Application of Forsskaolea tenacissima mediated gold nanoparticles in dyes discolouration, antibiotics removal, and metal ions detection

Abstract

• Synthesis of F. tenacissima aqueous and ethanolic extracts mediated AuNPs. • Catalytic properties of the synthesized AuNPs in dyes degradation/reduction. • Antibiotics removal by synthesized AuNPs from tap and river water samples. • Metal ions sensing by synthesized AuNPs in tap and river water samples. Synthesis of nanoparticles using plant extract is environment-friendly, cost-effective, and sustainable. This study reports the synthesis of aqueous and ethanolic extracts mediated gold nanoparticles of aerial parts of F. tenacissima (FTAAuNPs) using chloroauric acid. The synthesized nanoparticles obtained from aqueous and ethanolic extracts under sunlight in 1:15 and 1:10 ratios with localized surface plasmon resonance (LSPR) peaks at 533 nm exhibited sizes of 15.7 nm and 27.6 nm, respectively, as revealed by scanning electron, transmission electron, and atomic force microscopic (SEM, TEM, AFM) techniques. Sharp intense surface plasmon resonance (SPR) peaks were obtained at basic pH (8 to 11), however, the same peaks broadened and reduced at elevated temperatures. FTAAuNPs demonstrated an efficient removal (>80%) of dyes such as methylene blue (70%), Congo red (80%), methyl orange (82%), Rhodamine B (50%), ortho -nitrophenol (85%) and para -nitrophenols (85%), and antibiotics (amoxicillin, levofloxacin, doxycycline) up to 90%. Furthermore, FTAAuNPs were successfully used for sensing of Pb ++ , Cu ++ , Ni ++ , and Zn ++ ions in tap and river water samples. Hence, this study offers simple, cost effective, and efficient removal of pollutants/hazards in the water samples, and could solve water and sanitation problems especially in Pakistan.