, rapid, sensitive, and selective...     

Stability-Indicating HPTLC Method for Simultaneous Estimation of Amlodipine Besylate,Hydrochlorothiazide and Olmesartan Medoxomil in Combined Tablet Dosage Forms

JPC – Journal of Planar Chromatography – Modern TLC -     

Densitometric HPTLC Method for Qualitative and Quantitative Analysis of Piperitone

JPC – Journal of Planar Chromatography – Modern TLC -     

Stability-Indicating HPTLC Method for Simultaneous Determination of Ezetimibe and Simvastatin

Simvastatin and ezetimibe are used to treat hyperlipidemia. A simple, selective and stability-indicating HPTLC method has been established for analysis of simvastatin and ezetimibe. The method has been validated so that both drugs can routinely be analyzed simultaneously. The method uses aluminum-backed silica gel 60F₂₅₄ TLC plates as stationary phase with n-hexane–acetone 6:4 (v/v) as mobile phase. Densitometric analysis of both drugs was carried out in absorbance mode at 234 nm. This system was found to give compact bands for simvastatin and ezetimibe (R _F 0.39 ± 0.05 and 0.50 ± 0.05, respectively). Linear relationships were obtained between response and amount of drug in the range 200–1,600 ng per band with high correlation coefficients (r ² = 0.9917 ± 0.0018 for simvastatin and r ² = 0.9927 ± 0.0021 for ezetimibe). The method was validated for precision, robustness, and recovery. The limits of detection and quantitation were 25 and 150 ng per band, respectively. Simvastatin and ezetimibe were subjected degradation by acid, pH 6.8 phosphate buffer, oxidation, dry heat, and wet heat. The degradation products were well resolved from the pure drug with significantly different R _F values. Because the method could effectively separate the drug from its degradation products, it can be used for stability-indicating analysis.     

区分麻黄碱立体异构体的质谱新方法

麻黄碱与其异构体——伪麻黄碱具有不同的药理活性,并且麻黄碱作为合成冰毒(苯丙胺)的主要原料,是法庭严格查禁的毒品之一.在实际工作中,经常需要将两者区分开.作者首次利用电喷雾质谱的源内碰撞诱导解离技术,实现了将两者区分开的目的,并利用该方法对一可疑样品进行了检测,证实为麻黄碱.     

HPTLC Determination of Swertiamarin and Amarogentin in Swertia Species from the Western Himalayas

JPC – Journal of Planar Chromatography – Modern TLC - A high-performance thin-layer chromatographic (HPTLC) method has been established for simple and rapid quantification of two...     

表面化学分析与标准化

对表面化学分析标准化作了概述. 介绍了标准管理机构和标准制订程序. 还介绍了表面化学分析的相关标准和标准应用实例.     

HPTLC Method for Determination of Colchicine in a Pharmaceutical Formulation

JPC – Journal of Planar Chromatography – Modern TLC - An HPTLC method, using an internal standard, for analysis of colchicine in a pharmaceutical formulation, has been established and...     

A Validated,Stability-Indicating HPTLC Method for Analysis of Doxofylline

JPC – Journal of Planar Chromatography – Modern TLC - A simple, sensitive, selective, precise, and stability-indicating high-performance thin-layer chromatographic method for analysis...     

Stability-Indicating HPTLC Method for Analysis of Moclobemide, and Use of the Method to Study Degradation Kinetics

A sensitive, selective, precise, and stability-indicating HPTLC method for analysis of moclobemide in the bulk drug and in formulations has been established and validated. Aluminium TLC plates precoated with silica gel 60 F₂₅₄ were used with benzene–methanol–40% ammonia 7:3:0.1 (v/v) as mobile phase. Densitometric analysis was performed in absorbance mode at 238 nm. Compact bands were obtained for moclobemide (R _F 0.67 ± 0.02; n = 6). The drug was subjected to acidic and alkaline hydrolysis, oxidation, dry heat treatment, and photodegradation. The drug undergoes degradation under acidic, basic, and oxidising conditions. The degradation products were well resolved from the pure drug with significantly different R _F values, so the method can be regarded as stability-indicating. Response to moclobemide was a linear function of amount in the range 50–600 ng per band, with a correlation coefficient, r ², of 0.9967 ± 0.51. LOD and LOQ, determined experimentally, were 10 and 30 ng per band, respectively. Statistical analysis proves the method is repeatable and specific for analysis of moclobemide. The method was used to investigate the kinetics of alkaline degradation. The Arrhenius plot was constructed and the activation energy calculated.     

