Formulation and Characterization of Isradipine Nanoparticle for Dissolution Enhancement


Isradipine belong to dihydropyridine (DHP) class of calcium channel blockers (CCBs). It is used in the treatment of hypertension, angina pectoris, in addition to Parkinson disease. It belongs to the BCS class II drug (low solubility-high permeability). The drug also suffers from extensive first pass metabolism, therefore it had low bioavailaility of approximately 15-24%.The aim of this study was to formulate and optimize a stable nanoparticles of this highly hydrophobic drug by solvent- antisolvent precipitation method to enhance in vitro dissolution rate and improve drug bioavailabilityTen formulas of isradipine nanoparticles were prepared by antisolvent precipitation method utilizing one of these polymers Poloxamer 188, PVA, and Soluplus at different drugs: polymer ratios. The particle size, and polydispersity index (PDI) were investigated.Among all the prepared nanoparticles formulas, formula (F9) which contain Soluplus as a stabilizer at polymer: drug ratio of (1:0.75) and solvent: antisolvent ratio of (1:9) was considered as the optimum formula which showed increment in the solubility to about 10 times than that of the pure drug. The investigations of the drug–excipients compatibility studies by FTIR and crystalline state by DSC, were done. Moreover, the analysis by DSC of the nanoparticles of the selected formula (F9) indicated a reduction in the crystallinity and amorphization of the drug. In addition, FTIR result indicates that hydrogen bond may be formed between soluplus and the drug, which it may have a contribution to increase affinity between them and resulted in enhanced solubility . The results of dissolution study showed a significant increase in dissolution rate through particle size reduction . So, it can be concluded that solvent- antisolvent precipitation method was an efficient method for preparation of isradipine nanoparticles for dissolution enhancement