Synthesis of Zinc Tetraaminophthalocyanine Functionalized Graphene Nanosheets as an Enhanced Material for Sensitive Electrochemical Determination of Uric Acid

A new electrochemical sensor material has been fabricated via the non-covalent functionalization of reduced graphene oxide (rGO) and soluble tetramino zincphthalocyanines (ZnPc-NH2). Immobilization of uricase onto the synthesized nanohybrids can evidently improve the electrocatalytic activity and selectivity. The obtained composite membrane possesses a great enhancement of electron transfer rate and excellent synergistic electrocatalytic effect toward uric acid (UA) oxidation under the working potential at 0.620 V vs. Ag/AgCl with a scan rate of 0.125 V/s. The effects of the experimental parameters on the electrochemical oxidation responses of UA were investigated and optimized in detail. Under the optimized conditions, the peak currents were proportional to the UA concentration in a range from 0.5 to 100 mu mol/L with detection limit of 0.15 mu mol/L. Moreover, the developed sensor was applied for UA determination in human urine samples with high accuracy and satisfactory recovery, which is envisioned to have promising applications in monitoring UA in clinical research.