Screen-printed electrodes as impedimetric immunosensors for the detection of anti-transglutaminase antibodies in human sera
Screen-printed electrodes as impedimetric immunosensors for the detection of anti-transglutaminase antibodies in human sera
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DOI：
10.1016/j.aca.2007.06.041
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发表时间：
2007-07-30
影响因子：
6.2
通讯作者：
Lisdat, F.
中科院分区：
文献类型：
--
作者：
Balkenhohl, T.;Lisdat, F.
人血清抗转谷氨酰胺酶抗体浓度是诊断乳糜泻的重要分析指标。本文研制了一种用于电化学检测人血清中抗谷氨酰胺酶抗体的免疫传感器。该免疫传感器是基于将谷氨酰胺转氨酶固定在丝网印刷的金电极上，金电极上覆盖有聚（4-苯乙烯磺酸钠）聚电解质层。通过扩增步骤评估抗原-抗体相互作用：用过氧化物酶（POD）标记的免疫球蛋白孵育，随后用3-氨基-9-乙基咔唑（AEC）进行生物催化氧化。利用电化学阻抗谱（EIS）测定了传感器电极界面性能的变化。阻抗谱可以拟合到含有恒相元件（CPE）的Randles等效电路中。此外，阻抗测量可以通过仅在两个选定的频率上执行EIS来简化，而不会损失可靠性。这些一次性免疫传感器芯片与不同浓度的抗谷氨酰胺酶抗体孵育后，其电荷转移阻力（R-ct）发生了变化。从而建立标定图。最后，利用免疫传感器对不同人血清IgG和IgA型抗谷氨酰胺酶自身抗体浓度进行表征。(c) 2007 Elsevier B.V.版权所有
The concentration of anti-transglutaminase antibodies in human sera is an important analytical marker for the diagnosis of the autoimmune disorder celiac disease. In this work, an immunosensor for the electrochemical detection of anti-transglutaminase antibodies in human sera was developed. The immunosensor is based on the immobilization of transglutaminase onto screen-printed gold electrodes which were covered with a polyelectrolyte layer of poly (sodium-4-styrensulfonic acid). The antigen-antibody interaction was evaluated using an amplification step: incubation with peroxidase (POD)-labeled immunoglobulins and subsequent biocatalytic oxidation of 3-amino-9-ethylcarbazole (AEC). Changes in the interfacial properties of the sensor electrode were determined by electrochemical impedance spectroscopy (EIS). Impedance spectra could be fitted to a Randles equivalent circuit containing a constant phase element (CPE). Furthermore, it was shown that impedance measurements could be simplified by performing EIS at only two selected frequencies, without loss of reliability. Incubation of these disposable immunosensor chips with various anti-transglutaminase antibody concentrations resulted in changes in their charge transfer resistance (R-ct). Thereby, a calibration graph could be established. Finally, immunosensors were used for characterizing different human sera with respect to their anti-transglutaminase autoantibody concentration of the IgG and IgA type. (c) 2007 Elsevier B.V. All rights reserved.