環境水中のアンモニア性窒素を高感度かつ迅速に検出するための新規3D-CB/HEC-CH@Cuハイブリッド電極

In this paper, a electrode based on 3D-printed carbon black (3D-CB), and coated with a hydroxyethylcellulose/chitosan (HEC/CH) bilayer and finished by copper electrodeposition, is presented for the electrochemical sensing of ammonia nitrogen (AN) in water. Measurements were performed using square-wave voltammetry (SWV) in borate buffer (pH 9) under optimized conditions. The electrochemical method displayed good linear relationship between 0.7 and 20.4 mg L^-1 of AN with limits of detection (LOD) and quantitation (LOQ) of 0.014 and 0.043 mg L^-1 respectively, good precision (RSD ≤≃4.18% intra/inter-day, n = 10), and practical throughput (∼70 analyses per h). Accuracy in real waters was evaluated through standard-addition and spike-recovery experiments, yielding ∼99.8% recoveries. Statistical analysis was used to compare the obtained results to the expected values and no significant difference was observed between added and found concentrations. Therefore, the proposed 3D-CB/HEC-CH@Cu SWV method presents a viable alternative for the efficient, low-cost and safe determination of ammoniacal nitrogen in the water quality control process.