Determination of chromium in cerebrospinal fluid using electrothermal atomisation atomic absorption spectrometry

A rapid method to determine the chromium content of cerebrospinal fluid (CSF) samples using electrothermal atomization atomic absorption spectrometry (ETA-AAS) with deuterium-arc background correction is described. The chromium concentration in CSF was evaluated by the standard addition method. Sample dilution (1 + 1) with 0.25% (m/v) Triton X-100 and 4.5% (v/v) HNO3 gave the best combination of sensitivity, reproducibility, and low blank reading compared with dilution using other solvents. Within-batch reproducibility was 3.2% for 20 CSF samples, between-batch reproducibility was 4.7%. CSF samples from 43 healthy volunteers collected in a manner designed to avoid contamination yielded chromium concentrations of 14.6 ± 6.3 ng mL−1.