Milestone Srl MA213-003 – DMA-80 EVO – User Manual
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8.6.4 How to work with liquid samples in auto-sampler mode, in order to avoid
evaporation.
With liquid samples, metal boats can be used only in single mode, to minimize the loss of mercury due to
chemical interaction between the acid matrix and the metal boat.
Milestone offers boats made of quartz, a completely inert material, to solve this problem and ensure good
results.
The following two experiments illustrate the problem, and the effectiveness of this solution.
TEST 1:
Metal boat effect with lost of mercury
6 samples of 105 µg/Kg (10ng) have been prepared and run by auto-sampler mode.
After starting the autosampler, the waiting metal sample boats react chemically with the liquid standard,
and consequently there is a loss of mercury.
TEST 2:
Quartz boats (without lost of mercury).
5 samples of 105 µg/Kg (10ng) have been prepared and run in auto-sampler mode.
All the runs have been successfully done without evaporation, good stability and reproducibility, RSD: 0.85
We recommend using the quartz boats for all liquid samples.
With the quartz boats, is possible to optimize the recovery (<1 ng absolute) of Hg without a pre-
concentration step.
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