OBJECTIVE:To prepare aciclovir (Acv) carbomer(Cb) ethylcellulose(
EC)
microspheres with good
bioadhesion and
sustained drug release.METHODS:The microspheres were prepared using a w/o emulsion solvent evaporation technique.The bioadhesion was evaluated via counting the microspheres retaining at the surface of gastric mucin. In vitro drug release was also studied.The factors influencing the bioadhesion and drug release,such as Cb/Ec ratios,Acv
content,
particle size as well as the pH of media were studied,respeitively.RESULTS:While Cb/Ec ratio being increased,the bioadhesion of Acv Cb Ec microspheres increased,but teh drug
Release rate slowed down,which showed a negative correlation.The more the Acv content was,the worse the bioadhesion was and the faster Acv released.When the Acv content was ≤20%,the drug release rate slightly changed.The bioadhesion of the microspheres was also reduced when the particle size was increased.However when the particle sizes were between 500～1200 μm,the drug release rate was significantly retarded (12 h).In acedic media,the drug release rate was faster than that in neutral media.CONCLUSION:The Acv Cb Ec microspheres had a good bioadhesion and sustained drug release when Acv content was ≤20%,the particle size was between 500～1200 μm and the Cb/Ec ratio was 1∶9.The drug released even slower in neutral media.
More abstracts about the The bioadhesive property of aciclovir microspheres on animals gastric mucin and its in vitro ef