Collaborative Innovation Center of Tumor Marker Detection Technology, Equipment and Diagnosis-Therapy Integration in Universities of Shandong, Shandong Province Key Laboratory of Detection Technology for Tumor Makers, School of Chemistry and Chemical Engineering, Linyi University, Feixian Campus, Linyi, 273400, People's Republic of China.
Industrial Chemistry Department, Dagon University, Yangon Region, 11421, Myanmar.
Mikrochim Acta. 2019 Jul 19;186(8):550. doi: 10.1007/s00604-019-3662-8.
A pH-responsive superwettable chip is described whose surface can switch between superhydrophobic and superhydrophilic. It can be used for the visual detection of the prostate specific antigen (PSA) based on contact angle readout. Magnetic beads were modified with primary antibody against PSA. After immunobinding, gold nanoparticles loaded with secondary antibody labeled with glucose oxidase is added. On addition of glucose, gluconic acid is formed which causes a drop in the local pH value. This results in a wettability switch of the pH-responsive superwettable chip from hydrophobic to hydrophilic. Under the optimized conditions, PSA can be quantified with a 3.2 pg mL limit of detection by analyzing the contact angle and the related color that changes from blue via orange to red. The method is applicable to PSA detection in serum samples and for visual classification by cancer patients and healthy persons. It is also suitable for color-blind and color-weak individuals. Conceivably, this kind of assay can be transferred to the determination of various kinds of other bioanalytes including nucleotide, proteins, and even of ions and small organic molecules, and thus is has a wide scope. Graphical abstract Schematic presentation of a pH-responsive superwettable chip coated with silica nanoparticles for the visual detection of prostate specific antigen (PSA) by reading the contact angle. The superwettable chip achieves reliable clinical detection of serum PSA from prostate cancer patients.
一种 pH 响应超润湿性芯片被描述，其表面可以在超疏水和超亲水之间切换。它可以用于基于接触角读数的前列腺特异性抗原 (PSA) 的可视化检测。磁珠用针对 PSA 的一抗修饰。免疫结合后，加入负载有与葡萄糖氧化酶标记的二抗的金纳米粒子。加入葡萄糖后，形成葡萄糖酸，导致局部 pH 值下降。这导致 pH 响应超润湿性芯片的润湿性从疏水切换到亲水。在优化条件下，通过分析接触角和相关颜色（从蓝色变为橙色再变为红色），可以以 3.2 pg mL 的检测限定量检测 PSA。该方法适用于血清样品中 PSA 的检测以及癌症患者和健康人的可视化分类。它也适用于色盲和色弱者。可以想象，这种测定方法可以转移到包括核苷酸、蛋白质甚至离子和小分子等各种其他生物分析物的测定中，因此具有广泛的应用范围。
