Inexpensive, Field-Portable, Rugged, Voltammetric Sensors Based on Functionalized Microporous Membranes

This work proposes further development of small, ruggedized, very lightweight, inexpensive, field-portable sensors for detection of multiple analytes in the environment. Unique modifications of voltammetric techniques allow fingerprint detection/discrimination of multiple analytes in presence of interferents. The sensors are 3-modular: Disposable sensor probe; Microcontroller; Control/display interface (Android phone or stand-alone touch-screen LCD, continuously-updatable firmware/software). In Phase I, detection, quantitation of multiple metals to < 5 ppb, munitions residues to < 7 ppb, and hydrocarbons to 1 ppb, was demonstrated in NIST soil, sediment and field water samples, with use of unique, environmentally-benign sensing electrodes fabricated for the first time. Sensing probes were reduced to 6x12x1 mm. In additional work done specifically for this proposal, detection of all analytes was demonstrated in water containing mud, humic acid, sump wastes. The Phase II work will: Demonstrate sensing of all analytes of interest simultaneously at even lower detection limits; optimize Microcontroller and data-processing software; fabricate complete field-use sensor toolkits with Android cellphone or stand-alone touch-screen LCD control/display interfaces; carry out extensive shelf-life, environmental durability tests; design small, semi-automated pilot plant. The work leverages this firms ongoing Army work in voltammetric electrochemical sensors for CW agents/TICs, with already-identified government customers and a commercial partner.