SBIR Phase I: Real-time, In-situ Detection of Escherichia Coli Bacteria in Water Using Graphene

这个小企业创新研究（SBIR）一期项目旨在开发一种基于石墨烯-金纳米粒子的传感平台，用于检测水中的大肠杆菌（E. Coli）细菌。水中大肠杆菌的实时在线检测是一个尚未满足的需求，但对水质监测至关重要，以确保公共安全。已有几种方法用于水中大肠杆菌的检测；然而，这些方法存在灵敏度低、耗时长、成本高等缺点。因此，迫切需要一种灵敏、快速、经济的检测技术，以解决传统大肠杆菌检测方法的局限性。SBIR一期项目的智力优势是通过对大肠杆菌检测的优越传感性能和将石墨烯用作场效应晶体管传感器中的传感元件来满足未满足的需求。本项目的具体研究目标是：(1)提高传感器的灵敏度；(2)在流动水中测试传感器性能；(3)研究传感器的稳定性/可靠性；(4)考察传感器的回收潜力。该项目有望开发出一种可靠、低成本的大肠杆菌传感器，检测限低于1 cfu/mL。开发一种新的大肠杆菌检测平台，以改善淡水供应的公共安全，从而实现该项目的更广泛影响/商业潜力。实时、原位传感器也将有助于智能配水网。拟议的活动将提高生物传感性能（检测极限、稳定性和回收），并最大限度地提高实时传感平台的商业化机会。目标商业产品将是一种手持式、独立的装置，可用于测量井水、水龙头和冰箱中的大肠杆菌浓度。该平台使用的主要传感材料，即热还原氧化石墨烯和金纳米颗粒，价格实惠，特别是考虑到每个传感器所需的材料很少。该项目有望对抗菌抗体与细菌之间的结合相互作用产生更深入的了解，这将有助于开发下一代传感器，以灵敏和准确地检测食源性和水源性病原体。该项目还将培养威斯康星大学密尔沃基分校纳米材料和纳米器件领域的博士后和研究生。

This Small Business Innovation Research (SBIR) Phase I project aims to develop a graphene-gold nanoparticle-based sensing platform for detection of Escherichia Coli (E. Coli) bacteria in water. Real-time, inline detection of E. coli in water is an unmet need but critical for water quality monitoring to ensure public safety. Several methods have been used for E. coli detection in water; however, these methods have disadvantages such as low sensitivity, time-consuming, and high cost. Therefore, there is a great demand for sensitive, fast, and cost-effective detection technology that could address the limitations of conventional methods for E. coli detection. The intellectual merit of the SBIR Phase I project is realized by the superior sensing performance for the detection of E. coli and the application of graphene as the sensing element in a field-effect transistor sensor to fulfill unmet needs. Specific research objectives of the project are: (1) to improve the sensor sensitivity; (2) to test the sensor performance in flowing water; (3) to study the stability/reliability of the sensor; (4) to examine recycling potential of the sensor. The project is expected to lead to a reliable and low-cost E. coli sensor with a lower detection limit of 1 cfu/mL or below. The broader impact/commercial potential of this project will be realized by developing a new E. coli detection platform for improving public safety in the fresh water supply. The real-time, in-situ sensor will also contribute to a smart water distribution grid. The proposed activities will improve the biosensing performance (detection limit, stability, and recycling) and maximize the commercialization opportunities of the real-time sensing platform. The targeted commercial product will be a handheld, stand-alone unit that can be used to measure the E. coli concentration in well water, water from our faucets and refrigerators. The major sensing materials used in this platform, i.e., thermally-reduced graphene oxide and gold nanoparticles, are affordable, particularly given the small amount of materials needed for each sensor. The project is expected to generate a deeper understanding of the binding interaction between anti-bacterial antibody and bacteria, which will be useful for developing next-generation sensors for sensitive and accurate detection of food-borne and water-borne pathogens. The project will also train University of Wisconsin-Milwaukee postdocs and graduate students in the areas of nanomaterials and nanodevices.