Highlights

Nano-chitosan (CS) capped gold nanoparticles (CS-AuNPs) were prepared.

The synthesized CS-AuNPs were polydispersed with good stability.

CS-AuNPs showed significant DPPH and ABTS radical scavenging activities.

CS-AuNPs displayed promising inhibitory activity against diabetic related enzymes

CS-AuNPs showed great antitumor activity against LN229 cells.

Abstract

The present work synthesized nano-chitosan capped gold nanoparticles (CS-AuNPs) and tested its bioactivities. The fourier-transform infrared spectroscopy (FTIR) exhibited glucosamine group revealed the capping of chitosan in CS-AuNPs. The X-ray photoelectron spectroscopy (XPS) demonstrated the peaks at 84.49 eV and 88.49 eV was corresponding to gold. The dynamic light scattering (DLS) analysis indicated the size of 98.14 ± 6.62 nm, poly dispersion index (PDI) of 0.232 and zeta potential of 46.8 ± 2.07 mV for CS-AuNPs. The CS-AuNPs was exhibited the higher antioxidant, antibacterial and diabetes related enzyme inhibitory activities than that in CSNPs. The 50% of LN229 cell death was occurred through the treatment of 218.75 μg. mL⁻¹ and 500 μg. mL⁻¹ of CS-AuNPs and CSNPs respectively. The inhibitory concentration (IC₅₀) of CS-AuNPs showed higher cytotoxicity in LN229 via cellular damage, reactive oxygen species (ROS), and arresting about 42.33% cells in the G₁ phase. These results proved the multifunctional bioactive properties of CS-AuNPs.