Layered construction of nano immuno-hybrid embedded MOF as an electrochemical sensor for rapid quantification of total pesticides load in vegetable extract

The present attempt reports a novel electrochemical immuno-sensor (BSA/Chi-AuNP-rIgG-BSA/MOF/ITO) based on the concatenation of polyclonal antibody (rIgG) based nano immuno-hybrid (Chi-AuNP-rIgG-BSA) with MOF modified ITO substrate (MOF/ITO) for the detection of a wide range of pesticides (pyrethroid, neonicotinoid, and organophosphates) with few exceptions (hexaconazole and profenofos). The primary layer for the screening of various pesticides by MOF-5 via structural porosity and polar functional groups is underpinned by the following layer of nano immuno-hybrid (Chi-AuNP-rIgG-BSA) for signal amplification. Molecular docking methods were used to give an insight of interactions between the rIgG in nano immuno-hybrid and the pesticides. The developed BSA/Chi-AuNP-rIgG-BSA/MOF/ITO platform can measure total pesticide load using cyclic voltammetry at 0.410 V in solution of [Fe (CN)6]3-/4- mediator in phosphate buffer saline within a linear range of 4 to 100 ngL-1(R2 = 0.92) and a sensitivity of (25.4 μAng-1Lcm-2) by a single calibration curve. Further, it has been tested for spiked as well as real (field) sample vegetable extract with minimum deviation (