Application Of Molecular Imprinting And Related Technoligies On The Molecular Recognition Of Tridimenol And Myclobutanil

Molecular imprinting is a technique to prepare polymers with recognition sites having a predetermined selectivity for given molecules. Much more attention has been paid to this technique in recent years. Molecularly imprinted polymers (MIPs) have been applied to chrornatographic stationary phase, artificial antibodies, catalysts, sensors and drug assay tools. In this thesis, A molecular template synthetic polymer highly selective for triadimenol (myclobutanil) was prepared by molecular imprinting technique (MIT) and have been used as HPLC stationary phases. The binding capacity was studied by equilibrium binding test Effects of mobile phase composition on retention and separation factor were investigated. There are three chapters in this thesis.In Chapter I, the principle of MIT, polymerization methods, application of this technique and its future developments were introduced.In Chapter II, A molecular imprinting polymer particular effect for triadimenol was prepared by molecular imprinting technique. Its binding and selectivity to triadimenol were evaluated by batch adsorption experiments. Triadimenol-imprinted polymer exhibited higher affinity to triadimenol compared to non-imprinted polymer, Scatchard analysis indicated that the imprinted polymer using methacrylic acid (MAA) as functional monomer could form two kinds of binding sites by noncovalent interactions . The multiple-sites binding model was used to calculate the maximum number of binding sites and dissociation constants. The dissociation constants were estimated to be 2.80×10~-4mol/L and 9.71×10~-3 mol/L .The selective binding experiment for substrates indicated that the polymer gave much higher affinity and selectivity for triadimenol than analogues.In Chapter III, myclobutanil has been employed as templates for the preparation of in-situ molecularly imprinted polymer rods for use as liquid chromatographic stationary phases. The preparation procedure was simple and easy. The recognition of the molecularly imprinted polymer rod was evaluated by comparing the retention values of myclobutanil and its analogues. The mixture of the two close analogues, myclobutanil and paclobutrazol can be baseline separated when the mobile solution is composed of methanol:water=4:6. Effects of acetic acid mobile phase composition on retention were investigated. Molecular recognition mechanism of myclobutanil-imprintedpolymer was proposed. The results indicated that hydrogenolysis effect dominated retention mechanism in no polarity media as well as shape recognition.