Use Of The Mikro-Dismembrator S In Trace Analysis And Research Of Contaminations; Trace Element Analysis Via Homogenization By "Brittle Fracture Technique - Sartorius Stedim Biotech Mikro-Dismembrator S Mode D'emploi

5.2 Use of the Mikro-Dismembrator S in Trace Analysis
and Research of Contaminations
5.2.1 Trace Element Analysis via Homogenization by
"Brittle Fracture Technique"
The use of the Mikro-Dismembrator II
element analysis and in other applications has proven to
be an optimum method to prepare samples for analysis.
Applications include grinding and homogenization of
soft tissues (after deep-freeze or freeze-drying), medium
solid and solid organic and inorganic material from
biological source (teeth, bones, hairs, nails, etc.). With
the brittle fracture technique (BFT) any kind of
biological material, even if temperature-sensitive, can be
homogenized without any problems. The BFT -
technique uses the brittleness of the material under the
temperature of liquid nitrogen (-196 deg C).
Fig. 8: Distribution profile of the some element in trace
element analysis of bovine liver (6 assays per
substance)
part A: distribution profile without
homogenizing
part B: distribution profile after
homogenizing
5-2)
Reported for the precursor of the Mikro-
Dismembrators S, the Mikro-Dismembrator II.
5-2 )
in trace
1. Fill test sample together with PTFE grinding balls into
a PTFE shaking flask. Immerse shaking flask into liquid
nitrogen for a few seconds to minutes.
2. Immediately afterwards mount shaking flask into the
holder of the homogenizer and start the device. A
running time of about 1-2 minutes may suffice for
optimum grinding (required time will be according to
the necessary fineness for the assay).
The BFT technique allows for fast homogenizing of
representative samples of bovine liver, for instance.
Assay methods without preceding homogenization,
often show large deviations of single analysis, resulting
in broad distribution (straggling) of the results.
Preceding homogenization provides highly reproducible
results with low straggling. See fig. 8 for details.
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