Der Pharmacia Lettre
Abstract
Author(s): Krishnan P.N, Saraswathi R, Dilip C, Rama Rao N, Sambasiva Rao K.R.S, Raghvendra
To formulate and evaluate Acyclovir microcapsules using biodegradable and non-biodegradable
polymers namely egg albumin, guar gum and ethyl cellulose and its invitro evaluation. The
Acyclovir microcapsules were prepared using different concentrations of egg albumin, guar gum
and ethyl cellulose. The microcapsules were prepared using solvent diffusion method and heat
coagulation method. The microcapsules were then studied for entrapment efficiency at two
different stirring speeds, drug polymer compatibility and surface morphology. The invitro
release study was also done. Further kinetic modeling was employed to find out the release
mechanisms. Acyclovir loaded microcapsules formulated with guar gum showed an entrapment
efficiency of 92.97%, with ethyl cellulose 91.96% and the entrapment efficiency with egg
albumin was 90.61%. The SEM showed that the microcapsules were free flowing, non
aggregated and spherical between 700-1000 �Ž�¼m in diameter. The surface was wavy in
microcapsule formulated with guar gum, porous in microcapsules using ethyl cellulose and
smooth in the case of microcapsules formulated with egg albumin. The FTIR spectrum showed
that there is no interaction between the polymer and the drug. The invitro release study was
found to be the best in the case of acyclovir microcapsules formulated with guar gum. The rate of
drug release follows a time dependent process based on fickian diffusion and korsemeyerpeppas
model that the drug release is by diffusion and by erosion. The acyclovir microcapsules
using various polymers can be used as oral controlled delivery of the antiviral drug acyclovir.
