Copper phthalocyanine conjugated graphitic carbon nitride nanosheets as an efficient electrocatalyst for simultaneous detection of natural antioxidants

Foodborne antioxidants including ascorbic acid (AA), caffeic acid (CA) and gallic acid (GA) are beneficial nutritional sources and thereby the analysis of the critical antioxidant is demanding for public health. Here, a sonochemical method was used to obtain hybrid copper-phthalocyanine conjugated graphitic carbon nitrides nanosheets (CuPTc/g-C 3 N 4 Ns) in which carboxylic acids and hydroxyl groups were added on the basal plane of g-C 3 N 4 . As prepared materials were characterized by various physicochemical and electroanalytical techniques, the CuPTc/g-C 3 N 4 Ns nanocomposite showed an excellent electrocatalytic activity towards antioxidants quantifications by using Indium Tin Oxide (ITO) coated glass plate. Under optimized experimental conditions, sensitive electrochemical detection of antioxidants was achieved on the CuPTc/g-C 3 N 4 Ns nanocomposite-modified ITO which resulted in wide linear concentration range of 0.05-500 µM (AA), 0.05-501 nM (CA) and 10-445 nM (GA) and the limit of detection (LOD) of 0.006 µM, 0.008 nM and 0.5 nM respectively. Furthermore, the fabricated sensor was successfully used for the antioxidants determinations in different commercial fruit juice, alcoholic beverages and tea samples with good recovery results demonstrating a hybrid phthalocyanine conjugated 2D carbon nanocomposite as an efficient electrocatalyst of desirable practical importance.