Total cation concentration of the two drug samples were determined both by the Inductively Coupled Plasma Mass Spectrometer (ICPMS- Perkin Elmer Sciex ELAN- 6000) and Perkin Elmer-2800 Atomic Absorption Spectrophotometer (AAS) after acid digestion [28 (link)] of the inorganic portion of the drugs. The water soluble portion of each drug sample was obtained by filtering each aqueous suspension which was kept in a horizontal shaker at room temperature for 5 h and then allowing equilibrating for 19 h. Analyses of the solutions were carried out on the AAS.
The instruments were calibrated using analytical grade standard solutions of each element. The accuracy of the analytical procedure was evaluated by analyzing reagent blanks routinely with samples as well as by triplication of sub-samples. Detection limits of different elements vary from 1 to 0.001 mg/L for both ICP-MS and AAS. Analyses were done at the Activation Laboratories Ltd. Ontario, Canada and Department of Geology, University of Peradeniya, Sri Lanka, respectively.
The instruments were calibrated using analytical grade standard solutions of each element. The accuracy of the analytical procedure was evaluated by analyzing reagent blanks routinely with samples as well as by triplication of sub-samples. Detection limits of different elements vary from 1 to 0.001 mg/L for both ICP-MS and AAS. Analyses were done at the Activation Laboratories Ltd. Ontario, Canada and Department of Geology, University of Peradeniya, Sri Lanka, respectively.