Monitoring of heavy metal cadmium in environmental water sample by eggshell membrane preconcentration coupled with GF-AAS

In order to evaluate the effects of heavy metals discharged in the environment water, a novel method using a glass column packed with eggshell membrane (ESM) as a new adsorption material was developed for the preconcentration of trace Cd in environmental water sample prior to its monitoring by graphite furnace-atomic absorption spectrometry (GF-AAS). The adsorption behaviors of the analyte on ESM under dynamic conditions were studied systematically. It was found the ESM is an effective solid phase extractant for the adsorption of trace cadmium at pH range of 5.5-7.5. Under the optimized conditions, the detection limits of this method for Cd was 0.13 ng mL^-1, and the relative standard deviation (R.S.D %) was 3.1% (n =11, c = 2 ng mL^-1. The proposed method has been successfully applied to monitoring of trace cadmium in environmental water samples with satisfactory results.