Stabilisotopenverdünnungsanalysen zur Quantifizierung organischer Spurenkomponenten in der Lebensmittelanalytik

Background and scope The principle and applications of stable isotope dilution assays (SIDAs) in food analysis is critically reviewed. This method is based on the application of internal standards labelled with stable isotopes. General topics The general section includes historical aspects of SIDAs, the prerequisites and limitations of the use of stable isotopically labelled internal standards along with possible calibrations procedures. The syntheses and availability of labelled food compounds for the use as internal standards is reviewed. Results The complete compensation for losses of analytes during clean-up as well as for ion suppression during LC-MS/MS and the so-called carrier effect are major advantages of SIDAs. However, deficient equilibration, spectral overlap and isotope effects can lead to false results. Discussion With regard to specificity and recovery, SIDAs generally are considered as the reference methods in clinical chemistry. In food chemistry, this method has been applied in flavour and pesticide analysis. However, it is becoming increasingly important also in the analysis of mycotoxins, further contaminants and vitamins. Conclusions The increasing access to isotopologic standards creates continuously new applications for SIDAs, particularly for bioactive compounds in foods.