NER: Protein-Based Nanobiosensors for Environmental Monitoring

该奖项支持基于CdSe荧光的电子转移猝灭的新型纳米生物传感器的开发工作。这种传感器将基于具有已知荧光特性的CdSe纳米粒子，这些纳米粒子与已知的对小分子具有高度特异性亲和力的蛋白质在化学上联系在一起。纳米颗粒上蛋白质的存在将减少（淬灭）这种颗粒通常表现出的强荧光。所关注的小分子的结合有望改变蛋白质结构，并导致荧光猝灭的减少或消除。计划中的研究旨在开发麦芽糖传感器，基于革兰氏阴性菌周围质间隙中发现的麦芽糖结合蛋白，以及基于金属离子结合转录因子家族的两个成员（分别为ArsR和CadC）的亚砷酸盐/锑酸盐和Pb2+/Cd2+。这些新型传感器将属于一类纳米生物传感器，通常被称为无试剂纳米生物传感器，因为它们不需要除传感器本身以外的试剂。过去，这种单组分传感器采用寡核苷酸来提供检测感兴趣分子所需的特异性。然而，寡核苷酸的使用限制了可以检测的目标分子的范围。现有的基于蛋白质的传感器具有潜在的更大范围，需要多种组件，这使得它们的使用变得复杂。除了这种无试剂纳米生物传感器的潜在用途外，该项目还将为研究生提供研究培训，并将为底特律公立学校学生的暑期项目中的新活动提供基础。

This award supports efforts to develop a new class of nanobiosensors based on electron transfer quenching of CdSe fluorescence. The sensors will be based on CdSe nanoparticles of known fluorescence properties to which proteins with known, highly specific affinities for small molecules have been linked chemically. Presence of the protein on the nanoparticle will reduce (quench) the strong fluorescence normally exhibited by such particles. The binding of the small molecule of interest is expected to alter protein structure and result in the reduction or elimination of the quenching of the fluorescence. The planned studies are aimed at development of sensors for maltose, based on the maltose binding protein found in the periplasmic space of gram-negative bacteria, and for arsenite/antimonite and Pb2+/Cd2+, based on two members of a family of metal ion binding transcription factors (ArsR and CadC, respectively). These novel sensors will belong to a class of nanobiosensors usually termed reagentless nanobiosensors because they do not require reagents other than the sensor itself. In the past, such single component sensors have employed oligonucleotides to provide specificity needed for the detection of the molecule of interest. However, use of oligonucleotides limits the range of target molecules that can be detected. Existing protein-based sensors, which have a potentially larger range, require multiple components, which complicates their use. In addition to the potential utility of such reagentless nanobiosensors, the project will provide research training for graduate students, and will provide the basis for new activities in a summer program for students in the Detroit public schools.