Evaluation of parameters involved in preparation and release of drug loaded in crosslinked matrices of alginate

Parameters affecting the characteristics of the drug loaded crosslinked sod ium alginate matrix films and the release of metoclopramide hydrochloride a nd cisapride from these matrices were studied. It was shown that the releas e rate is influenced by the crosslinking technique of the matrix film, cros slinker type and concentration, drug physico-chemical properties especially solubility and the molecular weight, acidity of the release medium, concen tration and the loaded quantity of the drug in the matrix. The crosslinking process of the matrix film was shown to be an interfacial phenomenon and t he nature of crosslinking depends on the crosslinker type and concentration . This work also showed that crosslinked alginate in a matrix form has limi tation in practical use due to the effect of acidic medium on the crosslink ing of the matrix film and hence, the rate of drug release. (C) 1999 Elsevi er Science BN. All rights reserved.