Synthesis Of Theophylline Molecules Imprinted Polymer Beads And Their Molecular Recognition Property

Molecular imprinted technology (MIT) is a new and potential separation technique and is receiving extensive attention in some areas. In this thesis, progress on synthetic method and technology of molecular imprinting polymers (MIPs) were reviewed. As a kind of artificial molecular recognition materials, its applications in biomimic sensors, solid phase extraction, and enzyme minic catalyst and so on were also summarized in detail.The contents of this thesis include the three following aspects:(1) Molecularly imprinted P-cyclodextrin polymers (MI-CDPs) were prepared using theophylline as a template, P-cyclodextrin as a functional monomer and toluene-2,4-diisocyanate as a crosslinker. Then, MI-CDPs powder was embedded with crosslinked polyvinyl alcohol by an inverse suspension polymerization method, and spheric MI-CDPs absorbent was prepared. The synthesis conditions of spheric MI-CDPs were optimized and their adsorption properties were investigated with a static adsorption method.(2) Molecularly imprinted polymers beads (MIP beads) were prepared using theophylline as a template, methacrylic acid as a functional monomer by suspension polymerization. The factors influencing the adsorption capacity of spheric MI resin were studied, such as crosslinking degree, crosslinker and its amount, porogen and adsorption media. Adsorption isotherms were obtained with static adsorption method. Isosteric adsorption enthalpy, adsorption free energy and adsorption entropy were calculated according to the relationship ofthermodynamic function. Isosteric adsorption enthalpy was between 29 kJ-mol"1 ~ 34 kJ'mol"1, which reveals that the main molecularly recognition interaction is hydrogen bonding. Then, the Scatchard analysis showed that the molecularly imprinted polymers beads using methacrylic acid as functional monomer could form two kinds of non-equivalent binding sites. The dissociation constants of spheric MI resin were estimated to be Kdi=1.032X lO^mol-L1 and ^=9.434 X 10^ moNL1. The most apparent calculated adsorption capacities were about <2maxi= 37.997 umol'g'1 and (2max2=186.557nmol?g"1, respectively. At last, the influence of adsorption media on spheric MI resin adsorption selectivity was studied.(3) The molecularly imprinted interpenetrating polymer network (MI-IPN) composed of macroporous polydivinyl benzene resin and polydivinyl benzene were synthesized using theophylline as template molecule using a sequential method. Adsorption isotherms were obtained with static adsorption method, and the results indicated that the MI-IPN have preferable molecule recognition performance. The Scatchard analysis also showed that the MI-IPN using theophylline as template molecule exists two kinds of recognition sites, their dissociation constants were estimated to be K