School of Materials Science, Japan Advanced Institute of Science and Technology (JAIST) 1-1 Asahidai, Nomi City, Ishikawa, 923-1292, Japan.
Talanta. 2011 Oct 15;85(5):2576-80. doi: 10.1016/j.talanta.2011.08.018. Epub 2011 Aug 16.
In this work, a sensitive label-free impedimetric hCG-immunosensor was constructed by using a commercial screen-printing carbon ink electrode (namely disposable electrochemical printed chip) as the basis. The carbon ink electrode of DEP chip is modified first by deposition of polypyrrole-pyrole-2-carboxylic acid copolymer and thence hCG antibody immobilization via the COOH groups of pyrrole-2-carboxylic acid, which can serve as a linker for covalent biomolecular immobilization. The experimental results exposed that the designed immunosensor is more sensitive than other previously reported immunosensors, in the case of detection limit and linear range for antigen detection. With optimal fabrication parameters, the detection limit for α-hCG was 2.3 pg/mL in 10mM phosphate buffer saline (PBS) solution containing 1% bovine serum albumine (BSA). Moreover, the use of inexpensive DEP chip as a basis for these immunosensors will allow for simple instrumentation, disposable and portable at low cost. This work also demonstrates a new approach to develop a sensitive and label-free impedimetric immunosensor based on screen-printed electrode for applications in clinical diagnosis.
在这项工作中，我们构建了一种灵敏的无标记阻抗 hCG 免疫传感器，使用商业丝网印刷碳油墨电极（即一次性电化学印刷芯片）作为基础。DEP 芯片的碳油墨电极首先通过聚吡咯-吡咯-2-羧酸共聚物的沉积进行修饰，然后通过吡咯-2-羧酸的 COOH 基团将 hCG 抗体固定，这可以作为共价生物分子固定的连接物。实验结果表明，与其他先前报道的免疫传感器相比，设计的免疫传感器在检测限和抗原检测的线性范围方面更为敏感。在最佳的制造参数下，在含有 1%牛血清白蛋白（BSA）的 10mM 磷酸盐缓冲盐水（PBS）溶液中，α-hCG 的检测限为 2.3pg/mL。此外，使用廉价的 DEP 芯片作为这些免疫传感器的基础，可以实现简单的仪器设备，具有一次性、便携性和低成本的特点。这项工作还展示了一种新的方法，基于丝网印刷电极开发灵敏的无标记阻抗免疫传感器，可应用于临床诊断。
