Chen Lizhen, Wang Naixiang, Wu Jie, Yan Feng, Ju Huangxian
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China.
Department of Physics, The Hong Kong Polytechnic University, Hong Kong.
Anal Chim Acta. 2020 Sep 1;1128:231-237. doi: 10.1016/j.aca.2020.07.006. Epub 2020 Jul 13.
Sialic acid usually locates at the terminal of glycoproteins and glycolipids on cell surface. Compared to normal cells, cancer cells generally express much more sialic acid residues, and the sialylation of cell surface proteins or lipids is related to the progression of tumors, which leads to high expression of serum sialic acid in cancer patients. This work used an organic electrochemical transistor as the sensing platform to design a simple and suitable device for sensitive and convenient detection of sialic acid level in serum samples. The transistor-based biosensor consisted of three typical drain/source/gate Au electrodes on a glass substrate and a polymer membrane to serve as conducting channel between source electrode and drain electrode. The gate electrode was modified with carboxylated multi-wall carbon nanotubes to covalently bind 3-aminobenzeneboronic acid, which specifically recognized sialic acid to change the effect gate voltage of the transistor, and thus produced the signal of drain-source channel current for sensitive detection of sialic acid ranging from 0.1 to 7 mM. The novel biosensor possessed excellent specificity for distinguishing normal and cancer people. The detection results of serum samples from lung cancer patients demonstrated the excellent performance of the transistor-based biosensor, showing the potential application in clinical diagnose.
唾液酸通常位于细胞表面糖蛋白和糖脂的末端。与正常细胞相比，癌细胞通常表达更多的唾液酸残基，并且细胞表面蛋白或脂质的唾液酸化与肿瘤进展相关，这导致癌症患者血清唾液酸高表达。这项工作使用有机电化学晶体管作为传感平台，设计了一种简单且合适的装置，用于灵敏便捷地检测血清样本中的唾液酸水平。基于晶体管的生物传感器由玻璃基板上的三个典型漏极/源极/栅极金电极以及用作源电极和漏电极之间导电通道的聚合物膜组成。栅电极用羧基化多壁碳纳米管修饰，以共价结合3-氨基苯硼酸，其特异性识别唾液酸以改变晶体管的有效栅极电压，从而产生漏源通道电流信号，用于灵敏检测0.1至7 mM范围内的唾液酸。这种新型生物传感器在区分正常人和癌症患者方面具有出色的特异性。肺癌患者血清样本的检测结果证明了基于晶体管的生物传感器的优异性能，显示出其在临床诊断中的潜在应用。
