Eco-friendly synthesis of gold nanoparticles using carboxymethylated gum Cochlospermum gossypium (CMGK) and their catalytic and antibacterial applications

Gold nanoparticles (AuNPs) were synthesized by the green method with activated Cochlospermum gossypium (carboxymethylated Cochlospermum gossypium gum or carboxymethylated gum kondagogu: CMGK) as stabilizer and reducing agent. The obtained size of AuNPs was 11 +/- 2nm. The impacts of HAuCl4 concentration, CMGK concentration, and reaction time on the synthesis of AuNPs were investigated. The techniques, UV-visible spectroscopy, FTIR, DLS, TEM, and powder XRD, were used for characterization. The reducing capacity of the synthesized CMGK-AuNPs was tested for reduction of 4-nitrophenol (4-NP) along with NaBH4. The effects of NaBH4, catalyst dose, and temperature were studied for reduction of 4-NP. The AuNPs showed good antibacterial activity against E. coli and Bacillus subtilis. The outcomes of the study indicated that CMGK-AuNPs have notable antimicrobial and environmental applications.