Quasi emulsion spherical crystallization technique based environmentally responsive Tulsion® (pH dependent) microspheres for colon specific delivery
pH-dependent sustained-release Tulsion® microspheres bearing clarithromycin were prepared using quasi-emulsion solvent diffusion method with thermocoat L 30 D 55 as a release retardant. Both, clarithromycin and thermocoat L 30 D 55, were found to be non-hemolytic during in vitro toxicity assay against human red blood cells.