RELEASE OF ACYCLOVIR FROM SEMISOLID DOSAGE FORMS - A SEMIAUTOMATED PROCEDURE USING A SIMPLE PLEXIGLASS FLOW-THROUGH CELL

A simple plexiglass flow-through cell (PFTC) was designed and utilized to monitor the release of acyclovir from two different semi-solid preparations. The influence of membrane type, flow rate and temperature was investigated. A small difference in temperature (32-37 degrees C) had a significant effect on the release rate as did increasing flow rates from 2.9 to 10.0 ml/min. Cellulose acetate membranes showed a greater degree of release when compared with polytetrafluoroethylene and polyvinylidine difluoride membranes. The rank order of release of acyclovir between the two different semi-solid preparations remained the same irrespective of the membrane type, flow rate or temperature used during these studies. Data obtained from these experiments indicate that the plexiglass flow-through cell is a simple, reproducible and reliable tool which can be readily applied to assess the pharmaceutical availability of drugs from semi-solid dosage forms.