Physicochemical characterization and preliminary in vitro antioxidant activities of curcumin and meloxicam co-encapsulated PLGA nanoparticles

Abstract

Nanoformulations (NFs) are suitable for encapsulation and delivery of multiple hydrophobic drugs. Polymers enable higher drug entrapment and sustained drug release profile. In this study, poly(lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) co-encapsulating hydrophobic agents including curcumin (Cur) and meloxicam (Mlx) were prepared and physicochemically characterized. Mono and dual drug loaded NPs of Cur and Mlx were synthesized using singleemulsion (o/w) solvent evaporation method. NPs were characterized for zeta size and potential, polydispersity index (PDI), encapsulation efficiency, in vitro drug release and storage stability. In vitro antioxidant activity was determined using DPPH and ABTS scavenging assays. Spherical smooth surfaced mono and dual drug-loaded NPs showed particle sizes of 104.2 to 195.4 nm, zeta potential of -22.9 to -17.1 mV and PDI below 0.25. High encapsulation efficiency (>75%) of all drug-loaded NPs was found. NPs exhibited an initial burst following sustained drug release rates at pH 7.4. In vitro, Cur and Mlx co-loaded NPs exhibited higher radical scavenging activity compared to pure drugs in DPPH and ABTS assays. Storage stability studies showed insignificant changes in NPs at 4°C and 27°C for one month. Conclusively, Cur and Mlx co-encapsulation resulted in stable NFs with high drug encapsulation efficiencies, improved drug release profiles and antioxidant activities.