Improved sensitivity for transition metal ions by use of sulfide in the Belousov-Zhabotinskii oscillating reaction

A highly sensitive method for the determination of trace amounts of transition metal ions by use of sulfide in the Belousov-Zhabotinskii (B-Z) oscillating chemical reaction is proposed. The use of sulfide increased strongly the sensitivity of the B-Z reaction for transition metal ions, such as Ag+, Pb2+, Hg2+, Cd2+, Cu2+,and Bi3+. Results showed that the variational ratio of oscillating period (PR) is linearly proportional to the negative logarithm of concentration of metal ions. The detection limit is down to 10−12 mol L−1. Various influencing factors on the determination were also examined.