Updated determination of trace amounts of zinc with dibromo-O-nitrophenylflurone by primary-secondary wavelength spectrophotometry

The reaction between zinc (Zn²⁺) and dibromo-o-nitrophenylflurone (DBNPF) was studied at pH 9. It was sensitive and selective in the presence of fluoride and triethanolamine. Due to the effect of excess DBNPF, the new method named as primary-secondary wavelength spectrophotometry (PSWS) was applied instead of ordinary spectrophotometry for the determination of trace amounts of zinc. Results showed that such a method resulted in a better precision and higher accuracy than the ordinary method. By analyzing several samples, the relative standard deviations were less than 7.8% and the recovery rate of Zn between 93.3 and 110%. This article was submitted by the authors in English.