膽紅素為人體血液之重要代謝物，而血液中之膽紅素濃度具有重要之臨床意義，血液中膽紅素濃度過高即表示肝臟功能出現異常。因此以分子模版高分子技術修飾於金電極表面，利用膽紅素進行氧化反應所產生之電流，成功製備出膽紅素之生物電化學感測器。
以AMPS (2-acrylamido-2-methylpropano-sulfonic acid) 螯合咪唑 (imidazole) 進行聚合反應後可使高分子材料兼具電子傳導與質子傳導之特性，可將膽紅素氧化所產生之質子傳導至高分子層外之溶液相，產生之電子則傳導至電極表面產生感應電流。因此於製備模版高分子電極時，選用AMPS螯合咪唑為功能性單體，選用交聯劑EGDMA (ethyl glycol dimethylacrylate) 進行自由基聚合，並加入模版分子膽紅素，形成模印膽紅素之imidazole-poly(AMPS-co-EGDMA)。
本文討論了多項製備過程之變因，包括有：聚合溫度與時間、交聯劑用量、聚合液體積等，亦討論感測之條件如：pH值與有機相之感測系統。尋找最佳製備條件時，以模版高分子電極之電化學感測為主，佐以SEM、AFM、FT-IR等定性儀器。於最佳製備條件下以SEM進行觀察，經修飾後之電極上可產生具多孔性之高分子薄膜，其膜厚約為3 m，AFM觀察之結果亦顯示MIP電極之表面粗糙度較高，高分子具較多之比表面積；利用FT-IR可觀察模版高分子內模印膽紅素之特徴吸收峰。
於電化學感測上，定電位I-t實驗結果顯示，MIP電極與NIP電極之膽紅素感測性比較可得約9.0之模印效果，且MIP電極對膽紅素之感測性可達約 3.6 A/cm2/mg/dL，電極之感測極限約為1.7 ppm，且電極不僅在pH=12.5之水溶液具最佳感測性，且於DMSO溶劑中亦可有效感測膽紅素濃度。此外，本實驗也進行以膽綠素為相似物之選擇性測試與膽紅素混合血清之干擾測試，選擇性測試實驗中MIP電極具有約3.1之選擇性，表現優於裸金電極與NIP電極；於血清干擾測試中，電極對膽紅素之感測性雖有下降，但仍可維持7.7左右之模印效果。

A bilirubin sensing electrode fabricated by molecularly imprinted polymer (MIP) has been successfully carried out. A functional monomer of 2-acrylamido-2-methylpropano-sulfonic acid (AMPS) chelated with imidazole was chosen because of their proton-electron conducting property and hydrogen-bond rich functional groups. A crosslinker ethyl glycol dimethylacrylate (EGDMA) was also added to strengthen the mechanical property of the polymer matrix. The molecularly imprinted imidazole-poly(AMPS-co-EGDMA) could generate specific cavities and better affinity to bilirubin. Bilirubin was thus attracted into the polymer matrix and the oxidation took place. The released protons could be transferred by imidazole to bulk solution phase and the electrons could be transferred to the gold surface. As a result, electrical signals could be detected.
The polymer surface morphology observation was done by SEM, AFM and FT-IR. From SEM and AFM, the MIP fabricated electrode could generate a porous polymer matrix and higher sensing surface area can be obtained. The film thickness was around 3 m. Different factors affecting the sensing as well as the imprinting effects were investigated. Under the optimal condition, an imprinted factor of 9.0 could be achieved. The sensitivity toward bilirubin was about 3.6 A/cm/mg/dL and the limit of detection is 1.7 ppm. A selectivity of 3.1 could be obtained in the biliverdin analogue test. Serum interference test were also done for further real sample detection. A fairly good imprinted factor of 7.7 could be gained. Therefore, the feasibility of the electrochemical detection of bilirubin caused from the proton-electron conducting mechanism via the imprinted imidazole-poly (AMPS-co-EGDMA) was confirmed.

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