Abstract:

A rapid method to determine trace amounts of strontium in kelp was proposed using flame atomic absorption
spectrometry (FAAS) after sample injection by on-line binary capillary. The impact of acidity and interfering ions on
detection of strontium was explored using binary capillaries of the same diameter. Samples were digested with acids, and the
interfering ions were effectively suppressed by on-line addition of sodium dodecyl sulfate (SDS). The analysis was carried
out at a flow rate of 10.0 and 1.2 L/min for air and acetylene, respectively. Results showed that the content of strontium in
kelp was 700 μg/g, as determined by the FAAS method. The limit of detection (LOD) of the method was 0.1 μg/g, the spiked
recoveries of strontium in real samples were between 97.8% and 107.4%, and the precision expressed as relative standard
deviation (RSD) was less than 5%. This method is accurate, rapid, low-cost and suitable for determination of trace strontium
in samples with satisfactory results.

Key words: on-line binary capillary, flame atomic absorption spectrometry, kelp, strontium