Colorimetric-Solid Phase Extraction (C-SPE)
Ensuring that spacecraft water is potable is of critical importance to the success of the space program. Through a multidisciplinary collaboration, we are developing a strategy to simply and rapidly monitor levels of biocides (e.g., Ag (I) or I2) in the drinking water storage and distribution systems on the international space station and shuttle. The core of this platform is C-SPE with spectrophotometric readout, where a membrane is impregnated with biocide specific reagents that undergo a color change as a function of analyte concentration. A light weight, commercially available, hand-held diffuse reflectance spectrometer is then used to analyze a developed membrane. This approach has been successfully applied in both laboratory and microgravity environments with analogous results, where detection limits for the system are well within NASA's stipulated range.