Sample handling and pretreatment as critical points in determining the quality of analytical data during metallothionein determination in wild animals

摘要

Metallothioneins (MTs) are considered possible markers of environmental pollution, but pre-analysis handling of the tissues in which they are contained can affect their degradation. To determine MT synthesis in wild animals for the purpose of evaluating environmental pollution, the stability of MTs during animal trapping, during the transporting of samples to the laboratory, and during the storing of samples before analysis should be assessed. Five methods of pretreatment processing were tested on 12 male rats under laboratory conditions. MT concentrations were determined by differential pulse voltammetry (DPV) of the modified Brdiela reaction. The results show that freeze-drying does not affect the concentration of MTs in the tissue. However, the simulation of extreme field conditions resulted in a significantly lower concentration of MTs in analysed rat liver samples compared with normal conditions. Such samples could be excluded from further evaluation due to differences in the voltammetric recordings of the Brdicka reaction.