Materials and methods
Materials
Preparation of cadmium
The analytical grade salt Cd(NO3)2 was used to prepare stock
solution (1000 mg L1) of Cd2+. The desired concentrations
were prepared by dilution of the stock solution with deionised
water. The initial pH was adjusted with concentrated HCl or
NaOH. The initial metal concentration (10 mg L1) was measured
using a flame atomic absorption spectroscopy (Perkin
Elmer AAnalyst 100). Samples were diluted before the
required analysis to set the calibration linear range