Isolation and characterization of process related impurities and degradation products of bicalutamide and development of RP-HPLC method for impurity profile study.

A reversed-phase high-performance liquid chromatographic method was developed for determination of process impurities and degradation products of bicalutamide in bulk drug and pharmaceutical formulations. The separation was accomplished on a Symmetry C(18) (4.6 mm x 250 mm; particle size 5 microm) column under isocratic mode. The mobile phase was 0.01 M KH(2)PO(4) (pH 3.0):acetonitrile (50:50 v/v) and a PDA detector set at 215 nm was used for detection. Forced degradation of bicalutamide was carried out under thermal, photo, acidic, alkaline and peroxide conditions. The unknown process impurities and alkaline degradation products were isolated and characterized by ESI-MS/MS, (1)H NMR and FT-IR spectral data. Under alkaline conditions bicalutamide was degraded in to an acid and an amine. The kinetics of degradation was studied. The proposed method was validated and successfully applied to the analysis of commercial formulations. Thus, the developed method can be used for process development as well as quality assurance of bicalutamide in bulk drug and pharmaceutical formulations.