The Preparation Of Acetylsalicylic Acid Molecularly Imprinted Polymer And Its Performance & Application In Detection

Objective: A novel effective and practical method was established by MIT for analyzing aspirin (Asp) in the complex samples, and a new method was presented for washing template from MIPs. The imprinting and recognizing principle of MIP was studied by IR from molecule level. It provided theoretical evidences for seeking appropriate template and functional monomer from imprinting technique.Method: In this paper, the imprinting of Asp was studied. The Asp-MIPs were prepared by three methods such as conventional bulk polymerization, sacrificial silica-gel polymerization and in-situ polymerization. The physical and chemical properties of the polymers were analyzed by scanning electron microscope (SEM), IR, Ultraviolet (UV) HPLC technology. Adsorption isotherms, static adsorption ability of MIPs for Asp were measured by UV. The results of Scatchard analysis showed that MIPs prepared in this thesis adsorbed their templates. Ultrasonic extraction was applied to wash template to optimize the means of washing.Results:1. Asp-MIPs which had special molecule recognition ability to Asp were synthesized, taking Asp as a template by conventional bulk polymerization. In the procedure, MAA and AM were selected as functional monomer, respectively. 1,4-Divinyl benzene (DVB) as crosslinker. It showed there were two different binding sites in the Asp-MIPs, and P(AAsp) was stronger and better binding ability with Asp than P(MAsp).There were no significant differences between the results of the Asp tablet by Asp-MIPs and the pharmacopoeia method.2. A series of Asp-MIPs taking AM and 4-VP as functional monomer were synthesized after the polymerization procedure was optimized with silica-gel as sacrificial materials. The amount of the porogen was optimized. The result showed that the binding ability of MIPs was improved with the increasing amount of porogen in a certain range. The special molecule recognition ability of MIP from the characteristic radicel was verified by IR anlysis. The results showed by Scatchard analysis: there were two different binding sites in MIPs in the process of the adsorption substrate, and no sites in NMIP. The SEM showed that MIP prepared by sacrificial silica-gel polymerization had larger surface area and regular particle shape than that by conventional bulk polymerization.3. The Asp imprinted monolithic series were prepared by in-situ polymerization when AM was selected as functional monomers, DVB as crosslinker. Main factors which influenced on the MIP's absorption ability were discussed detailedly such as the system of porogen and the reaction time. The SEM showed that there were apertures in the imprinted monolithic columns which enabled the mobile phase flow in lower pressure. The chromatogram results showed that the Asp imprinted monolithic columns had special molecule recognition ability to Asp. Conclusion: Asp-MIPs were applied to the complex samples triumphantly and provided a convenient path for the selective enrichment and separation in real samples and blood samples. AM was a better functional monomer; Sacrificial silica-gel polymerization was better than conventional bulk polymerization; The polymerization procedure was simpler by in-situ polymerization, but the effect of Asp imprinted monolithic columns was lower; Ultrasonic distill was a high effect washing mothed. It was effective that the recognizing principle and the predicting theory of MIP from molecule level by IR.