Study On Piezoelectric Sensor Technology For The Detection Of Endosulfan Using Molecularly Imprinted Polymer As Recognition Elements

Molecularly imprinted polymers (MIPs) are polymers prepared in presence of a template that serves as a mould for the formation of template-complementary binding sites. Thus, MIPs can be created to recognize a target molecule with affinity and selectivity comparable to natural receptors and were called as "artificial antibody". And these materials can withstand much harsher conditions than antibodies, such as high temperature, pressure, extreme pH, and organic solvents. These properties have made them extremely attractive for solving problems in the fields of preparative chemical separations, purification and sensors, or for the removal of specific molecular targets from complex mixtures.In this article, traditional precipitation polymerization was investigated in order to obtaine desired uniform microspheres. Endosulfan was used as templates to synthesize the molecularly imprinted polymers. The environmental scanning microscopy was used to describe the shape and the size of the obtained polymer microspheres, the results showed that the uniform, global nano-metric imprinted polymer microspheres were obtained, the size of the reaulted microspheres ranged from 200nm to 300nm.It was studied that the endosulfan imprinted polymer microspheres was fixed on the quartz crystal electrode to fabricate the piezoelectric sensor, in this study the PVC and THF were used as embed pigment and solvent, respectively. The surface of the MIP microspheres coated quartz crystal electrodes was demonstrated by atomic force microscopy (AFM), the results showed that the distribution of the MIP microspheres is uniform. The detection conditions were optimized to analyze the real samples, The sensor developed exhibits a liner relationship between the frequency shift and endosulfan concentration in the range of 10 to 1000ng/mL (y= 6.21+0.133), and the detection limit was 13.22 ng/mL., But there are many environmental factors affecting the detection results, so further work was need to do to perfect the resulted sensor.From above, this study gives me some help in theory and practice to realize the real time, on-spot, fast detection of and the samples preparation prior to analysis pesticide in foodstuff.