Spectrophotometric determination of terbinafine in presence of its photodegradation products.

Spectrophotometric methods have been developed for the quantitative determination of terbinafine hydrochloride in presence of its photodegradation products. The methods make use of the first spectral derivation (1D) and the first derivative of the ratio spectra (1DD) of the named drug and its photodegradates at different justified wavelengths. Good linearity was observed in the range of 10-100 mg.ml-1 with low LOD (> or = 1.11 mg.ml-1) and LOQ (> or = 3.36 mg.ml-1). The proposed methods showed good linearity, precision and reproducibility.