Mobilization and analytical availability of drug residues in food.

A complete mobilization of veterinary drug residues for quantitative analytical detection is often unsuccessful. For some drugs, one reason for this is the quite different binding forms between the drug and the food matrix, which for three groups of veterinary drugs may be described by sorption-isothermals. The influence of glutathione on sorption-isothermals and residue mobilization is discussed. Thus, better interpretations regarding the availability of residues are possible.