PREPARATION AND SOLUBILITY ENHANCEMENT OF SOLID DISPERSION OF POORLY SOLUBLE LISINOPRIL DRUG
*Sadiya Karim, Md. Abdul Aali Khan and Rajesh Singh Pawar
ABSTRACT
The poor solubility of drug substances in water and their low dissolution rate in aqueous G.I.T fluid often leads to insufficient bioavailability. Lisinopril is an angiotensin converting enzyme inhibitor (ACEI) used to treat hypertension, heart failure and myocardial infarction. It functions by inhibition of angiotensin converting enzyme as well as the renin angiotensin aldosterone system. It is characterized with poor solubility which limits its absorption and dissolution rate which delays onset of action. The objective of the present study was to enhance the dissolution characteristics of the model drug by increasing the solubility and release rate of Lisinopril through solid dispersions using polyethylene glycol and polyvinylpyrrolidone polymers by the solvent evaporation method. The compatibility analysis was carried out through Fourier Transform-Infrared Spectroscopy (FT-IR). The kinetic studies for drug release mechanisms were characterized through zero-order, first-order, Higuchi, Korsmeyer-Peppas, and Hixson-Crowell models. The dissolution analysis of solid dispersions showed exhibited more than 92.45% drug released. The optimized formulation was found to follow the Higuchi model of drug release kinetics with an R2 value of 0.993. Solid dispersions containing PEG and PVP polymers prepared through the solvent evaporation method exhibited significant enhancement in the release profile compared to a pure drug, lisinopril.
Keywords: Lisinopril, Bioavailability, Solvent evaporation method, Kinetic studies, Higuchi model.
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