Optimized Detection to Organophosphorous Pesticide by Selecting the Most Appropriate Nano-Size of Sensing Nano-Material

This paper reports an optimal sensing nanomaterial of mesoporous-silica SBA-15 for detecting residual organophosphorous (OP) pesticide by selecting appropriate wall-thickness of the amorphous-SiO₂ nano-channels to optimize the interaction activity of the surface ≡Si-OH with P=O in OP molecules. With the different-sized SBA-15 nanomaterials loaded at the free ends of resonant-cantilevers, optimization for the sensing-materials can be in situ implemented by using the resonant-cantilevers themselves. After directly detecting OP molecules to evaluate the response curves, a novel physicochemical-parameter extraction method is developed to quantitatively obtain the value of adsorption isosteric heat ( Qst) that is used as an essential criterion to select the best sensing-material with appropriate nano-wall thickness. With the novel method, we have successfully obtained the optimal sensing nanomaterial for the pesticide of dichlorvos (DDVP).