Role of solvent on fabrication of essential amino-acid based nanoparticles directed for photothermal therapy

Abstract

Nanoparticle-mediated targeted drug delivery has revolutionized nano-therapeutics. It ensures improved biodistribution, bioavailability and drug accumulation in targeted diseased locations inside the body. The right concentration of the drug and stability of the carrier are the major challenges for efficient targeted drug delivery. In this study, we have synthesized indocyanine green (ICG) loaded Poly-L-Lysine (PLL) nanoparticles by the two-step self-assembly process. Different solvents; phosphate-buffered saline (PBS), deionized water and Milli-Q water have been used to identify how the solvent selection affects the stability and encapsulation efficiency of the nanoparticles. The effect of solvent interaction on nanoparticles morphology, stability, and encapsulation efficiency was investigated using scanning electron microscopy (SEM), UV-visible spectroscopy, and fluorescence spectroscopy. The results demonstrated maximum loading, stability and nanoparticle formation in case of PBS buffer followed by deionized water and Milli-Q water respectively. The ICG-loaded PLL nanoparticles lying in the near-infrared therapeutic window were then tested for their cytotoxicity and photothermal efficiency.