ABSTRACT
Objective: The aim of this study is to prepare floating hollow microspheres encapsulating Sorafenib (SFN) to enhance its oral bioavailability. Methods: Gastro-floating hollow adhesive microspheres containing SFN were produced by using an emulsion solvent evaporation technique with ether and ethanol as solvents. Ethyl cellulose and carbopol 934P were used as the encapsulating carriers. The effects of formulation parameters like, solvent volume ratio, and drug to polymer ratio (D: P ratio), encapsulation efficiency percentage EE%, floating percentage, and release of SFN after 12 h (Rel12) were investigated and analyzed using a (32) full factorial design. Results: The floating percentage of the microspheres was found to be 76.5%. The in vitro drug release from these hollow microspheres followed the Higuchi model equation. The in vivo results showed that approximately 1.96-fold improvement in the relative bioavailability of the microspheres compared with that of the commercial tablet. Conclusion: The results demonstrate that the hollow microspheres with good gastro-floating ability are a promising delivery system to enhance SFN bioavailability.
ABSTRACT
Dipyridamole,a widely used drug in clinics that inhibits platelet agregation,also shows great potential for anti-vi- ral and anti-tumor effect in recent years. However,with its poor and pH-dependent solubility as well as the narrow absorption window in the gastrointestinal tract,the conventional oral dosage forms have problems of low bioavailability,high inter-subject variability and insufficient drug efficacy. The novel drug delivery systems based on solid dispersion,gastro-floating,microenvironmental pH-modifica- tion,drug-protein complex and nanoparticle technologies are the effective methods to enhance oral drug absorption. In this paper we re- view the recent advances in novel dosage form and preparation technology of dipyridamole,to provide references for development of novel preparation with good safety,therapeutic efficacy and patient compliance.