| Surface plasmon resonance (SPR) is a physical optical phenomenon which produced by using metal film optical coupling. Detection of molecular interactions can be achieved by real-time monitoring the SPR changes. SPR does not need any marker used as fluorescent and isotopic measurments can real-time measure, and it can also keep the activities of natural biological molecules. For an advantage, the analysis only needs a few minutes to wait, so SPR sensor will have broad application prospect.Molecular imprinting is a method that can prepare polymer material with predetermined selectivity towords a certain guest molecule. This technique derives from Fischer's lock-and-key hypothesis and Pauling's antibody-forming hypothesis initially. The selective recognition of molecularly imprinted polymers to the template molecules is obtained through the "memory effect" of the cavities formed during the polymerization process. Molecularly imprinted polymers have not only specific recognization like enzyme and antibody, but also other advantages like specific chemical and physical stability, long working life, simple preparation methods. Significant progresses have been received in the areas such as chiral separation, artifical antibody, sensing and catalysis.In this thesis, by combining the good performance of MIT such as high selectivity and good recognition with the high sensitivity and good response performance of SPR spectroscopy, we developed molecularly imprinted SPR sensors for acephate and 1H-indole-3-acetic acid.Based on surface-bound photo-radical initiator polymerization, the acephate-imprinted SPR sensor was prepared. Under the optimized experimental conditions, the SPR sensor has higher selective adsorption performance for the template acephate compared to other organophosphorus analogues. It was used for the determination of trace acephate in apple, canola, actual samples, and the satisfactory results were obtained.The method showed good recoveries and precision, 98.0% (RSD 1.9%) for apple, 96.6% (RSD 1.4%) for canola. Based on a signal to noise ratio of 3, the detection limits were 1.14×10-13 mol/L for apple sample and 4.29×10-14 mol/L for cole sample. The method showed good recoveries and precision for the apple and cole samples spiked with acephate solution.By the 2D molecularly imprinted self-assembly method, an IAA-imprinted SPR sensor was prepared. Under the optimized experimental conditions, the SPR sensor has higher response for the template IAA compared to the other plant hormones. The single SPR sensor decorated with the MIM was used to determine IAA concentrations in peach, Rosa flower and Crape myrtle bud, and satisfactory results were obtained. Based on a signal to noise ratio of 3, the detection limits were 2.3×10-13 mol/L for Crape myrtle, 2.0×10-13 mol/L for Peach and 3.2×10-13 mol/L for Rosa. The method showed good recoveries and precision, 95.7% (RSD 0.54%) for Peach, 98.1% (RSD 3.4%) for Rosa and 98.1% (RSD 2.5%) for Crape myrtle, spiked with 0.4171μg, respectively. These results suggest that a combination of SPR sensing and the MIM is a simple, promising alternative method for determining endogenous IAA in plant tissue in a real-time manner.
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