Oxalic acid (OA) widely exists in plants, animals and microbes in the nature, and it can beabsorbed into the human body by food. Stone disease may be triggered if high content of oxalicacid maintain long-term in our body. Stone disease can be prevented by food or urinary oxalatedetection. So it is necessary to develop a simple, low cost, rapid and sensitive analytical methodfor the detection of oxalic acid. Biomolecule ascorbic acid (AA) and dehydroascorbic acid areknown as a vitamin C, which is widely foun...