title: A flow injection analysis system for monitoring silver (I) ion and iodine residuals in recycled water from recovery systems used for spaceflight.
abstract: A laboratory-built flow injection analyzer is reported for monitoring the drinking water disinfectants silver (I) ion and iodine in water produced from NASA's water recovery system. This analyzer uses spectrophotometric detection with a custom made 10cm optical flow cell. Optimization and interference studies are discussed for the silver (I) ion configuration. Subsequent results using the silver (I) configuration with minor modifications and alternative reagents gave promising results for iodine determinations as well. The estimated MDL values for Ag(+) and I2 are 52μg L(-1) Ag(+) and 2μg L(-1) I2; the mean percent recoveries were 104% and 96.2% for Ag(+) and I2 respectfully; and percent relative standard deviations were estimated at 1.4% for Ag(+) and 5.7% for I2. The agreement of this potentially multifunctional analyzer to reference methods for each respective water disinfectant is measured using Bland-Altman analysis as well as more traditional estimates.
authors.affiliation: Department of Chemistry, The University of Memphis, Memphis, TN 38152, USA.
authors.forename: Jill P
authors.initials: JP
authors.lastname: Williamson
authors.forename: Gary L
authors.initials: GL
authors.lastname: Emmert
mesh_terms: D004784:Environmental Monitoring / Q000379:methods*; D017022:Flow Injection Analysis / Q000295:instrumentation*; D007455:Iodine / Q000032:analysis*; D057230:Limit of Detection; D059027:Recycling / Q000379:methods*; D012834:Silver / Q000032:analysis*; D013026:Space Flight / Q000379:methods*; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D014874:Water Pollutants, Chemical; D014867:Water; D012834:Silver; D007455:Iodine
keywords: Disinfectant; Flow analysis; Iodine; Silver ion