Chitosan Nanoparticles Modified by Anredera cordifolia (Ten.) Steenis Leaf Extract for Enhancement of Azithromycin Encapsulation Efficiency and Loading Capacity: In vitro Drug Release Study

The encapsulation efficiency and the loading capacity of azithromycin (AZI) were succesfully enhanced by modifying chitosan nanoparticle (NCh) with Anredera cordifolia leaf extract (ACLE), as demonstrated in this study. The prominent secondary metabolites in ACLE could establish a new chemical bonds with NCh's amino groups and partly improved the hydrophobicity of NCh, which leads to excellent AZI encapsulation efficiency and loading capacity of 95.24 ± 1.30% and 55.74 ± 1.03%, respectively. TEM characterization demonstrated that the AZI-loaded ACLE-NCh nanoparticles were uniformly distributed with a particle size of 24.6 ± 2.9 nm. According to the result of in vitro drug release studies, AZI-loaded ACLE-NCh releases 1.12 ± 0.33% at a pH of 1.6 for 2 h, 82.05 ± 2.26% at a pH of 6.8 for 6 h, and 93.44 ± 1.94% at a pH of 7.4 for 24 h. It is remarkable that the encapsulation activityu of AZI-loaded ACLE-NCh is more effective due to the better interaction between NCh and AZI resulting from the increased hydrophobicity of modified NCh. Moreover, this work provides novel findings on the significant contribution of NCh modified by plant extracts, which has the potential as a carrier for azithromycin.