In vitro characterization of new stabilizing albumin nanoparticles as a potential topical drug delivery system in the treatment of corneal neovascularization (CNV)
The aim of this work was to study the preparation process and the in vitro release of human serum albumin nanoparticles stabilized by Gantrez (R) ES-425, which was loaded with antiangiogenic drugs (suramin and bevacizumab). Nanoparticles were prepared by coacervation and stabilized with Gantrez (R) ES-425(Nps-Ga). As control, albumin nanoparticles cross-linked with glutaraldehyde (Nps-Glu) were prepared. Nps-Ga displayed a mean size of about 210 nm whereas Nps-Glu showed a mean size of 158 nm. For suramin-loaded nanoparticles, the stabilization process did not show any significant effect on the drug with neither glutaraldehyde nor Gantrez (R). On the contrary, for bevacizumab, only nanoparticles stabilized with Gantrez (R) displayed important payloads (97 mu g/mg nanoparticle) of the active form of the antibody. For nanoparticles with glutaraldehyde, only a very low amount of the loaded bevacizumab remained active. Regarding the in vitro release studies, suramin showed a release mechanism influenced by the type of stabilizing agent. Finally, bevacizumab released from Nps-Ga was characterized by a small burst effect followed by a sustained release rate. In summary, albumin nanoparticles stabilized by polymer coating were successfully obtained and are a promising delivery system for the topical treatment of CNV.