LAUSR

An analytical procedure for the multielement determination in enteral nutrition formulations employing slurry sampling and inductively coupled plasma optical emission spectrometry (ICP OES) is proposed. A two-level full-factorial design was applied to assess the influence of the presence of stabilizing agents (HNO3, Triton X-100 and ethanol) on the composition of the slurry. Multiple response was established as a dependent variable. The experimental conditions for the preparation of the slurry were: 2.0 mL of sample and 8.0 mL of 10% (v/v) HNO3. The limits of detection (LOD) were 5; 9; and 10 µg L-1 for Cu, Fe, Zn, respectively. For P, and K, the LOD were 8 and 24 mg L-1, respectively. The method was applied for the analysis of three enteral nutrition formulation samples and the obtained concentrations ranges were (in mg L-1): 0.41-0.43 (Cu), 2.0-2.9 (Fe), 1.7-3.1 (Zn), 682-1409 (K), and 217-344 (P).