膽紅素 (Bilirubin)，為人體血紅蛋白代謝產物之一，大部分膽紅素來自於衰老紅血球中血紅素的分解代謝，而血紅素的濃度可反映肝功能是否異常。因此血清中膽紅素的濃度常是作為判斷肝臟疾病的重要生理指標。
本研究是以分子模印 (molecular imprinting) 技術，結合室溫離子液體 (room-temperature ionic liquid, RTIL)，以發展具特異性吸附，且具有電化學感電性之膽紅素模版高分子薄膜，以此製備對膽紅素具專一性的電流式感測電極，並進行相關探討。
混摻室溫離子液體混摻之模版高分子 (room-temperature ionic liquid doped molecularly imprinting polymer, RTIL-MIP) 薄膜修飾電極之製備，乃是以膽紅素為模版分子，以單體methacrylic acid (MAA) 與交聯劑 ethylene glycol dimethylacrylate (EGDMA)，搭配1-butyl-3-methylimidazolium bis(trifluoro-methylsulfonyl)imide ([BMIM][Tf2N]) 室溫離子液體，在 2,2-azo-bis-isobutyronitrile (AIBN) 起始劑 作用下，進行熱聚合，於金電極表面形成膽紅素模版高分子薄膜，經SEM影像觀察可知，薄膜厚度相當均勻；平均厚度約為1.98 ± 0.03 μm。經萃洗移除膽紅素，此高分子薄膜表面即可留下對膽紅素分子具辨識性之孔洞 (cavity)。因膽紅素在適當電位下，具有電化學反應活性，因此就可利用電流感測方式分析其濃度。
本研究亦探討膽紅素感測訊號與模印因子 (imprinting factor) 之關係及影響模印效果之變數。RTILs有助於提升模版高分子電極之感測訊號，且此電極在低濃度膽紅素範圍下 (0.2 ~ 1.0 mg/dL) 具有相當好的模印效果，模印因子可達5.52 ± 0.09，靈敏度為0.367 ± 0.019 μA/cm2/mg/dL。而RTIL-MIP電極在膽綠素共存下對膽紅素之選擇性約為2.13 ± 0.02。在干擾性測試中，儘管在小牛血清的環境下，仍可偵測出膽紅素，且靈敏度與未添加膽紅素時差異不大，證實本實驗所製備的RTIL-MIP電極具有抗血清干擾的能力。

Bilirubin is the metabolite of human hemoglobin. The concentration of bilirubin in serum is often regarded as an important physiological indicator of liver diseases.
The electrochemical sensing of bilirubin was developed the molecularly imprinted polymer film modified electrode doped with room-temperature ionic liquids (RTILs) is investigation of fabricated in this work for the specific binding and electrochemical properties.
For the preparation of the imprinted polymer, bilirubin was the template molecule, by using molecular imprinting methacrylic acid (MAA) and ethylene glycol dimethylacrylate (EGDMA) were used as functional monomer and cross-linker, respectively. RTIL, 1-butyl-3-methylimidazolium bis(trifluoro-methylsulfonyl)imide ([BMIM][TF2N]) for the synthesis of bilirubin imprinted polymer film by heated polymerization in the presence of the initiator 2,2-azo-bis-isobutyronitrile (AIBN). The scanning electron microscopic image show that the imprinted polymer film thus synthesized was rather uniform and the average thickness was approximate 1.98 ± 0.03 m。After extraction, a large portion of bilirubin templates was removed. Therefore, the polymer film would be left with cavity specific for the binding of bilirubin. Via which, the electrochemical detection of bilirubin could be possible to carry out.
In summary, RTILs may improve the signals of the MIP electrodes. The imprinting factor of 5.52 ± 0.09 and the sensitivity of 0.367 ± 0.019 μA/cm2/mg/dL cound be achieved at the low concentration range (0.2-1.0 mg/dL) from the RTIL-MIP electrode fabricated in this work. The selectivity of bilirubin against biliverdin is 2.13 ± 0.02. For interference test, bilirubin was further detected by the RTIL-MIP electrode in the presence of bovine calf serum (BCS) and the sensitivity was nearly the same as the background to background of water. Thus, it confirms the RTIL-MIP electrode may avoid the interference from serum. The results indicate the feasibility of using the RTIL-MIP electrode for the detection of bilirubin in serum.

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