SBIR Phase I: Handheld graphene-based sensors for rapid detection of Salmonella species in food processing facilities

这项小企业创新研究（SBIR）第一阶段项目的广泛影响是在食品加工厂更快、更准确地检测沙门氏菌。沙门氏菌是食源性疾病最常见的致病原因。加工设施中的食品污染可能导致严重的公共卫生问题，以及代价高昂的数百万单位食品召回。目前缺乏对食品加工厂沙门氏菌进行明确检测的快速和准确的传感技术，这延误了适当控制措施的启动，并增加了向消费者传播污染和食源性疾病的可能性。该技术将在整个制造过程中以更低的成本进行更频繁的测试。完全可以期待这项技术可以应用于其他病原体的检测。拟议中的项目将创建并测试一个快速（20分钟）、手持、灵敏（每毫升1个细菌细胞）的平台，使食品加工设施能够在现场检测沙门氏菌。这项技术的创新之处在于能够避免细菌富集（22至48小时允许细菌生长），同时仍然敏感和选择性地检测沙门氏菌。该设备使用一个测试盒将细菌直接带到检测表面，检测表面由打印或刻写在测试条上的石墨烯组成，随后用沙门氏菌特异性抗体进行功能化。独特的激光处理在石墨烯中诱导出纳米级的3d结构表面，该表面对生物传感和抗体附着具有高导电性，这是实现低检测限和提高测试灵敏度的理想特性。这些技术可以组合成一个便携式平台，制作一个用户友好的手持生物传感器，并显示细菌的定量计数。集成平台（测试条和墨盒）将被设计成与现有的便携式电子阅读器接口，就像糖尿病患者在家里用血液测试条连接到带有数字显示的便携式阅读器来监测血糖水平一样。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The broader impact of this Small Business Innovation Research (SBIR) Phase I project is faster and accurate detection of Salmonella species in food processing plants. Salmonella bacteria are the most frequently reported cause of foodborne illness. Food contamination in processing facilities can lead to serious public health problems as well as costly recalls of millions of food units. Rapid and accurate sensing technology is currently lacking for definitive detection of Salmonella in food-processing plants, which delays initiation of appropriate control measures and increases the likelihood of spreading contamination and foodborne illnesses to consumers. This technology will enable more frequent testing throughout the entire manufacturing process at reduced costs. It is fully expected that this technology could be applied to the detection of other pathogens.The proposed project will create and test a rapid (20 minutes), hand-held, sensitive (1 bacteria cell per milliliter) platform to enable food-processing facilities to detect Salmonella on site. The innovation of this technology lies in the ability to avoid bacterial enrichment (22 to 48 hours to allow bacteria to grow), while still sensitively and selectively detecting Salmonella species. The device uses a testing cartridge to bring bacteria directly to a detection surface, which consists of graphene printed or scribed on a test-strip and subsequently functionalized with Salmonella-specific antibodies. Unique laser processing induces a 3D-structured surface at the nanoscale level in graphene that becomes highly conductive for biosensing and for antibody attachment, which are desirable properties for enabling low detection limits and increasing test sensitivity. These technologies can be combined into a portable platform to make a user-friendly handheld biosensor and displaying quantitative counts of bacteria. The integrated platform (test strip and cartridge) will be designed to interface with existing portable electrical readers in much the same fashion that diabetics monitor blood glucose levels at home with a blood test strip that connects to a portable reader with a digital display.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.