Swellable drug-polyelectrolyte matrices of drug-carboxymethylcelluylose complexes. Characterization and delivery properties

MARÍA V. RAMÍREZ RIGO; DANIEL ALBERTO ALLEMANDI; RUBEN MANZO,

TAYLOR & FRANCIS INC

Año: 2009 vol. 16 p. 108 - 108

his article reports the development and delivery properties of swellable drug-polyelectrolyte matrices prepared with complexes of the acid form of carboxymethylcellulose (HCMC). Drug-polyelelectrolyte complexes (HCMC-D) were obtained by neutralization of HCMC with two model basic drugs (atenolol and metoclopramide). Characterization through FT-infrared spectroscopy, power X-ray diffraction, and DSC indicates the ionic nature of the interaction between the carboxylic groups of HCMC and the basic group of D. Matrices prepared by compacting (HCMC-D) alone or in a mixture with sodium carboxymethylcellulose were subjected to measurements of solvent up-take, dynamics of swelling, and release kinetics. Delivery rate of mixed matrices is a function of its composition and may be widely modulated. They exhibited anomalous delivery kinetics with Korsmeyer exponent n in the range 0.67?0.87. Experimental results indicate that the erosion of the hydrogel layer is the main delivery process.