Anti-inflammatory drug releasing absorbable surgical sutures using poly(lactic-co-glycolic acid) particle carriers

The goal of the current study was to develop an absorbable surgical suture incorporating poly(lactic-co-glycolic acid) (PLGA) particles loaded with dexamethasone (DEX) as an anti-inflammatory drug. DEX-loaded PLGA (DEX/PLGA) particles, prepared using a water-in-oil emulsion method, were electrostatically immobilized onto the surface of absorbable sutures. The surfaces of these DEX/PLGA particles were coated with positively charged polyethyleneimine (PEI) molecules, which imparted a net positive surface charge. These modified PEI-coated DEX/PLGA (PEI/DEX/PLGA) particles were then immobilized on negatively charged absorbable suture surfaces by electrostatic attraction. The results showed that DEX was efficiently loaded into PLGA particles and that the surfaces of DEX/PLGA particles were successfully coated with PEI. PEI/DEX/PLGA particles were well dispersed and immobilized onto suture surfaces. In addition, PEI/DEX/PLGA particles remained adherent to suture surfaces in vitro and demonstrated sustained DEX release in phosphate-buffered saline (pH 7.4) at 37 °C for up to 28 days under static conditions. The tensile strength and elongation at break of PEI/DEX/PLGA particle-treated sutures were almost the same as that of non-treated control sutures. Findings of this study show that various therapeutic drugs could be efficiently incorporated into absorbable sutures using biodegradable polymeric particles, and suggest that the devised absorbable, drug-eluting, sutures offer a promising basis for a novel absorbable surgical suture system.