Quantitative [1]H NMR spectroscopy for analysis of topiramate in presence of its degradation products

ABSTRACT

High-resolution NMR Spectroscopy is a powerful tool in the elucidation of a structure with respect to constitution, configuration and conformation. In recent years, NMR has increasingly used in quantitative analysis. In the present study, we describe the degradation of topiramate under different ICH stress conditions [acid, base, oxidation, neutral], and show the ability of [1]H NMR for selective determination of drug substance and drug product. The NMR method described here is able to determine the content of topiramate in presence of less than 1.0% of its degradation products. The limit of detection and quantification were found to be 0.04 mM/0.5 ml and 0.13 mM/0.5 ml DMSO-d[6] respectively. The described method has advantages over the reported methods as the assay was completed in less than 3 min with high accuracy and selectivity. It is concluded that [1]H NMR is a versatile concept for routine analysis with respect to time and cost. The method was validated according to ICH guidelines with satisfied results and can be successfully applied for quality evaluation and stability testing