A simple, economical, and accurate absorption ratio method in UV Spectroscopy and HPTLC method were developed for the simultaneous estimation of Amlodipine besylate (AML) and Nevirapine (NEV) in bulk and tablet dosage form. In Spectroscopy, 0.1M HCl was used as a diluent to dissolve AML and NEV. The absorptions were observed at 252 nm (isobestic point) and 295 nm (?max of NEV), which were selected based on overlapping spectra of AML and NEV. The linearity range of the UV method was found to be 3-7 µg/ml at 252 nm for AML (r2=0.9995±0.0005) and 295 nm for NEV (r2=0.9985±0.0012). HPTLC method was developed with silica gel GF TLC Plate. Chloroform-Methanol-Glacial acetic acid (75.8:21.6:2.6) was used as a diluent. The spot after the chromatogram was identified in UV and Iodine chamber. The linearity range of HPTLC method was found to be 5-25 µg/ml for AML (r2=0.9994) and 295 nm for NEV (r2=0.999). Recovery study of UV and HPTLC methods were performed to confirm the accuracy of the... Это и многое другое вы найдете в книге Method development of Amlodipine and Nevirapine by UVS and HPTLC (Sathis Kumar Dinakaran and Narayudu Yandamuri)