Sumate PengpumkiatJintana NammoonnoyWatcharaporn WongsakoonkanPajaree KonthonbutPornpimol KongtipValaya Alongkorn Rajabhat UniversityMahidol UniversityNational Institute of Metrology (Thailand)2020-08-252020-08-252020-08-01Sensors (Switzerland). Vol.20, No.15 (2020), 1-15142482202-s2.0-85088567853https://repository.li.mahidol.ac.th/handle/20.500.14594/57691© 2020 by the authors. Licensee MDPI, Basel, Switzerland. A detection method for type-II pyrethroids in an environmental water sample using a microfluidic paper-based analytical device (µPAD) is reported here. The detection approach is based on the formation of cyanide from the hydrolysis of type-II pyrethroids and the colorimetric detection of cyanide on a layer-based µPAD. Parafilm and inexpensive laminating pouches were used to create a hydrophobic barrier for the assay on the µPAD. This detection approach was selective to type-II pyrethroids in water for which an environmental water sample was tested. The calibration curves for cypermethrin, deltamethrin, cyhalothrin, and fenvalerate ranged from 2 to 40 µg/mL without sample preconcentration. The lower concentrations of type-II pyrethroids can be assessed by including a preconcentration step prior to the detection on a µPAD. This detection system provides an alternative platform for fast, semiquantitative testing for pesticide contamination in environmental surface water by allowing for portability, low reagent/sample consumption, and low-cost testing.Mahidol UniversityBiochemistry, Genetics and Molecular BiologyChemistryEngineeringPhysics and AstronomyArticleSCOPUS10.3390/s20154107