The CUPRAC-paper microzone plates as a simple and rapid method for total antioxidant capacity determination of plant extract

The current work was aimed to develop the paper microzone plates (P mu ZP) as a scanometric system for determining the total antioxidant capacity of plant extracts. The P mu ZP was constructed by immobilizing CUPRAC reagent onto 70-well of patterned paper as a sensing zone for the scanometric detection system. The light blue-sensing zone showed a sensitive response to standard antioxidant (rutin) by forming light yellow color adducts which can be scanned and quantitatively measured by image processing program as a scanometric method. The sensor gave a notable signal at 8 min after rutin addition and presented a linear response in the concentration span of 1-10 mM. The developed method was shown to be reproducible (RSD < 3%) and accurate (98-101% recovery) for determining the TAC of plant extracts (as mM rutin equivalents) and showed strong correlation (r = 0.9887) with the standard CUPRAC method, suggesting that it can be applied for the simple and rapid method for TAC determination.