Maliwan AmatatongchaiOliver HofmannDuangjai NacaprichaOrawon ChailapakulAndrew J. DeMelloMahidol UniversityUbon Rajathanee UniversityBioIncubator UnitChulalongkorn UniversityImperial College London2018-08-242018-08-242007-01-01Analytical and Bioanalytical Chemistry. Vol.387, No.1 (2007), 277-28516182650161826422-s2.0-33845665436https://repository.li.mahidol.ac.th/handle/123456789/24288A microfluidic system incorporating chemiluminescence detection is reported as a new tool for measuring antioxidant capacity. The detection is based on a peroxyoxalate chemiluminescence (PO-CL) assay with 9,10-bis-(phenylethynyl) anthracene (BPEA) as the fluorescent probe and hydrogen peroxide as the oxidant. Antioxidant plugs injected into the hydrogen peroxide stream result in inhibition of the CL emission which can be quantified and correlated with antioxidant capacity. The PO-CL assay is performed in 800-μm-wide and 800-μm-deep microchannels on a poly(dimethylsiloxane) (PDMS) microchip. Controlled injection of the antioxidant plugs is performed through an injection valve. Of the plant-food based antioxidants tested, β-carotene was found to be the most efficient hydrogen peroxide scavenger (SAHPof 3.27∈×∈10-3μmol-1L), followed by α-tocopherol (SAHPof 2.36∈×∈10-3μmol-1L) and quercetin (SAHPof 0. 31∈×∈10-3μmol-1L). Although the method is inherently simple and rapid, excellent analytical performance is afforded in terms of sensitivity, dynamic range, and precision, with RSD values typically below 1.5%. We expect our microfluidic devices to be used for in-the-field antioxidant capacity screening of plant-sourced food and pharmaceutical supplements.Mahidol UniversityBiochemistry, Genetics and Molecular BiologyChemistryArticleSCOPUS10.1007/s00216-006-0930-3