Prawpan InpotaKamil StrzelakRobert KonckiWisaroot SripumkhaiWutthinan JeamsaksiriNuanlaor RatanawimarnwongPrapin WilairatNathawut ChoengchanRattikan ChantiwasDuangjai NacaprichaKing Mongkut's Institute of Technology LadkrabangUniwersytet WarszawskiMahidol UniversitySrinakharinwirot UniversityFlow Innovation-Research for Science and Technology Laboratories (FIRST Labs.Thai Microelectronics Center (TMEC)2019-08-232019-08-232018-01-01Analytical Sciences. Vol.34, No.2 (2018), 161-16713482246091063402-s2.0-85041863263https://repository.li.mahidol.ac.th/handle/20.500.14594/45528© The Japan Society for Analytical Chemistry. A microfluidic method with front-face fluorometric detection was developed for the determination of total inorganic iodine in drinking water. A polydimethylsiloxane (PDMS) microfluidic device was employed in conjunction with the Sandell-Kolthoff reaction, in which iodide catalyzed the redox reaction between Ce(IV) and As(III). Direct alignment of an optical fiber attached to a spectrofluorometer was used as a convenient detector for remote front-face fluorometric detection. Trace inorganic iodine (IO 3- and I - ) present naturally in drinking water was measured by on-line conversion of iodate to iodide for determination of total inorganic iodine. On-line conversion efficiency of iodate to iodide using the microfluidic device was investigated. Excellent conversion efficiency of 93 - 103% (%RSD = 1.6 - 11%) was obtained. Inorganic iodine concentrations in drinking water samples were measured, and the results obtained were in good agreement with those obtained by an ICP-MS method. Spiked sample recoveries were in the range of 86%(±5) - 128%(±8) (n = 12). Interference of various anions and cations were investigated with tolerance limit concentrations ranging from 10-6 to 2.5 M depending on the type of ions. The developed method is simple and convenient, and it is a green method for iodine analysis, as it greatly reduces the amount of toxic reagent consumed with reagent volumes in the microfluidic scale.Mahidol UniversityChemistryArticleSCOPUS10.2116/analsci.34.161