Assays of active ingredient content and dissolution of oral dosage forms containing amoxicillin trihydrate and sulbactam pivoxil by HPLC

M. F. RAZUC; F. CABRERA; GARRIDO, M.; M. V. RAMIREZ RIGO

Congreso; 6ta Reunión Internacional de Ciencias Farmacéuticas; 2021

Amoxicillin trihydrate (AMO)/sulbactam pivoxil (SP) are commercialized in solid oral forms. This combination has not been reported in any pharmacopoeia. Moreover, there are no dissolution studies of AMO/SP formulations in the literature and only one study devoted to their determination in tablets, where AMO/SP ratio of 1:1 is analyzed. The purpose of the present work is the application a new HPLC/UV method to perform the analytical determination of AMO and SP in oral formulations, both in assay and dissolution studies, even at the more challenging AMO/SP ratio of 7:1. The HPLC method used a reverse phase C18 column with a mobile phase consisting of acetonitrile and water (80:20 v/v) in isocratic mode. The samples analyzed were oral tablets and suspensions (AMO/SP ratio from 1:1 to 7:1). The dissolution study was carried out testing several media of sodium lauryl sulfate, polysorbate 20 and polysorbate 80. The conditions used were: apparatus II at 75rpm, 900mL of medium and a temperature of 37±0.5°C. The maximum dissolved percentages achieved (99% for AMO and 91% for SP) were obtained when polysorbate 20 (0.10% w/v) was used as medium. The HPLC method was suitable for the determiation of AMO and SP (recovery 91.2-100%) in tablets and oral suspensions, even in formulations where the AMO/SP ratio was as high as 7:1.