Determination of aluminium in infusion solutions by inductively coupled plasma atomic emission spectrometry—a critical comparison of different emission lines

Abstract

Seven emission lines for the determination of Al in infusion solutions by means of inductively coupled plasma atomic emission spectrometry were compared. For this comparison, wavelength scans of different samples were made in order to study the background in the region of each line and to inspect for interference structures arising from molecular bands of water and argon. Background equivalent concentrations and detection limits were calculated for the emission lines at 167, 237, 394 and 396 nm. The detection limits were 1.2 µg l^–1 for the 167 nm line, 8.8 µg l^–1 for the 237 nm line, 10 µg l^–1 for the 394 nm line, 4.7 µg l^–1 for the 396 nm line and > 10 µg l^–1 for the other three lines (226, 308 and 309 nm). The Al content of various infusion solutions was determined on different days using the three emission lines with the lowest detection limits (167, 237 and 396 nm). Day-to-day-variation was approximately 5% in all cases. As a final step, the Al contamination of 25 infusion solutions for parenteral nutrition was evaluated by using the two most suitable emission lines (167 and 396 nm). No statistically significant differences between the results were detected. Advantages and disadvantages of these two emission lines for the determination of Al are discussed.