ACYCLOVIR-SILICA COMPOSITE AS PLATFORM FOR DEVELOPMENT OF NOVEL ORAL DOSAGE FORM OF DRUG WITH PROLONGED RELEASE

Abstract

In this work the possibility of creation of novel dosage form of acyclovir based on colloid silica for oral administration, which is capable of long sustained release of the drug is estimated. Clinical practice has shown that the traditional oral dosage form of acyclovir has serious drawbacks, one of which is the rapid elimination of the drug from the body. Colloid silica is recognized as a safe food additive in Russia and around the world. This is of particular importance for the development of drug oral dosage forms. The composite was synthesized by acid-catalyzed sol-gel reactions (hydrolysis and polycondensation) of tetraethoxysilane. The acyclovir solution was introduced into the prehydrolyzed silica sol. In experiments in vitro, a kinetic release profile of acyclovir encapsulated in the silica matrix was obtained. The amount of the released drug was determined spectrophotometrically using a spectrometer Carry 100, Varian, Australia. An experimental simulation of kinetics of the release of acyclovir from the synthesized composite in various sections of the gastrointestinal tract was carried out taking into account the literature data on drug transit time through the sections and medium pH in them. The results obtained in this work showed that the sol-gel encapsulation of acyclovir in silica matrix led to the formation of the acyclovir-silica composite, which is able to maintain the concentration of the drug in various sections of the gastrointestinal tract for 26 h regardless of the medium acidity and transit time of the drug through the sections. Thus, the synthesized composite of acyclovir with silica can serve as a platform for further development of a new oral dosage form of prolonged action.