分子辨識 (Molecular recognition) 是臨床上免疫分析的基礎，使用生物抗體作為分子辨識元件具有優異的辨識效果，但是生物抗體的種種不穩定性造成分析上廣受限制。分子模版高分子 (molecularly imprinted polymer, MIP) 是一種擬生物抗體的方式，利用合成出對適當模版分子具有辨識能力的高分子進行分析。此方法是將模版分子與功能性單體溶於適當溶劑中，經由聚合產生穩定的複合物型態，最後以適當溶劑將模版分子洗出，便形成對模版分子具有優異親和力和構形相互補的辨識基座，此辨識基座即為分子模版高分子。
　　本研究以臨床上診斷腎臟疾病的重要指標分子，肌酸酐 (creatinine) 做為模版分子，使用鋅原紫質 (zinc(II) protoporphyrin) 與甲基丙烯酸 (methacrylic acid) 作為功能性單體，製備肌酸酐模版高分子。鋅原紫質具有 Lewis 酸鍵結位址，在模印過程中，肌酸酐模版分子可與鋅原紫質上的鋅原子產生可逆的配位鍵結。此外，鋅原紫質為一螢光單體，其激發波長為 423 nm，放射波長大約為 590 nm。
　　利用鋅原紫質與甲基丙烯酸共聚合製備之肌酸酐模版高分子在單一肌酸酐溶液之模印因子 (imprinting factor) 為 5.24 ± 0.02；在肌酸酐、肌酸 (creatine) (共存物)、N-羥基丁二醯亞氨(N-hydroxysuccinimide) (相似物) 及咯烷酮 (2-pyrrolidinone) (相似物) 共存之雙成份與三成份溶液進行選擇性吸附實驗，所得對肌酸酐最佳的選擇率 (selectivity ratio) 分別為 10.57 ± 2.43 與 3.39 ± 0.61。比較使用鋅原紫質與甲基丙烯酸共聚合、單一鋅原紫質聚合與單一甲基丙烯酸聚合而得之肌酸酐模版高分子，由實驗結果可知，使用鋅原紫質與甲基丙烯酸共聚合製備之肌酸酐模版高分子對肌酸酐具有較佳的辨識能力。以不同比例之鋅原紫質與甲基丙烯酸製備之模版高分子對肌酸酐之吸附為：降低鋅原紫質與甲基丙烯酸之含量製備而得之肌酸酐模版高分子對肌酸酐的選擇率並無提升；相同比例之鋅原紫質與甲基丙烯酸但提高聚合溫度製備而得之肌酸酐模版高分子對肌酸酐的吸附量增加，但是選擇率卻較不穩定。另外，使用鋅原紫質的螢光性質進行螢光感測，由實驗結果可知，鋅原紫質與甲基丙烯酸共聚合製備之肌酸酐模版高分子的螢光強度會隨著肌酸酐濃度增加而降低。

　Molecular recognition between guest and host is the base of clinical immunoassay. To utilize biological element as molecular recognition unit possess good recognition efficiency, but it was restricted in assay environment by its unstable property. Molecularly imprinted polymer is an approach using artificial material as biomimetic antibody. Molecularly imprinted polymer is synthesized using functional monomers to copolymerize to cross-linking agent in the presence of template molecule. After the polymerization, the template molecule is washed out by proper solvent so that binding site possess specific affinity and complementary structure with template molecule was formed.
　In this study, creatinine was chosen as the template molecule because of its importance as a clinical index for the kidney function. The functional monomers, zinc(II) protoporphyrin (ZnPP) and methacrylic acid (MAA) were used in polymerization. ZnPP having a Lewis acid binding site zinc, for the imprinting process the template molecule creatinine is reversibly coordinated to the zinc atom. And ZnPP is a fluorescent functional monomer, its excited wavelength is 423 nm and emission wavelength is around 590 nm.
　Molecularly imprinted polymer which copolymerized using both ZnPP and MAA to recognize creatinine was named poly(ZnPP-co-MAA). From the experimental results of poly(ZnPP-co-MAA), the imprinting factor was 5.24 ± 0.02. Creatinine and other compounds, creatine, N-hydroxysuccinimide and 2-pyrrolidinone, were used to comprise mixture solutions for specific adsorption experiment. In the adsorption results from mixtures, the best selectivity ratio for creatinine by poly(ZnPP-co-MAA) in binary and ternary solutions were 10.57 ± 2.43 and 3.39 ± 0.61, respectively. In addition to poly(ZnPP-co-MAA), molecularly imprinted polymer polymerized using only ZnPP or MAA, named poly(ZnPP) and poly(MAA) as references. Comparison of there different polymer, poly(ZnPP-co-MAA) possess good imprinted effect and specificity was performed. From the results of using different ratio of ZnPP and MAA copolymerize in the same condition, decrease amount of ZnPP and MAA can not promote the selectivity ratio to creatinine; from the results of using the same ratio of ZnPP and MAA copolymerize in different condition, arise the polymeric temperature can increase the binding capacity but no obvious promotion to selectivity ratio. From the results of fluorescence measurement of poly(ZnPP-co-MAA), fluorescence intensity of the poly(ZnPP-co-MAA) decreased with creatinine concentration was achieved.

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