Authors: M.H. Sousa, E.S. Lins, F.A. Tourinho, J. Depeyrot, W.D. Martins, L.F. Zara, C.F.S. Castro and G.R. de Castro
Affilation: Universidade de Brasilia, Brazil
Pages: 393 - 396
Keywords: magnetic colloids, ICP-OES, slurry introduction
In the biomedical field, some applications of nanomaterials require dynamically quantifying them in blood and tissues probes. Nevertheless, the usual methods which are employed to titrate the nanoparticles require their dissolution before the chemical analysis, step which induces a loss or a sample contamination. Regarding to minimize these effects, we take advantage of the reduced grain size and the high stability of our magnetic colloids to develop a new method to determine their composition and concentration by using inductively coupled plasma optical emission spectroscopy (ICP-OES). In this way, the chemical composition of a series of sols containing size-tailored NiFe2O4 and CuFe2O4 nanograins (chemically synthesized) was analyzed by the slurry sample introduction, in which the sol is directly injected in the ICP-OES. The experimental conditions such as aerosol gas flow rate and colloidal stability were optimized for using aqueous calibration curves in the slurry nebulization technique. Then, the results of direct sampling and those of conventional dissolved particle analysis well compare, showing therefore the efficiency of the proposed method. In effect, its preparation is simple, so contamination can be lowered, no aggressive reagents are needed, it is relatively quick and calibration can be done using aqueous standards.