A highly sensitive β-AKBA-Ag-based fluorescent “turn off” chemosensor for rapid detection of abamectin in tomatoes

Abstract

This study presents the synthesis of a sensitive AKBA-Based fluorescent “Turn off” chemosensor for rapid detection of abamectin residues in tomatoes. Silver nanoparticles were synthesized by using 3-O-acetyl-11-keto-β-boswellic acid (β-AKBA) by chemical reduction method. The characterization of AKBA-AgNPs was performed by UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). The average particle size of NPs was found to be 46.2 ± 2 nm with lumps of macro-sized particles. TEM data further revealed that nanoparticles were polydispersed and spherical in shape and also show good stability at high temperatures and pH. The biosensing properties of nanoparticles were studied for the detection of abamectin residues in tomato samples. Abamectin a natural product derived from the bacterium Streptomyces avermitilis is effective against a wide range of pests. In sensing protocol 67 organic tomato samples were segregated into 34 (safe group, without a spray of abamectin) and 33 samples (as an unsafe group, sprayed with abamectin insecticide solution). Emission spectra of these sample solutions were measured in the wavelength range of 450–530 nm, excitation wavelength was fixed at 488 nm. The effect of minor wavelength variation for the discrimination and classification of the two groups was investigated by applying two chemometric methods including partial least square discriminant analysis and principal component analysis with projection. The mechanism of its interaction between the AKBA-Ag NPs and abamectin residue was also established through UV/visible, FTIR, and TEM microscopy. This newly synthesized nanoparticle was found to have excellent stability at variables, i.e., temperature, storage period, salt concentration, and pH. Therefore, the synthesized Ag NPs are potential candidates for biosensing applications against abamectin.