Lovibond Tintometer MD 100 Manuel D'instructions page 5

Digestion
The analyte may exist in forms that are not accessible to the chemical reaction for the
method. Metal ions can, for example, be bound to strong complexing agents, or be in
the wrong oxidation state. Phosphorus or nitrogen might not be available as molecular
building blocks for the respective detection response. Analyte bound in solids must be
transferred in solution before a wet-chemical analysis is carried out. In all these cases,
a so-called digestion precedes the actual analysis.
In each method description, carefully noted are things such as digestions, insofar as the
digestion reagents are part of the reagent sets. However, if, for example, undissolved
parts in a sample are to be analysed by a method that is intended to analyse clear solu-
tions, they must be analysed independently before the analysis.
Dilution of the original sample taking place as a result of a digestion procedure is taken
into account in the calculation of the final result.
If it is unknown is whether digestion is necessary (e.g. in the context of heavy metal
analysis), we recommend that you compare a digested sample analysis result with one
that is not. If the values are similar, no digestion is necessary. If the digested test shows
higher values, a digestion should be performed in the future. The knowledge gained
from this should be monitored occasionally.
EN Handbook of Methods
Sample
EN
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