Theophylline extended-release monolithic matrix comprising natural rubber latex as binder

Abstract

Abstract A major component of polymer in natural rubber latex (NRL) obtained from Hevea brasiliensis consists of poly-cis-1,4-isoprene. Poly-cis-1,4-isoprene exhibited interesting physical properties suitable for possible use as a binder in pharmaceutical solid dosage forms such as monolithic matrix tablet. The aim of this study was to study the feasibility of using NRL as the binder in theophylline anhydrous (THE)-incorporated monolithic matrix tablet in comparison with polyvinyl pyrrolidone K-30 (PVP-30). Physical properties of granules and tablets fabricated with wet granulation and tableting process, in vitro drug release test and release kinetic model were investigated and compared with those prepared using PVP-K30 as a binder. THE-incorporated monolithic matrix tablet was successfully fabricated with wet granulation and tableting process using NRL or PVP-K30 as binder. Granules and tablets of monolithic matrix tablet using NRL as a binder exhibited similar physical properties to those of tablet prepared using PVP-K30 as a binder. In addition, the controlled THE release with diffusion mechanism were presented in both formulations. Surprisingly, the addition of sodium bicarbonate in THE monolithic matrix tablets employing NRL as a binder could also prolong the drug release.</jats:p