Biopharmaceutical properties of a polyelectrolyte- enalapril complex.

RAMÍREZ RIGO, M.V.; QUINTEROS, D.A.; ARDUSSO, M.S; OLIVERA, M.E.; ALLEMANDI, D.A.; MANZO, R.H.

Tandil

Congreso; Congreso SAFE; 2008

Sociedad Argentina de Farmacología Experimental

In a R+D project on drug delivery systems, enalapril (Ena) was selected as a  model of peptide-mimetic drug to be associated to a polyelectrolyte carrier (PE). This drug is absorbed by PEPT1 and 2 transporters and has low oral bioavailability (36- 44%). It has basic and acid groups able to interact with PE. The aim of this work is to study the biopharmaceutical properties of an aqueous dispersion of (PE-Ena) complex. Drug release evaluation was performed using different receptor media. The complex solution of pH~5,7 released Ena slowly when the medium is water. Release rate is increased as water is replaced by physiological solutions. In both cases the data fits the linear kinetic model. The ionic interaction modulates the release rate. Evaluation of intestinal permeability was performed in everted rat intestine. It was observed an enhancer effect of the PE because it increase 1.7 times the speed of Ena permeation. The mechanism is not clear and it is necessary complementary experiments to determine it. The complex solutions can be consider like a drug carrier system of Ena that increases the drug permeation and could improve the bioavailability of the drug.