Stability-Indicating HPTLC Method for the Determination of Tamsulosin in Pharmaceutical Dosage Forms

A simple, sensitive, selective, precise and stability indicating high-performance thin-layer chromatographic method was developed for the determination of tamsulosin (TAM) in bulk and tablet formulation. Validation was carried out in compliance with International Conference on Harmonization guidelines. The method employed thin-layer chromatography aluminium plates pre-coated with silica gel 60F₂₅₄ as the stationary phase and the mobile phase consisted of acetonitrile/methanol/dichloromethane (2.0: 1.0: 2.0, v/v/v). This solvent system was found to give compact spots for tamsulosin (R _f = 0.27 ± 0.02). Densitometric analysis of TAM was carried out in the absorbance mode at 286 nm. Linear regression analysis showed good linearity (r ² = 0.9993) with respect to peak area in the concentration range of 300–800 ng per band. The method was validated for precision, accuracy, ruggedness and recovery. Limits of detection and quantitation were 8.49 and 25.72 ng per band, respectively. TAM was subjected to acid and alkali hydrolysis, oxidation, photo degradation, dry heat and wet heat treatment. The drug underwent degradation under acidic, basic and photolytic conditions. The degraded products were well separated from the pure drug. Statistical analysis proved that the developed method, used for quantification of TAM as a bulk drug and present in pharmaceutical tablets, was reproducible and selective.

     

HPTLC Estimation of Oroxylin A in Oroxylum indicum Herbal Formulations

JPC – Journal of Planar Chromatography – Modern TLC - Oroxylum indicum (L.) Kurz is an important medicinal plant with a wide spectrum of medicinal properties. It is frequently used in a...     

旋转微扰法用于确定化学体系的组分数

本文提出了一个新的用于估计化学体系组分的化学计量学方法,方法的基础在于具有化学意义的特征子空间对微扰和数据的旋转变换具有较大的稳定性,通过观察多次实验中投影残差的标准方差来确定化学秩。对实际化学体系的分析结果表明,该法为组分数的估计提供了一个有价值的工具。     

Stability-Indicating HPTLC Method for the Determination of Tamsulosin in Pharmaceutical Dosage Forms

A simple, sensitive, selective, precise and stability indicating high-performance thin-layer chromatographic method was developed for the determination of tamsulosin (TAM) in bulk and tablet formulation. Validation was carried out in compliance with International Conference on Harmonization guidelines. The method employed thin-layer chromatography aluminium plates pre-coated with silica gel 60F₂₅₄ as the stationary phase and the mobile phase consisted of acetonitrile/methanol/dichloromethane (2.0: 1.0: 2.0, v/v/v). This solvent system was found to give compact spots for tamsulosin (R _f = 0.27 ± 0.02). Densitometric analysis of TAM was carried out in the absorbance mode at 286 nm. Linear regression analysis showed good linearity (r ² = 0.9993) with respect to peak area in the concentration range of 300–800 ng per band. The method was validated for precision, accuracy, ruggedness and recovery. Limits of detection and quantitation were 8.49 and 25.72 ng per band, respectively. TAM was subjected to acid and alkali hydrolysis, oxidation, photo degradation, dry heat and wet heat treatment. The drug underwent degradation under acidic, basic and photolytic conditions. The degraded products were well separated from the pure drug. Statistical analysis proved that the developed method, used for quantification of TAM as a bulk drug and present in pharmaceutical tablets, was reproducible and selective.     

Rapid and Sensitive HPTLC Method for Determination of Epalrestat in Human Plasma

JPC – Journal of Planar Chromatography – Modern TLC - Epalrestat is a new drug for diabetic neuropathy. A new, simple, rapid very sensitive, and accurate high performance thin-layer...