Takeda Kouta, Kusuoka Ryo, Inukai Misaki, Igarashi Kiyohiko, Ohno Hiroyuki, Nakamura Nobuhumi
Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo, 184-8588, Japan.
Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8657, Japan; Protein Discovery and Engineering Team, VTT Technical Research Center of Finland Ltd., FI-02044 VTT, Espoo, Finland.
Biosens Bioelectron. 2021 Feb 15;174:112831. doi: 10.1016/j.bios.2020.112831. Epub 2020 Nov 20.
Quantitative routine detection of fucose, which is a cancer marker, in urine is effective for the preliminary screening of cancer. Amperometric biosensing methods have the advantage of being simple, rapid, and precise for urinalysis. However, coexisting electroactive interferences such as ascorbic acid (AA), dopamine (DA), and uric acid (UA) prevent accurate measurements. In this work, an amperometric l-fucose biosensor unaffected by interferences was developed and utilizes direct electron transfer type bioelectrocatalysis of pyrroloquinoline quinone (PQQ)-dependent pyranose dehydrogenase from Coprinopsis cinerea (CcPDH). The isolated PQQ domain from CcPDH was immobilized on gold nanoparticle (AuNP)-modified electrodes, which obtained a catalytic current at a lower potential than the oxidation potential of the interfering compounds. Applying an operating potential of -0.1 V vs. Ag|AgCl (3 M NaCl) enabled the detection of l-fucose while completely eliminating the oxidation of AA, DA, and UA on the electrodes. The increase in the specific area of the electrodes by increasing the AuNP drop-casting time resulted in an improvement in the sensor performance. The biosensor exhibited a linear range for l-fucose detection between 0.1 mM and 1 mM (R = 0.9996), including a cut-off value, the sensitivity was 3.12 ± 0.05 μA mM cm, and the detection limit was 13.6 μM at a signal-to-noise ratio of three. The biosensor can be used to quantify the concentration of l-fucose at physiological levels and does not require urine preprocessing, making it applicable to practical use for point-of-care testing with urine.
尿液中岩藻糖（一种癌症标志物）的定量常规检测对癌症的初步筛查有效。安培生物传感方法在尿液分析中具有简单、快速和精确的优点。然而，诸如抗坏血酸（AA）、多巴胺（DA）和尿酸（UA）等共存的电活性干扰物会妨碍准确测量。在这项工作中，开发了一种不受干扰影响的安培型L-岩藻糖生物传感器，该传感器利用来自灰盖鬼伞（CcPDH）的吡咯喹啉醌（PQQ）依赖性吡喃糖脱氢酶的直接电子转移型生物电催化作用。从CcPDH分离出的PQQ结构域固定在金纳米颗粒（AuNP）修饰的电极上，该电极在比干扰化合物氧化电位更低的电位下获得催化电流。施加相对于Ag|AgCl（3M NaCl）为 -0.1V的工作电位能够检测L-岩藻糖，同时完全消除电极上AA、DA和UA的氧化。通过增加AuNP滴铸时间来增加电极的比表面积，从而提高了传感器性能。该生物传感器对L-岩藻糖检测的线性范围为0.1mM至1mM（R = 0.9996），包括一个临界值，灵敏度为3.12±0.05μA mM cm，在信噪比为3时检测限为13.6μM。该生物传感器可用于定量生理水平的L-岩藻糖浓度，并且不需要尿液预处理，使其适用于尿液即时检测的实际应用。
