There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
Microwave assisted pre-treatments for atomic spectrometric determination (inductive
coupled plasma-optical emission spectrometry, ICP-OES or flame atomic absorption spectrometry,
FAAS) of metallic elements, usually present in antidandruff shampoos, are proposed.
They are based on the digestion of the sample with HNO(3) into a closed reactor, which
is irradiated at 800 W for a few minutes. Selenium was determined by ICP-OES. The
limit of detection was 0.11 mg l(-1); the relative standard deviation (R.S.D.) for
the selenium content in the samples was in the 0.6-3.6% range. The results obtained
were in agreement with the label contents and the recovery of the proposed method
was in the 100-106% range. Zinc and cadmium were determined by FAAS. The limit of
detection for zinc determination was 0.078 mg l(-1); the R.S.D. for zinc contents
was in the 0.8-8.6% range. A limit of detection of 0.09 mg l(-1) was obtained for
cadmium determination; the R.S.D. for cadmium contents was in the 0.7-2.7% range.
The determinations were performed after two different sample mineralization pre-treatments
- dry ashing (in an electric furnace) and wet mineralization (in a microwave oven).
Both methodologies provided comparable results for zinc and cadmium determination
in shampoos. The proposed microwave assisted digestion procedures allow a precise
and accurate determination of selenium, zinc and cadmium in commercial antidandruff
shampoos, and the sample pre-treatment is less time-consuming than the classic methods.