Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Antimicrobial Resistance Integrated Research Group, Singapore-MIT Alliance for Research and Technology, 1 CREATE Way, Singapore 138602, Singapore.
ACS Appl Mater Interfaces. 2021 Dec 8;13(48):57962-57970. doi: 10.1021/acsami.1c17589. Epub 2021 Nov 19.
Catalytic redox reactions have been employed to enhance colorimetric biodetection signals in point-of-care diagnostic tests, while their time-sensitive visual readouts may increase the risk of false results. To address this issue, we developed a dual photocatalyst signal amplification strategy that can be controlled by a fixed light dose, achieving time-independent colorimetric biodetection in paper-based tests. In this method, target-associated methylene blue (MB) photocatalytically amplifies the concentration of eosin Y by oxidizing deactivated eosin Y (EYH) under red light, followed by photopolymerization with eosin Y autocatalysis under green light to generate visible hydrogels. Using the insights from mechanistic studies on MB-sensitized photo-oxidation of EYH, we improved the photocatalytic efficiency of MB by suppressing its degradation. Lastly, we characterized 100- to 500-fold enhancement in sensitivity obtained from MB-specific eosin Y amplification, highlighting the advantages of using dual photocatalyst signal amplification.
催化氧化还原反应已被用于增强即时诊断测试中的比色生物检测信号，但其对时间敏感的目视读数可能会增加假阳性结果的风险。为了解决这个问题，我们开发了一种双光催化剂信号放大策略，该策略可以通过固定光剂量来控制，从而实现基于纸张的测试中与时间无关的比色生物检测。在该方法中，与靶标相关的亚甲蓝 (MB) 在红光下通过氧化失活的曙红 Y (EYH) 来催化放大曙红 Y 的浓度，然后在绿光下用光引发剂与曙红 Y 自催化聚合生成可见水凝胶。通过对 MB 敏化 EYH 光氧化的机理研究，我们抑制了 MB 的降解，从而提高了 MB 的光催化效率。最后，我们从 MB 特异性曙红 Y 放大中得到了 100 到 500 倍的灵敏度增强，突出了使用双光催化剂信号放大的优势。
