Facile and cost-effective optical sensing of abamectin and ivermectin using gold nanoparticles conjugated with organosilicon compound and on cellulose filter paper

This study presents a novel, facile, and low-cost method for the separation and sensing of two closely related antiparasitic drugs, abamectin (ABM) and ivermectin (IVM), which have significant applications in agriculture and medicine. The aim was to explore the potential of gold nanoparticles (Au NPs) conjugated with organosilicon compounds as effective optical sensors for these drugs. However, existing methods often involve complex procedures and excessive costs. The aim of this study is to develop a novel, facile, and low-cost method for the separation and sensing of abamectin and ivermectin by exploring the potential of gold nanoparticles (Au NPs) conjugated with organosilicon compounds as effective optical sensors for these drugs. Au NPs were extracellular photosynthesized using yeast extract and conjugated with 1-naphthol-based organosilicon compound (Naph-1-TBDPS) to form Au NP/Naph-1-TBDPS nano-photoactive composite. In addition, the application of the developed nanosensor on cellulose filter paper was achieved. The interaction of abamectin or ivermectin with the nanocomposite (nanosensor) was investigated using UV–Vis spectroscopy. Abamectin caused a red shift in the spectral line of the ABM/Au NPs/Naph-1-TBDPS nanocomposite, while ivermectin caused a blue shift of IVM/Au NPs/Naph-1-TBDPS nanocomposite, indicating distinct interactions. The mechanistic pathway of the observed phenomenon was explained by the formation of a silyl-based abamectin complex in the C22–C23 bond and the etching of Au NPs in the presence of ivermectin forming Au clusters. It was determined that the difference in spectral shifts enabled the selective detection of abamectin and ivermectin. For the first time, this study presents a novel and cost-effective method for the identification and sensing of ABM and IVM using the Au NPs/organosilicon composite. The method demonstrated high sensitivity and selectivity, offering potential for practical applications in drug analysis and quality control, thereby addressing the limitations of previous methods that often-involved complex procedures and high costs.