Stimulated Drug Release to Human Melanoma Cell Line Using NIR-responsive PLGA Microparticles.

Stimulated on-demand drug release is critical in treating melanoma, enabling targeted therapeutic interventions with enhanced efficacy and minimized side effects. Poly(lactic-co- glycolic acid) (PLGA) microparticles (MPs) fabricated using the emulsion method provide a cost-effective biocompatible pathway towards developing a drug release system for such treatments. Near-infrared (NIR)-responsive particles such as indocyanine green (ICG) and silver nanoparticles (AgNPs) have been incorpo- rated for generating an on-demand release system. Characteriza- tion results showed that the MPs were around 20 microns in size. Cytotoxicity assay results show that the heat generated from ICG is slightly harmful to cells but not sufficient. There was a need for the exposure of NIR light to the PLGA-ICG/AgNp's-DTIC MPs to cause a detrimental effect on the attached A375 cells. MPs containing NIR-responsive materials without the stimulation of NIR light were harmful, but the natural diffusion release was too low to kill the cells entirely within an exposure time of 24 hours. In the future, to ensure that there is negligible release without light, MPs will either be coated with peptide sequences for specific targeting or with other biodegradable materials. Emulsion-fabricated PLGA MPs, incorporating NIR-responsive agents, offer a promising pathway for on-demand drug release, exemplified by drug-incorporated particles with good entrapment efficiency and minimal cytotoxicity, paving the way for targeted melanoma treatment.