Abstract
Purpose::
The purpose of this research is to study the uptake of Bevacizumab (Avastin®) loaded Poly lactide- co-glycolide (PLGA) nanoparticles by ARPE-19 cells.
Methods::
PLGA 5050 [D, L- lactide: glycolide = 50: 50, Mw 45,000 - 75,000 da] was employed to prepare fluorescein isothiocyanate labeled Ig-G (FITC IgG), FITC labeled bovine serum albumin (BSA) and Bevacizumab loaded nanoparticles. PLGA nanoparticles encapsulating model compound FITC IgG and Bevacizumab were prepared by the water- in oil- in water (w/o/w) type of emulsion and were characterized in vitro, by evaluating their entrapment efficiency and particle size. Retinal pigmented epithelial cell line (ARPE-19) was used to perform the basolateral uptake studies of nanoparticles. Samples containing FITC labeled IgG were analyzed using fluorescence spectrophotometer and that of bevacizumab will be analyzed using specific ELISA method.
Results::
Entrapment efficiencies were about 85%, 65% and 80% for the FITC-IgG, FITC-BSA and Bevacizumab respectively. Mean particle sizes for all nanoparticles were approximately about ~ 210nm. Basolateral uptake studies shows that model compound FITC-IgG loaded nanoparticles have a greater uptake into the ARPE-19 cells compared to the control solution. Uptake of nanoparticles was about 1.23 folds higher than the control. Similar results were obtained with FITC-BSA where the increase was about 1.19 folds than the control. The possible reason for increased uptake of compounds by the retinal cells using nanoparticles over the control could be attributed to endocytosis.
Conclusions::
Preliminary results show that large macromolecules when encapsulated in nanoparticles have higher uptake into the retinal cells. This strategy can be employed for the trans-scleral delivery of bevacizumab nanoparticles upon subconjunctival administration for the treatment of age related macular degeneration.
Keywords: age-related macular degeneration • retinal pigment epithelium • sclera