Junlapak Nuttakorn, Khumngern Suntisak, Nontipichet Natha, Kangkamano Tawatchai, Thavarungkul Panote, Lomae Atchara, Bejrananda Tanan, Numnuam Apon
Center of Excellence for Trace Analysis and Biosensor, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Division of Physical Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Center of Excellence Innovation in Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand.
Center of Excellence for Trace Analysis and Biosensor, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand.
Bioelectrochemistry. 2026 Feb;167:109074. doi: 10.1016/j.bioelechem.2025.109074. Epub 2025 Aug 5.
A highly sensitive and selective label-free electrochemical immunosensor was developed to detect nuclear matrix protein 22 (NMP22), a bladder cancer marker, in urine. A screen-printed carbon electrode (SPCE) was modified with carboxylate graphene-supported thionine (Thi@Gr-COOH) as a redox probe, and a unique structure of ordered mesoporous carbon decorated with gold nanoparticles (AuNPs@OMC). The large active site and uniform porosity of OMC facilitated the deposition of AuNPs, significantly increasing the antibody coverage. NMP22 concentration was determined based on changes in the peak current of Thi reduction measured by differential pulse voltammetry before and after the formation of the immunocomplex. In the optimal condition, the proposed immunosensor demonstrated linearity of 1.0 × 10 to 1.0 × 10 ng mL with detection limit of 2.96 × 10 ng mL. Furthermore, the proposed sensor demonstrated good reproducibility, stability for over 20 days, reusability up to 5 cycles of binding and regeneration, and good selectivity. The developed electrochemical immunosensor effectively detected NMP22 in human urine samples, achieving good recoveries and results that matched the NMP22™ Bladderchek™ TEST, proving it can be used effectively.
开发了一种高灵敏度、高选择性的无标记电化学免疫传感器，用于检测尿液中的膀胱癌标志物核基质蛋白22（NMP22）。用羧酸盐石墨烯负载的硫堇（Thi@Gr-COOH）作为氧化还原探针修饰丝网印刷碳电极（SPCE），并制备了一种独特结构的金纳米颗粒修饰的有序介孔碳（AuNPs@OMC）。有序介孔碳的大活性位点和均匀孔隙率促进了金纳米颗粒的沉积，显著增加了抗体覆盖率。根据免疫复合物形成前后差分脉冲伏安法测量的硫堇还原峰电流变化来测定NMP22浓度。在最佳条件下，所提出的免疫传感器线性范围为1.0×10至1.0×10 ng mL，检测限为2.96×10 ng mL。此外，该传感器具有良好的重现性、超过20天的稳定性、高达5次结合和再生循环的可重复使用性以及良好的选择性。所开发的电化学免疫传感器有效地检测了人尿液样本中的NMP22，回收率良好，结果与NMP22™ Bladderchek™ TEST匹配，证明其可有效应用。
