ADSORPTIVE STRIPPING VOLTAMMETRIC MEASUREMENTS OF CHROMIUM ACCUMULATION IN MICE ORGANS USING MERCURY FILM MICROELECTRODES

Chromium is the metallic species of most concern with the use of stain less steel implants. To study the distribution of chromium in mice org ans with time, several animals were subcutaneously injected with 2.70 x 10(-3) mol/L of chromium solution during a certain period of time. S quare wave voltammetry using adsorptive collection of Cr3+-DTPA comple x on a mercury film microelectrode (MFM) was used for quantitation. Op timized conditions included DTPA concentration of 2.0 x 10(-2) mol/L, sodium acetate 4.0 x 10(-2) mol/L, sodium nitrate 0.40 mol/L, potassiu m permanganate 1.0 x 10(-3) mol/L, pH ca. 6.1, deposition potential of -1.15 V, deposition time 20 s, frequency 100 Hz, step 2.5 mV and an a mplitude of 20 mV. The detection limit of the method was 1.54 x 10(-8) mol/L after deposition of 20 s. Other species presented in the biolog ical material such as calcium and iron do not interfere with the chrom ium determinations. The accuracy of the proposed method was checked by comparing the results with those obtained by atomic absorption spectr ometry (AAS) yielding good agreement. The results showed an increase o f chromium levels with time in liver, kidney and spleen, indicating th at this metal is partially accumulated in the studied organs.