Influence of Natural Stabilizers on Esomeprazole Nanocrystals Prepared by Antisolvent Precipitation Method for Enhanced Oral Bioavailability

Abstract

Esomeprazole is a low-aqueous solubility proton pump inhibitor that also leads to a low oral bioavailability, solubility and dissolution rate to maximize therapeutic efficacy. The antisolvent precipitation method was used to prepare nanocrystals of esomeprazole using several stabilizers such as guar gum, karaya gum, and polyethylene glycol 400 (PEG 400). Eight formulations (F1–F8) had been formulated. The formulations were compared on the basis of size of particle, content uniformity and in vitro drug release. The optimized formulation along with drug and polymers were subjected to characterization studies.

Results: This optimized formulation (F8) showed a 99 percent drug release in 5 minutes, much higher compared to pure drug. The FTIR test was done to prove the lack of drug stabilizer interactions and the excipient compatibility. The DSC results showed a decrease in crystallinity indicating the formation of nanocrystals. Improved dissolution was credited to smaller particle size, greater surface area and good stabilization.

Conclusion: Antisolvent precipitation is an efficient and easy process to synthesize stable esomeprazole nanocrystals with increased dissolution rates, which may lead to an improved oral bioavailability.