Enteric coated micro-particles for targeted and controlled release

摘要

This work is focused on production of enteric coated microparticles for oral administration, using a water-in oil-in water (W1/O/W2) solvent evaporation technique. The active agent theophylline (TP) is encapsulated in cellulose acetate phthalate (CAP), a pH-sensitive polymer available on the market, which is insoluble in acidic media, but dissolves at neutral pH (above pH 6). Some preliminary tests are carried out using a novel synthesized pH-sensitive poly(methyl methacrylate-acrylic acid) copolymer, P(MMA-AA), which is checked to replace CAP in theophylline enteric coated microparticles.