Specific interaction through functional group and molecularly imprint-based QCM-D sensor for detection of phorate and malathion

Abstract

The molecularly imprinted polymer (MIP) is used to detect organophosphate pesticides phorate and malathion. The sol-gel technique is used to synthesize the MIP using 3- (trimethoxysilyl) propyl methacrylate (TMSPMA) as a functional monomer. We have coated the silica crystal of the quartz crystal microbalance (QCM) sensor with the synthesized MIP to detect the pesticides. The detection is based on the specific high adsorption for template molecule from solution. The real-time adsorption studies of the pesticides on MIP surfaces show their significant binding with the respective pesticide used as a template molecule. However, the adsorbed mass of the pesticides on the MIP of the pesticides is verified by using the concentration depletion method. The concentration of the pesticides was measured using high-performance liquid chromatography. The adsorption data matches well with the data obtained using QCM. The specificity and repeatability experiments indicate that the developed MIP is highly selective for the studied pesticides. The obtained selectivity of malathion and phorate are 9.4 and 6.8, respectively, and indicative of the goodness of the developed material.