Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; The Graduate School, Chiang Mai University, Chiang Mai 50200, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand.
National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani 12120, Thailand.
Colloids Surf B Biointerfaces. 2022 Feb;210:112260. doi: 10.1016/j.colsurfb.2021.112260. Epub 2021 Dec 5.
A dual-mode electrochemical biosensor is successfully developed for simultaneous detection of two different kinds of breast cancer biomarkers, namely cancer antigen 15-3 (CA 15-3) and microRNA-21 (miRNA-21), for the first time. The sensor composes of a poly(3-aminobenzylamine)/two-dimensional (2D) molybdenum selenide/graphene oxide nanocomposite modified two-screen-printed carbon electrode array (dual electrode), functionalized individually with 2,3-diaminophenazine-gold nanoparticles and toluidine blue-gold nanoparticles. Both kinds of the redox probe-gold nanoparticles are employed as signaling molecules and supports for immobilization of anti-CA 15-3 antibodies and capture DNA-21 probes, respectively. Due to the good conductivity and high surface-to-volume ratio of the nanocomposite, high amount of the antibodies and capture probes can be immobilized on the modified dual-electrode, giving the efficient duplex detection. Consequently, the biosensor provides good selectivity, and high sensitivity for the dual target analyte detection. The experimental results show that this label-free biosensor exhibits good linear responses to the concentrations of both target analytes with the limits of detection (LODs) of 0.14 U mL and 1.2 fM for CA 15-3 and miRNA-21, respectively. This assay strategy has a great potential to be further developed for the simultaneous detection of a variety of miRNAs and protein biomarkers for point-of-care (POC) diagnostic applications.
首次成功开发了一种双模式电化学生物传感器，用于同时检测两种不同类型的乳腺癌生物标志物，即癌抗原 15-3（CA 15-3）和 microRNA-21（miRNA-21）。该传感器由聚（3-氨基苄胺）/二维（2D）二硒化钼/氧化石墨烯纳米复合材料修饰的双丝网印刷碳电极阵列（双电极）组成，分别用 2,3-二氨基吩嗪-金纳米粒子和甲苯胺蓝-金纳米粒子功能化。两种类型的氧化还原探针-金纳米粒子均用作信号分子，并分别作为固定 CA 15-3 抗体和捕获 DNA-21 探针的支撑物。由于纳米复合材料具有良好的导电性和高的表面积与体积比，可以在修饰的双电极上固定大量的抗体和捕获探针，从而实现高效的双目标物检测。因此，该生物传感器对双靶标分析物的检测具有良好的选择性和高灵敏度。实验结果表明，这种无标记生物传感器对两种目标分析物的浓度表现出良好的线性响应，CA 15-3 和 miRNA-21 的检测限（LOD）分别为 0.14 U mL 和 1.2 fM。这种分析策略具有很大的潜力，可以进一步发展用于即时诊断应用中多种 miRNA 和蛋白质生物标志物的同时检测。
