Charge Transfer Study of DNA/MoS2 interface

项目摘要 串联DNA重复序列(三核苷酸重复序列或TNR)的扩展导致超过50% 遗传可转移性疾病，每年影响400万人。当前最先进的技术 长度突变的基因检测诊断技术有其自身的局限性，例如 蛋白质纳米孔堵塞，需要标记步骤，经常出现假阳性/阴性结果，或较短 Basepair阅读长度。为了克服阻碍当前生物医学科学的局限性，有以下几点 迫切需要开发以严谨的基础科学为基础的新平台。家长区奖 主要由本科生研究人员参与研究串列的本征电荷转移特性 与MoS2表面相互作用的DNA重复，最终可能表现为无标记传感 未来的平台。该项目迫切需要一台导电原子力显微镜(C-AFM)进行研究 界面电荷转移特性对电化学的补充和验证 电荷转移行为。 利用理论和实验研究，PI假设DNA重复可以 由于差分产生与序列和长度相关的无标记电荷转移信号 碱基对二硫化钼(MoS2)的亲和力。这对通过严格的 父级奖励中详细说明的计划。目前，我们正在进行电化学测量， 必须通过表面探针显微镜技术进行确认，例如C-AFM。在具体目标上， PI计划研究66个两种不同长度的序列，特别是(1)研究序列- TNR/MoS_2界面的从属电荷输运，以及(2)研究与长度有关的电荷 在界面上传输。实验还包括研究序列浓度的影响 和构象。 这项补充助学金将培训本科生研究C-AFM技术，这是一种 强大的表面探头技术，用于表面化学和材料科学研究。 最终，这项补充奖将证实我们在家长奖和 提供关键信息，以开发新的敏感技术来检测 长度突变。

Project Summary Expansion of tandem DNA repeats—trinucleotide repeats or TNR—cause more than fifty genetically transferrable disorders, which affect 4 million people every year. Current state-of-the-art diagnostic technologies for genetic testing for length mutations have their own limitations such as clogging of protein nanopores, requiring labelling steps, frequent false positive/negative results, or short basepair read length. To overcome the limitations that hamper the current biomedical science, there is a critical need to develop new platforms standing on rigorous basic science. The parent AREA award involves mainly undergraduate researchers to investigate intrinsic charge transfer character of tandem DNA repeats interfaced with MoS2 surfaces that may ultimately manifest into a label-free sensing platform in future. The project urgently needs a conductive atomic force microscope (C-AFM) to study the electrical charge transfer property of the interface to complement and validate electrochemical charge transfer behavior. Leveraging on theoretical and experimental studies, the PI hypothesizes that DNA repeats can produce sequence- and length-dependent label-free charge transfer signals due to the differential affinity of the nucleobases for molybdenum disulfide (MoS2). This is critical to study through a rigorous plan as detailed in the parent award. Currently, we are performing electrochemical measurements that have to be confirmed by surface probe microscopy techniques, such as C-AFM. In the specific aims, the PI plans to study 66 sequences of two different lengths and specifically (1) investigate sequence- dependent charge transport at TNR/MoS2 interface, and (2) investigate length-dependent charge transport at the interface. The experiments also involve studying the effects of sequence concentration and conformations. This supplement grant will train the undergraduate researchers on C-AFM technique which is a powerful surface probe technique used in surface chemistry and materials science researches. Ultimately, this supplement award will substantiate our electrochemical study in the parent award and provide a critical piece of information to develop a new and sensitive technology for the detection of length mutations.