كليدواژه :
Microencapsulation , Release rate , ميكروانكپسولاسيون , Kinetic of release , اتيل سلولز , Non-solvent , ميكروكپسول هاي پرس شده , Non-solvent addition technique , پزشكي , cellulose acetate phthalate , روش افزودن ناحلال , كينتيك آزادسازي , Ethylcellulose , سرعت آزادسازي , علوم دارويي , سلولز استات فتالات , Tableted microcapsules
چكيده لاتين :
Acetyl salicylic acid (ASA) was encapsulated with cellulose acetate phthalate (CAP), ethylcellulose (EC) or their mixtures by an emulsion non-solvent addition method. The release profiles of prepared microcapsules with different ratios of drug to polymer (10:1 and 4:1) and tableted microcapsules were evaluated at pH 1.2 or 6. The results showed that a reduction in the ratio of drug to polymer resulted in a reduction in release rate. The microcapsules prepared with EC showed the lowest release rate. The in vitro release studies showed that the drug release rate decreased after tableting, because of the formation of a non-disintegrating matrix. Release of ASA at pH 6 is significantly higher in all microcapsules, even when using EC which is not water soluble. This is probably due to better solubility of ASA at pH 6 indicating incomplete film formation around the ASA particles.Release data were examined kinetically and the ideal kinetic models were estimated for drug release. The results showed that for tableted microcapsules the highest correlation coefficient was achieved with the zero-order release. For tableted microcapsules containing CAP or the mixture of CAP and EC contribution oferosion was higher than that of untableted microcapsules.
