The results indicate the advantages of using CHS to produce blood-compatible GNPs with antioxidant, cytotoxic, and electrochemical properties.

GNPs were synthesized using CHS, and their physicochemical properties were evaluated. The antibacterial activity of CHS-GNPs was estimated against both gram-positive and gram-negative bacteria. The cytotoxicity of CHS and CHS-GNPs was obtained by MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) test, and the electrocatalytic activity of CHS-GNPs was investigated. The blood compatibility was evaluated by the in vitro hemolysis assay.

The absorption band at 527 nm reveals the reduction of Au3+ into GNPs. The transmission electron microscopy (TEM) image displays the spherical shape of GNPs in the range of 5.8-31.4 nm. The CHS and CHS-GNPs at 300 µg/mL revealed a maximum DPPH (1, 1-diphenyl-2-picrylhydrazyl) scavenging activity of 73% and 65%, respectively. CHS-GNPs showed antibacterial activity against Bacillus subtilis , while CHS has no antibacterial activity. CHS-GNPs exhibited a cytotoxicity effect against MDA-MB-468 and βTC3 cancer cell lines, and the electrochemical study indicated a significant increase in electrocatalytic properties of CHS-GNPs coated electrode compared by the bare electrode. The hemolysis test proved the blood compatibility of CHS-GNPs.