Matrix effect and recovery terminology issues in regulated drug bioanalysis.
Understanding the meaning of the terms used in the bioanalytical method validation guidance is essential for practitioners to implement best practice. However, terms that have several meanings or that have different interpretations exist within bioanalysis, and this may give rise to differing practices. In this perspective we discuss an important but often confusing term - 'matrix effect (ME)' - in regulated drug bioanalysis. The ME can be interpreted as either the ionization change or the measurement bias of the method caused by the nonanalyte matrix. The ME definition dilemma makes its evaluation challenging. The matrix factor is currently used as a standard method for evaluation of ionization changes caused by the matrix in MS-based methods. Standard additions to pre-extraction samples have been suggested to evaluate the overall effects of a matrix from different sources on the analytical system, because it covers ionization variation and extraction recovery variation. We also provide our personal views on the term 'recovery'.
Drug Studies Unit, Department of Bioengineering & Therapeutic Sciences, University of California, San Francisco, CA 94143, USA. yong.huang@ucsf.edu
Yong
Y
Huang
Robert
R
Shi
Winnie
W
Gee
Richard
R
Bonderud
D002851:Chromatography, High Pressure Liquid / Q000592:standards; D006461:Hemolysis; D008055:Lipids / Q000737:chemistry; D004364:Pharmaceutical Preparations / Q000032:analysis* / Q000592:standards; D011786:Quality Control; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry / Q000592:standards; D009626:Terminology as Topic
D008055:Lipids; D004364:Pharmaceutical Preparations