| The photonic crystal technology is one of the rapid development high-techs in recent years. This paper focuses on the core of the photonic crystal technology. The study aims at preparing superior optical properties of photonic crystals and describing their characteristics, detecting harmful substances in food through the modification or introduction of other technologies, and laying the foundation for the promotion of their applications in direction of rapid and field testing. The specific contents are as follows:1. SiO2template opal photonic crystals (PC) was prepared using the vertical deposition method, and the polymethyl methacrylate (PMAA) photonic crystal was obtained by polymerization of acrylic acid (MAA) pre-polymerzation and subsequent removal the template. We studied the response of PMAA PC to several common matrix factors. Results show that pH has little effect on PC, while temperature, ethanol content and salt concentration make the reflection peak of the PC changing. So we should pay attention to these aspects in the application of PC. The carboxyl group of the PMMA PC was activated by EDC method. Contrast the response of PMAA PC to drugs whose molecular structure contents amino before and after activation. This broadens the scope of application of PMAA PC and helps to screening of the unknown samples.2. The molecular imprinting technology was introduced into the PC technology. The target molecular was added into the pre-polymerization solution, and the molecular imprinted photonic crystals (MIPC) were obtained. Affection of template PC to sensitivity and specificity of the MIPP was studied; proportion of functional monomer and cross-linking agent in pre-polymerization was optimized. The elution conditions were also optimized through comparing the MIPC color and reflection peak before and after eluting. Three kinds of molecules (chloramphenicol, bisphenol A, diethylstilbestrol) MIPC were prepared and the conditions for the adsorption were optimized. Comparison the adsorption of MIPC to these several drugs, we found that the chloramphenicol (CAP) imprinted PC has better adsorption to CAP than other MIPC to specific drugs. This provides the basis for the establishing of CAP MIPC sensor and application.3. The CAP MIPC sensor was constructed and used to detect CAP using a label-free method. Different CAP MIPC were prepared with three different solvents, and their adsorption effect to CAP was detected and compared. Results show that the methanol-based MIPC has the best adsorption to CAP. We also watched the adsorption of non-imprinted PC (NIPC) to CAP, and proved that the imprinting is the major factor of MIPC adsorption. The methanol-based CAP MIPC has good adsorption to CAP, and certain adsorption to the structure analogue of CAP, but merely adsorption to non-structure analogues of CAP. The response time and reusability were studied. Results show that the CAP MIPC sensor has short response time and high reusability. In current work, we successfully prepared the MIPC to detect CAP for the first time. Response style performance for the peak intensity decreased and the detection range was1ng/ml-1000ng/ml.In summary, we successfully prepared the PMMA inverse opal photonic crystal,optimized the preparation condition and detected molecules with amino group. We also prepared the CAP MIPC by combination of photonic crystal and molecular imprinted technology. The MIPC was of short response time, reusable and high specifical. All these researches would lay the foundation for the application of photonic crystal technology. |
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