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Abstract：
The selection of an appropriate transducer is a key element in biosensor development. Currently, a wide variety of substrates and working electrode materials utilizing different fabrication techniques are used in the field of biosensors. In the frame of this study, the following three specific material configurations with gold-finish layers were investigated regarding their efficacy to be used as electrochemical (EC) biosensors: (I) a silicone-based sensor substrate with a layer configuration of 50 nm SiO/50 nm SiN/100 nm Au/30-50 nm WTi/140 nm SiO/bulk Si); (II) polyethylene naphthalate (PEN) with a gold inkjet-printed layer; and (III) polyethylene terephthalate (PET) with a screen-printed gold layer. Electrodes were characterized using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) to evaluate their performance as electrochemical transducers in an aptamer-based biosensor for the detection of cardiac troponin I using the redox molecule hexacyanoferrade/hexacyaniferrade (K3[Fe (CN)6]/K4[Fe (CN)6]. Baseline signals were obtained from clean electrodes after a specific cleaning procedure and after functionalization with the thiolate cardiac troponin I aptamers \"Tro4\" and \"Tro6\". With the goal of improving the PEN-based and PET-based performance, sintered PEN-based samples and PET-based samples with a carbon or silver layer under the gold were studied. The effect of a high number of immobilized aptamers will be tested in further work using the PEN-based sample. In this study, the charge-transfer resistance (Rct), anodic peak height (Ipa), cathodic peak height (Ipc) and peak separation (∆E) were determined. The PEN-based electrodes demonstrated better biosensor properties such as lower initial Rct values, a greater change in Rct after the immobilization of the Tro4 aptamer on its surface, higher Ipc and Ipa values and lower ∆E, which correlated with a higher number of immobilized aptamers compared with the other two types of samples functionalized using the same procedure.
摘要：
选择合适的换能器是生物传感器开发中的关键因素。目前,在生物传感器领域中使用了利用不同制造技术的各种各样的基底和工作电极材料。在这项研究的框架内，研究了以下三种具有金饰面层的特定材料配置作为电化学（EC）生物传感器的功效：（I）具有50nmSiO/50nmSiN/100nmAu/30-50nmWTi/140nmSiO/bulkSi）层配置的基于有机硅的传感器基板；（II）具有金喷墨印刷层的聚萘二甲酸乙二醇酯（PEN）；（III）具有金喷墨印刷层使用电化学阻抗谱（EIS）和循环伏安法（CV）表征电极，以评估其在基于适体的生物传感器中作为电化学换能器的性能，该生物传感器用于使用氧化还原分子六氰基环/六氰基环(K3[Fe（CN）6]/K4[Fe（CN）6]。在特定的清洁程序之后以及在用硫醇盐心脏肌钙蛋白I适体“Tro4”和“Tro6”功能化之后，从清洁电极获得基线信号。以改善基于PEN和基于PET的性能为目标，研究了烧结的PEN基样品和在金下具有碳或银层的PET基样品。将在使用基于PEN的样品的进一步工作中测试大量固定化适体的效果。在这项研究中,电荷转移电阻(Rct)，阳极峰高（Ipa），测定了阴极峰高(Ipc)和峰间距(ΔE)。基于PEN的电极表现出更好的生物传感器特性，例如较低的初始Rct值，将Tro4适体固定在其表面后，Rct的变化更大，较高的Ipc和Ipa值和较低的ΔE，与使用相同程序官能化的其他两种类型的样品相比，这与更高数量的固定化适体相关。
