SBIR Phase II: Universal electronic platform and system for rapid (direct from sample) phenotypic Antibiotic Susceptibility Testing (AST)

SBIR第一阶段项目解决了减少目前用于确定治疗感染的靶向抗生素（和剂量）的测试相关时间的需要。败血症和感染性休克是美国医院死亡的主要原因之一，每年造成25万人死亡（估计占所有医院死亡人数的30-50%）。要与这些高死亡率作斗争，时间至关重要。在感染性休克的最初5 - 6小时内进行靶向（相对于广谱）抗生素治疗可使存活的可能性提高大约50%。本项目结合电子学和微通道流体学，快速获得抗生素敏感性的结果。该项目需要工程、软件开发和方法开发，从而产生利用一次性卡片进行测试的仪器。由此产生的产品将允许更快地从广谱过渡到靶向抗生素治疗（1天-周），带来主要好处：(1)通过更快地过渡到定向抗生素治疗，患者的预后大大改善；(2)减少住院时间（减少重症监护时间），为医疗保健系统节省大量资金（估计每年至少节省37.5亿美元的成本）。(3)减少广谱抗生素治疗减少了目前全球卫生保健环境中抗生素耐药性的培养。该项目使用微通道电阻抗谱（m-EIS）来测量悬架的“体电容”（Cb）。Cb是对悬浮液中活细胞膜上瞬时积累的电荷量的量度。细胞增殖导致Cb增加，而细胞死亡导致Cb减少。使用m-EIS在存在候选抗生素和剂量的情况下测量细菌，是稳健、敏感和极快的，可以实时确定细胞生长、停滞或死亡（大约4小时）。该项目将开发一种快速，直接从样品，廉价的商业系统。这是通过使用商业MNPs从临床样品（如血液培养液、尿液、痰液等）中分离微生物，并将病原体重新悬浮在指定体积的生长培养基中，以获得含有最佳细菌浓度的悬浮液来实现的。然后使用m-EIS在微流控卡中监测病原体的生长或死亡，在微流控卡中，病原体暴露于一系列抗生素浓度。结果是一种表型抗生素敏感性（AST）谱，在样品收集4小时内产生多种候选抗生素的最小抑制浓度（MIC）。AST和MIC信息随后用于靶向治疗感染。第一批使用该系统/方法的产品将集中在尿液和阳性血液培养肉汤样本上。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。

This SBIR Phase I project addresses the need to reduce the time associated with conducting tests currently used to establish targeted antibiotic (and dose) to treat infections. Sepsis and septic shock are one of the leading contributors to death in US Hospitals, responsible for 250,000 deaths annually (estimated at 30-50% of all hospital deaths). To combat these high death rates, time is of the essence. The administration of targeted (versus broad-spectrum) antibiotic therapy in the first five to six hours of septic shock increases the likelihood of survival by roughly fifty percent. This project combines electronics and microchannel fluidics to rapidly obtain results on antibiotic susceptibility. The project requires engineering, software development, and method development, resulting in an instrument that utilizes disposable cards to conduct the testing. The resulting product will allow transition from broad spectrum to targeted antibiotic therapy faster (1 day - weeks), leading to major benefits: (1) patient outcomes are greatly improved by faster transition to directed antibiotic therapy; (2) Reduced hospitalization stays (reduced intensive care stays), resulting in significant monetary saving for healthcare systems (estimated at a cost savings of at least $3.75B annually). (3) Reduced broad-spectrum antibiotic therapy reduces the current fostering of antibiotic resistance in healthcare settings globally. This project uses Microchannel Electrical Impedance Spectroscopy (m-EIS) to measure the "bulk capacitance" (Cb) of a suspension. Cb is a measure of the amount of charge transiently accumulated at the membranes of living cells in a suspension. Cell proliferation results in an increase in Cb, whereas cell death results in a decrease. Using m-EIS to measure bacteria in the presence of candidate antibiotics and doses, is robust, sensitive, and extremely fast, determining, in real time, cell growth, stasis, or death (in approximately 4 hrs). This project will develop a rapid, direct-from-sample, inexpensive commercial system. This is achieved by using commercial MNPs to isolate microorganisms from clinical samples such as blood culture broth, urine, sputum etc., and re-suspending the pathogens in specified volumes of growth media to obtain a suspension containing optimized concentrations of bacteria. Pathogen growth or death is then monitored using m-EIS in microfluidic cards where they are exposed to a range of antibiotic concentrations. The result is a phenotypic antibiotic susceptibility (AST) profile, yielding the minimal inhibitory concentration (MIC) of multiple candidate antibiotics within 4 hours of sample collection. The AST and MIC information is then used to treat infections with targeted therapeutic. The first products utilizing this system/method will focus on urine and positive blood culture broth samples.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.