Simultaneous determination of trace elements in serum by ICP-AES for clinical applications

For the clinical application of ICP-AES, deproteinzation of serum as pretreatment was studied for the determination of nine eliments (Mg, Ca, Fe, Cu, Zn, P, Si, Na and K) in serum by ICP-AES. A mixed solution of nitric acid and trichloroacetic acid was used as the deproteinization solution of serum. To a 0.5 ml portion of serum were added 1.5 ml of water and 4.0 ml of the deproteinization solution. The recommended final concentrations of nitric acid and trichloroacetic acid in the treated serum solution were 0.28 M and 5 %, respectively. After the treated serum solution had stood for 15 min, it was mechanically mixed and then centrifuged at 3000 rpm for 10 min. The elements in the supernatant were then determined by ICP-AES. From a comparison of the results by this method and those by a ICP-AES method conducted in conjunction with a Uniseal Teflon bottle digestion method for pretreatment of serum and those by automatic analytical methods, the present method was shown useful for the determination of elements in serum.