The Preparation Of Atenolol Sustained Release Matrix Tablets

Atenolol (ATN) belongs to the β-receptor blocker, which has the main effect onhypertension, angina, arrhythmia and glaucoma and so on. However, the common dosageform of the drug has a low bioavailability and the individual difference is severe, which iseasy to cause the blood concentration peak valley phenomenon. It cannot obtain a stable effecton the anti-hypertension. In order to deal with the problems mentioned above, EC andhexadecanol were taken as basic materials to prepare the ATN sustained release matrix tabletsin this paper.In this study, a UV method was used for the determination of the equilibriumsolubility of atenolol in oil and aqueous phase. According to the literature, UV spectrophoto-metry was adopted for the determination of ATN during the study of drug release rate.These methods were accurate and quick which could meet the requirement of the analysisperfectly.Basing on the studies of the influencing factors in formulation and manufacture on therelease profile, optimal formulation modified to release drug over12h was obtained bycentral composition design–response surface optimization method and the optimal formula-tion of the ATN sustained release tablet was screened. The best formulation includes EC asthe retard and hexadecanol as an assistant adjuvant which has sustained release effect togetherwith the magnesium stearate. ATN sustained release matrix tablets were prepared by directcompression method and the cumulated release rate achieved was over80%.The release mechanism of ATN was studied by comparing zero-order model,first-order model, Higuchi model and Ritger-Peppas model et al. Release data were in goodlinearization with the Higuchi equation with correlation coefficient r value of0.991. Therelease data were also in accordance with Ritger-Peppas equation with correlation coefficientr value of0.976, indicating that drug diffusion was the prevailing release mechanism witherosion as a supplementary release mechanism.