TY - JOUR AU - Anelchyk, G.V. AU - Alexandrova, D.I. AU - Maltsev, G.V. AU - Yegorova, A.V. AU - Antonovich, V.P. AU - Giher, ZA. PY - 2009/08/25 Y2 - 2024/03/28 TI - Validation of the spectrophotometric method of the determination of sildenafil citrate in tablet form JF - Farmatsevtychnyi zhurnal JA - Farm Zh VL - 0 IS - 4 SE - Original Articles DO - UR - https://pharmj.org.ua/index.php/journal/article/view/965 SP - 94-101 AB - The express spectrophotometric method of quantitative determination of sildenafil citrate in ta­blets «Intagra» (JV «InterChem») has been developed and validated. Values of constants of ionisation sildenafil (pK1 = 3,66, pK2 = 5,17 and pK3 = 10,03) have been calculated. To confirm the bioequivalence by comparative researches in vitro the determination of dissolution profiles of the drug-generic «Intagra» (JV «InterChem) and a referent drug «Viagra» («Pfizer») in three media with values of pH 1,2; pH 4,5 and pH 6,8 has been spent. Values of factors of similarity f2 which values testify to equivalence of drugs have been calculated. ER -