E.coREADi: Automated Microbial Assays for Drinking Water Analysis

Ensuring the safety of drinking water is a global concern and a critical need for the United States Armed Forces. The ability to rapidly detect viable indicator organisms in water sources, including total coliforms and E. coli, in near-real time has been identified as critical to mission success by the US military. The Environmental Protection Agency (EPA) approved test method currently used to measure total coliforms and E. coli is Colilert®, and requires some technical expertise, laboratory equipment, and a minimum time to results of 18 hours. Colilert also has some logistical complexities for use, including the need for technician hands-on requirements at the start and end of the assay, and stringent time requirements for collecting and analyzing samples. Thus, there is a significant need for drinking water analysis technologies that reduce the minimum time-to-result, improve operational characteristics, are designed for field use in support of forward operating bases, and provide for use in rural and resource poor areas. In response to this need, Luna Innovations has been performing extensive research and development to create a novel, rapid, specific assay for detection of E. coli and coliforms in water samples. Known as “E.coREADi™,” the assay enables presence/absence or semi-quantitative analysis of viable bacteria in 10 hours which is 8-14 hours faster than current EPA standard methods. The E.coREADi technology is being adapted for automation. Luna and partners have worked to transition the assay to low-cost microfluidic cartridges and to develop a portable instrument to automate the measurement. The system is being designed towards simple operation where 100 mL of water is added to a cartridge, the cartridge is inserted into the automated system, and a result is electronically available in 10 hours. Successful demonstrations of the integrated system thus far include recovery of chlorine-stressed bacteria, manufacturing of the microfluidic cartridges, and a fully assembled and operational prototype E.coREADi instrument. In order to be used in military or commercial applications, it is mandatory that the E.coREADi technology is EPA approved as an Alternative Test Procedure (ATP) for drinking water. This proposed DHA-funded Sequential Phase II program builds upon previous development efforts and is designed to complete validation testing of the automated system, execute an approved EPA Study Plan, initiate end-user demonstrations, and transition the technology to market.