Bismuth Microelectrode Array for Adsorptive Stripping Voltammetry to Detect Lead and Cadmium in Beverage

A heavy metal sensor fabricated by microelectronic mechanical system (MEMS) technology was described in this study. The sensor is three-electronic system which consisted of Bi microelectronic array working electrode, Pt counter electrode and Ag/AgCl reference electrode. Bi is low-toxic heavy metal, so the using of Bi as reaction substances can make detection process more safely. Microarray electrode takes many advantages, such as high-throughput, miniaturization and anti-interference. The experiment result shows that the sensor has a good performance in simultaneously detecting Pb2+, Cd2+. The detection limits of these two metals are 0.067 mg/L (Pb) and 0.064 mg/L (Cd) respectively with good repeatability. The sensor has been applied to detect Pb2+ (0.1 mg/L) and Cd2+ (0.025 mg/L) in Orange juice with satisfactory results.