The effect of different desolvating agents on BSA nanoparticle properties and encapsulation of curcumin

The desolvation method was successfully used to prepare nanoparticles from bovine serum albumin (BSA) using ethanol, acetone, and their mixtures (70:30 and 50:50, respectively). Ethanol and mixtures of ethanol and acetone led to the most spherical nanoparticles, while using pure acetone resulted in a mixture of spherical and rod shape nanoparticle. Acetone was the solvent with higher encapsulation efficiency equal to 99.2 +/- 0.36 %. The polydispersity values of BSA NPs in this study were 0.045 +/- 0.007, 0.065 +/- 0.013, 0.091 +/- 0.012, and 0.120 +/- 0.016 for ethanol (100) 4x, Et:Ac (70:30) 4x, Et:Ac (50:50) 4x, and acetone (100) 3x, respectively. Encapsulation efficiencies of curcumin inside BSA NPs were 19.4 +/- 2.2 and 19.8 +/- 1.6 % for 1.0 and 1.5 molar ratios of curcumin to BSA, respectively. Crosslinking using glutaraldehyde improved the stability of BSA NPs and curcumin-loaded BSA NPs and both groups of nanoparticles were stable for 1 month; the lyophilized curcumin-loaded BSA NPs were able to redisperse in water. The particle size and polydispersity index of redispersed NPs were higher than the original NPs before lyophilization. The size distribution study shows that after 10 s of sonication most nanoparticles were well dispersed; however, a small but significant fraction formed aggregates. Sonication for 10 s decreased the effective diameter and polydispersity of the redispersed nanoparticles, while increasing the sonication time to 20 s did not show significant changes. In vitro release study of curcumin from BSA NPs showed that these biocompatible nanoparticles have the ability to be used as a carrier to improve controlled release of curcumin.