Analytic equipment 3 Analytical strategy 3 Antioxidants 3 Chlorine compounds 3 Color 3 Colorimetric deter-mination 3 Colorimetry 3 Dietary supplements 3 Dihydroquercetin 3 Flavonoid 3 Green Paper 3 Iron compounds 3 Microfluidic paper-based analytical device 3 Microfluidics 3 Paper-based analytical devices 3 Silver compounds 3 Solid phasis 3 Solid-phase 3 Solid-phase spectrophotometry 3 antioxidants 3 colorimetry 3 dihydroquercetin 3 flavonoids 3 microfluidic paper-based analytical devices 3 optical sensors 3 solid-phase spectrophotometry