Size-dependent cellular uptake and sustained drug release of PLGA particles

Poly (lactic-co-glycolic) acid (PLGA) particles have become a commonly used drug delivery strategy in the pharmaceutical industry. In this work, we aim to investigate the size-dependent cellular internalization of PLGA particles and its effects on sustained drug release. We prepared three different-sized particles using PLGA (200, 500 and 2000 nm) ranging from submicrometer to micrometer. Dexamethasone (DEX) with excellent anti-inflammatory properties was used as a model drug to prepare DEX-loaded PLGA particles (DPs). We comprehensively investigated the encapsulation efficiency, cellular uptake and in vitro drug release profile. Pharmacodynamic assessment revealed that, in the lipopolysaccharide (LPS)-induced RAW 264.7 cells model, 500 nm DPs showed sustained anti-inflammatory efficacy. This work provides important information for designing PLGA-based drug delivery systems for biomedical applications.