Summary: | 碩士 === 國立臺灣大學 === 化學工程學研究所 === 91 === In this work, a molecularly imprinted polymer (MIP) of morphine (MO) was prepared through thermal radical copolymerization of methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) in the presence of MO templates. And a molecularly imprinted sorbent assay (MIA) based on a colorimetric label was developed to determine the adsorption isotherm of MO-MIP binding.
In practice, the MO-bound MIP was brought into contact with an aqueous mixture of Fe3+ and [Fe(CN)6]3- so that the 3-phenolic group of MO was oxidized and then Fe3+ was reduced to Fe2+. As a result, the MO-bound MIP was labeled with Prussian blue (PB), which was attributed to the instant co-precipitation of Fe2+ and [Fe(CN)6]3- (Ksp = 10-40). Accordingly, MO-MIP binding of the blue dye could be detected by visible spectroscopy. In addition, such labeling could successfully distinguish MO from codeine. Upon data analyses, a two-site binding isotherm with two dissociation constants of 6.00 × 10-5 M and 1.03 × 10-3 M was found for MO-MIP binding. MIAs for non-MIP were also performed. In addition, the results of flow-system characterizations and the particle size effect are also described in this study.
Moreover, molecular recognition sites for morphine (MO) were imprinted on methacrylic acid (MAA)- trimethylolpropane (TRIM) copolymer particles. The imprinted particles were immobilized on Au piezoelectric quartz crystals by the electro-polymerization of pyrrole. After the template was extracted from the polymer particles, bound amounts of the MO-imprinted polymer were evaluated using a 9-MHz quartz crystal microbalance (QCM). As a MO-imprinted polymer attached to the QCM was immersed into a MO solution, the QCM frequency decreased and then was saturated at a constant frequency. We demonstrate the recognition characteristics of MO-imprinted polymers by comparing the frequency change of imprinted with that of non-imprinted polymers. It was observed that a significant difference in the decrease in frequency was shown between imprinted and non-imprinted polymers. This means that the MO-imprinted polymer has a good ability to recognize MO molecules. Also, the selectivity of the MO-imprinted polymers was investigated by using MO-analogous molecules, such as morphine-3β-D-glucuronide and nalorphine.
With the above finding, this thesis not only depicts a successful fabrication for MO-imprinted polymer particles but also apply the particles in the flow system, immunoassay and the modification of QCM electrode. These applications can be used in the determination of the properties of molecularly imprinted polymers and will possibly promote the development of the molecular imprinting micro-sensing chip (MIMSC), which add value to this study.
|