With the imminent needs of rapid, accurate, simple point-of-care systems for global healthcare industry, electrochemical biosensors have been widely developed owing to their cost-effectiveness and simple instrumentation. However, typical electrochemical biosensors for direct analysis of proteins in the human biological sample still suffer from complex biosensor fabrication, lack of general method, limited sensitivity, and matrix-caused biofouling effect. To resolve these challenges, we developed a general electrochemical sensing strategy based on a designed steric hindrance effect on an antibody surface layer. This strategy utilizes the interaction pattern of protein-G and immunoglobulin G (Fc and Fab regions), providing a steric hindrance effect during the target capturing process. The provided steric hindrance effect minimizes the matrix effect-caused fouling surface and altered the path of electron transfer, delivering a low-fouling and high-sensitivity detection of protein in complex matrices. Also, an enzyme-based horseradish peroxidase/hydroquinone/H2O2 transduction system can also be applied to the system, demonstrating the versatility of this sensing strategy for general electrochemical sensing applications. We demonstrated this platform through the detection of Tau protein and programming death ligand 1 with a subpico molar detection limit within 10 min, satisfying the clinical point-of-care requirements for rapid turnaround time and ultrasensitivity.

中文翻译：

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基于免疫球蛋白G的立体障碍分析法，用于蛋白质检测。

随着全球医疗行业对快速，准确，简单的即时医疗系统的迫切需求，电化学生物传感器因其成本效益和简单的仪器仪表而得到了广泛的发展。然而，用于直接分析人类生物样品中蛋白质的典型电化学生物传感器仍然遭受复杂的生物传感器制造，缺乏通用方法，灵敏度有限以及基质引起的生物污染效应的困扰。为了解决这些挑战，我们基于对抗体表面层的设计位阻效应，开发了一种通用的电化学传感策略。该策略利用了蛋白G和免疫球蛋白G（Fc和Fab区域）的相互作用模式，在靶标捕获过程中提供了位阻效应。所提供的位阻效应最大程度地减少了由基质效应引起的结垢表面，并改变了电子转移的路径，从而实现了复杂基质中蛋白质的低结垢和高灵敏度检测。同样，基于酶的辣根过氧化物酶/氢醌/ H2O2转导系统也可以应用于该系统，这证明了该传感策略在通用电化学传感应用中的多功能性。我们通过检测Tau蛋白和对死亡配体1进行编程，并在10分钟内达到亚皮摩尔检测极限，从而证明了该平台，满足了快速更换时间和超敏性的临床即时医疗要求。基于酶的辣根过氧化物酶/对苯二酚/ H2O2转导系统也可以应用于该系统，证明了该传感策略在通用电化学传感应用中的多功能性。我们通过检测Tau蛋白和对死亡配体1进行编程，并在10分钟内达到亚皮摩尔检测极限，从而证明了该平台，满足了快速更换时间和超敏性的临床即时医疗要求。基于酶的辣根过氧化物酶/对苯二酚/ H2O2转导系统也可以应用于该系统，证明了该传感策略在通用电化学传感应用中的多功能性。我们通过检测Tau蛋白和对死亡配体1进行编程，并在10分钟内达到亚皮摩尔检测极限，从而证明了该平台，满足了快速更换时间和超敏性的临床即时医疗要求。