Determination of Gallic Acid in Tea by a Graphene Modified Glassy Carbon Electrode

Abstract

The determination of gallic acid (GA) content by a graphene modified glassy carbon electrode (graphene/GCE) was studied. The electrochemical behavior of GA on this electrode was studied by cyclic voltammetry (CV), and the standard curve was constructed by differential pulse voltammetry (DPV). The results indicate that graphene has a good catalytic effect on GA in phosphate buffer (PBS) and shows a linear response toward GA in the 8.0×10-8 to 2.0×10-5 mol•L −1 concentration range. The detection limit is 1.2×10-9 mol•L −1. This proposed determination for GA on graphene/GCE was carried out in the presence of potentially interfering compounds such as sorbic acid, tartaric acid, ascorbic acid and glucose. The content of GA in green tea was determined by this method, and the recovery was 97.9%-100.6% with satisfactory results.

A Concise Profile of Gallic Acid—From Its Natural Sources through Biological Properties and Chemical Methods of Determination

“…These include voltammetric, amperometric, and polarographic techniques (see Table 3 ). Electrochemical techniques pay more attention to the electrochemical oxidation of hydroxyl groups in gallic acid [ 119 ]. The advantage of these methods over the other methods that are characterized by expensive equipment, complicated operation, time consumption, sample preparation and a large amount of toxic organic solvents is huge [ 120 , 122 ].…”

Determination of 3,4,5-Trihydroxybenzoic Acid Exploiting a Visible-Light-Driven Photoelectrochemical Platform: Application in Wine and Tea Samples

“…The linear response of the sensor was compared to other works reported in the literature for the detection of THBA (Table 1). 7,[12][13][14][15][16]18,20,22,[58][59][60][61][62] It is observed that, concerning the techniques presented in Table 1, the proposed method showed satisfactory results, since it can be used successfully in the determination of THBA. It is also important to emphasize that the proposed method does not involve co-precipitation steps, flow injection, and it does not require large amounts of samples, being easy to prepare and operate.…”