Surface Modification and Pore Size Regulation of MSN as Function Aflibercept Carrier for Anti-Vascular Migration

Age-related macular degeneration (AMD) represents a leading cause of irreversible blindness in the elderly, primarily by choroidal neovascularization (CNV) leakage. While intravitreal injections of anti-angiogenic antibodies (e.g., aflibercept) provide clinical benefits, their short half-life necessitates frequent administrations, potentially causing ocular infections or retinal detachment. There is an urgent need for effective antibody delivery systems. Mesoporous silica nanoparticles (MSN) have emerged as promising nanocarriers due to their tunable porosity, surface modifiability, and biocompatibility, though their application in ophthalmology for antibody delivery remains underexplored. We developed two MSN carries: spiky mesoporous silica nanospheres (S-MSN) without amino groups and amine-functionalized hollow dendritic mesoporous silica nanospheres (A-HDMSN). Characterization revealed that A-HDMSN exhibited superior properties, including a larger surface area (550.32 vs. 257.72 m²/g), larger mesoporous pore size (17 vs. <10 nm), and 5.28 times higher drug loading capacity (286.31 ± 8.14 vs. 54.26 ± 3.61 μg/mg) compared to S-MSN (n = 3, p < 0.001), attributable to pore size effects and hydrogen bonding. FITC-labeled A-HDMSN demonstrated efficient uptake by retinal pigment epithelial cells (ARPE-19). Notably, A-HDMSN loaded with Aflibercept (A-HDMSN@Afl) showed significant inhibitory effect on VEGF-induced cell migration even 10 days after drug release in vitro, indicating a favorable sustained-release effect of the drug. These findings highlight A-HDMSN as a promising antibody delivery platform that could extend clinical dosing intervals, offering potential for improved AMD management.

VEGF; age-related macular degeneration; choroidal neovascularization; long-acting therapeutic effect; mesoporous silica.