Abstract:
This study presents an octopole collision cell ICP-Q-MS methodology for interferencefree
multi-element analysis of urine. The attention was paid to the performance of
the 4th generation octopole-based collision cell in the Agilent 7900 Series ICP-MS in
He-mode with kinetic energy discrimination (KED) for the elimination of polyatomic
ions that are the main source of spectral interferences during the analysis of numerous
elements, such as V, Cr, Fe, Co, Ni, Cu, As, Se, etc. However, collision mode using
helium gas had the additional benefit of reducing the response for major matrix
elements, thereby effectively raising the upper linear calibration range for these
elements. Afterwards, the major elements could be determined in the same analytical
run as the trace elements in the range of analytes typically reported in urine samples.
The analysis was carried out after the initial 10-fold dilution of the urine samples and
Rh was used as an internal standard to diminish non-spectral interferences originating
from the sample matrix. Due to the excellent detection capability and practically no
interferences, the method could be finally employed for analysis of 26 elements.
Accuracy of the method was checked by the regular use of certified reference materials
SeronormTM Trace Elements Urine Blank Lot OK4636 and SeronormTM Trace
Elements Urine L-1 Lot 1011644, as well as by accurate isotope ratios measurements
if possible.
