Die Embryonalentwicklung der Paradiesschnecke ... - TOBIAS-lib

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et al. (2001, 2003) or with electrothermal atomic spectrometry (ET-AAS) after
microwave-assisted digestion according to Sures et al. (1995). PtCl 2 concentrations
above 100 µg/L were analyzed by ET-AAS, while lower concentrations
were analyzed by ACSV. For controls and M. cornuarietis exposed
to 100 µg/L PtCl 2 the replicate number n was 8, for M. cornuarietis exposed
to 200 µg/L PtCl2 n=9, for M. cornuarietis exposed to 200 µg/L PtCl 2 plus
equimolar Ca n=5. Depending on the estimated Pt concentrations in the
exposure medium for M. cornuarietis, concentrations of Pt were measured
with inductive coupled plasma mass spectrometry (ICP-MS, Perkin Elmer
model Elan 5000, PerkinElmer Inc., Wellesley, MA, USA) or with ET-AAS
(Perkin Elmer model 4100ZL). PtCl 2 concentrations above 100 µg/L were analyzed
by ET-AAS, while lower concentrations were analyzed with ICP-MS.
Each sample was analyzed in triplicate. Detailed descriptions of analytical
procedures for ACSV and ICP-MS have been published by Osterauer et al.
(2009).
Electrothermal atomic absorption spectrometry (ET-AAS)
Tissue samples of about 20 mg fresh weight each were digested by adding 1.8
mL HNO 3 (65 vol.%, subboiled) into 100 mL perfluoralkoxy vessels. Using a
microwave digestion oven (CEM Model MDS-2000, 650 ± 50 W; Spectralab
Scientific Inc., Toronto, ON, Canada) samples were digested according to
the description of Sures et al. (1995). The resulting solution was filled
up to 2 mL with bidistilled water. Analytical measurements were conducted
with an atomic absorption spectrophotometer (Perkin Elmer Model 4100ZL).
Therefore, 20 µL of each sample, priorily diluted with bidistilled water, were
injected into a pyrolytic graphite furnace tube with L’vov platform by an autosampler
AS 70. Operation parameters and further procedural descriptions
have been published by Zimmermann et al. (2003). The detection limit for
Pt in the tissue samples was defined to be threefold the standard deviation
of the measurements of procedural blanks. For the average sample weight of
25 mg for M. cornuarietis it was found to be 62 ng/g.
For Pt analysis in the exposure medium 0.5 mL of the medium were topped
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