Method Development and Validation of Natamycin Using UV-Visible Spectroscopy and Forced Degradation Studies Using HPLC

Abstract

A simple, sensitive, rapid, precise, accurate UV Visible Spectrophotometric method and Stability indicating assay HPTLC Method has been developed for Natamycin in their dosage form and in marketed formulation. The method was developed using methanol in UV and Dimethyl Sulphoxide as solvent. The mobile phase of Chloroform: Methanol: Glacial acetic acid: Water (10: 3: 3:1, v/v/v/v) was used for optimized separation of degradation products. The drug shows different absorption maximas due to presence of strong chromophores in the compound. Natamycin contains chromophores and shows four maxima in its UV absorption spectrum (220, 280, 303 and 318 nm) respectively. The absorption maxima for natamycin was taken at 303 nm as it shows maximum absorbance at this particular wavelength. The Beer-Lambert law was obeyed from the range of 2-10 μg/mL for UV and 1000-3000ng/spot for HPTLC concentration range. The method was able to separate all the degradation peaks formed in ICH prescribed stress conditions with sufficient difference in Rf values. The developed method was validated in terms of linearity, accuracy, precision, repeatability, limit of quantification, limit of detection, robustness, and assay as per International Conference on Harmonization (ICH) Q2 (R1). The utility of this developed method was demonstrated by the assay of commercially available Natamet (natamycin ophthalmic eye suspension) formulation.