蛋白质在固态纳米孔中的易位行为

The Translocation Behavior of Proteins through Solid Nanopores

纳米孔是目前单分子检测的一项重要技术。除了DNA,蛋白质也成为纳米孔研究的重点对象。作者以血清蛋白为例,研究了蛋白质在氮化硅纳米孔中的易位行为,并对蛋白质的易位事件进行了分析。和DNA相比,蛋白质本身的荷电和结构特性,使其进入纳米孔的通量较低,同时,蛋白质和纳米孔表面存在吸附现象,减慢了蛋白质在纳米孔中的易位速度。当电压增大时,蛋白质的易位事件增加,过孔速度加快,吸附现象减弱。不过,在高电压下,蛋白质在电场力的拉扯下构象发生变化,出现部分或者全部解折叠。这些结果表明纳米孔提供了一个独特的获得蛋白质结构和功能信息的检测平台,可为蛋白质相关疾病的诊断和治疗提供技术支持。

The nanopore has become an important tool for single molecule detection. Besides DNA, proteins have become important targets of nanopore sensors. Taking serum albumin as an example in this work, protein translocation through solid nanopores was measured and the translocation events were characterized by the nanopore sensor. Compared with DNA, lower throughput of nanopores for protein sensing was observed depending on the distinct charge and structural profiles of the protein. And the translocation velocity decreased as a result of non-specific adsorption interaction between the protein and nanopores. As voltages increased, the capture rates were enhanced, protein transtocation was accelerated and the protein absorption phenomenons were suppressed. However, the protein structure was disrupted by the enhanced electrical force at high voltages. These results show that the nanopore provides an unique testing platform for protein structure and function, which is helpful for diagnosis and treatment of the protein related diseases.