Matrix effects in (ultra)trace analysis of pesticide residues in food and biotic matrices

If one has to determine multiple residues of modern pesticides and/or other groups of (semi)polar and/or thermally unstable contaminants with a wide range of physico-chemical properties within a single analytical run, it can be complicated to obtain low limits of quantitation (LOQ), good precision as well as relevant trueness of results for all the target analytes. Matrix components, which are unavoidably present in analyzed samples (even after the thorough clean-up step), may be responsible for miscellaneous adverse affects impairing different stages of the GC and/or LC determinative step. In this review, the nature of various types of matrix effects are discussed together with suggestions for prevention, reduction and/or compensation of their occurrence when determining troublesome analytes in foods and other complex biotic matrices.