Synthesis and characterization of small-sized gold nanoparticles coated by bovine serum albumin (BSA) for cancer photothermal therapy

In the present study, small gold nanoparticles <5 nm coated with natural protein Bovine Serum Albumin (BSA) was synthesized and characterized using UV–vis spectrophotometer, Dynamic Light Scattering (DLS), Transmission Electron Microscopy (TEM), zeta potential and scanning electron microscopy (SEM). Three types of cancer cell lines; Rhabdomyosarcoma (RD), Murine fibroblast (L20B) and RAW 264.7 monocyte-macrophage (MQ) were tested and treated by photothermal strategy, in vitro, by conjugating BSA-AuNPs complex of (0.125, 0.25, 0.5 and 1 mg/ml) concentrations with continuous low power laser irradiation, green (532 nm) and near-infrared (NIR) (800 nm) at 0.5, 1, 2 and 3 min, separately. Cytotoxicity effect was determined by MTT assay. The vital impact of photothermal technique has investigated at 1 mg/ml and 3 min irradiation period as identified in RD cell line in comparison with other types; where cytotoxicity more than 74% was reached. Prominent results were demonstrated in the green and NIR region by pH -induced aggregation effect of small nanoparticles inside the cancer cells, which make the small-sized BSA-AuNPs are promising agents for cancer photothermal therapy.