Development and validation of the stability indicating RP-UHPLC method for the determination of the chemical purity and assay of bimatoprost.

A simple, rapid and accurate ultra-high performance liquid chromatographic (UHPLC) method with a UV detection for the determination of the chemical purity and assay of bimatoprost (BT-1) was developed. The chromatographic separation was achieved with the use of an Acquity BEH C8, 150 × 2.1 mm, 1.

Use of the hyphenated LC-MS/MS technique and NMR/IR spectroscopy for the identification of exemestane stress degradation products during the drug development.

Exemestane (6-Methyleneandrosta-1,4-diene-3,17-dione) active pharmaceutical ingredient (EE-3) was subjected to thermal, photolytic, oxidative, acidic and base stress conditions prescribed by the ICH (International Conference on Harmonization) guideline Q1A(R2). EE-3 was found to degrade in base, acidic and oxidative conditions. Eleven new degradation products of EE-3 were characterized by the LC-MS/MS technique.

A novel method for the determination of chemical purity and assay of menaquinone-7. Comparison with the methods from the official USP monograph.

An HPLC method with UV detection and separation with the use of a C30 reversed phase analytical column for the determination of chemical purity and assay of menaquinone-7 (MK7) in one chromatographic run was developed. The method is superior to the methods published in the USP Monograph in terms of selectivity, sensitivity and accuracy, as well as time, solvent and sample consumption. The developed methodology was applied to MK7 samples of active pharmaceutical ingredient (API) purity, MK7 samples of lower quality and crude MK7 samples before purification.

Development and Validation of a UHPLC UV Method for the In-Process Control of Bosentan Monohydrate Synthesis.

Bosentan monohydrate (4--butyl--[6-(2-hydroxyethoxy)-5-(2-methoxyphenoxy)-2-(pyrimidin-2-yl) pyrimidin-4-yl]benzene-1-sulfonamide monohydrate) is a dual endothelin receptor antagonist (ERA) applied in the treatment of pulmonary arterial hypertension. To achieve effective process control of the bosentan monohydrate synthesis, it was necessary to develop a selective and not highly time-consuming method for ultra-high performance liquid chromatography (UHPLC). The method is characterized by adequate sensitivity, reproducibility and selectivity for the determination of bosentan monohydrate and related compounds from all synthetic stages.

A Validated TLC-Densitometric Method for the Determination of Mesterolone in Bulk Material and in Tablets.

Mesterolone is a synthetic androgenic steroid indicating a weak anabolic activity. A new, simple in use, and economical TLC-densitometric method in normal phase system (NP-TLC) has been developed and validated for the identification and quantitative determination of mesterolone in bulk drug and in tablet formulation. NP-TLC analysis was performed on aluminium plates precoated with silica gel 60F254 as the stationary phase using chloroform-acetone (40 : 10, v/v) as mobile phase.