Validation of liquid chromatography mass spectrometry (LC-MS) methods
1.1. The purpose of validation
Method validation is a key activity in chemical analysis and indispensable for obtaining reliable results. The higher the complexity of the method, the more important and voluminous, as a rule, is validation. Methods based on LC-MS are notorious for their complexity, on the one hand, because of the instrument itself and on the other hand, because LC-MS is often applied to the most complex samples. Therefore, it is important to demonstrate that methods are working as expected (validation) and that the obtained results are reliable. This information is relevant both to the laboratory (to be confident in your results or to make adequate changes in the method if the performance is not as expected) as well as to the customer. Besides the intrinsic necessity of validation, there are increasingly more regulations affecting laboratories that stipulate method validation as a requirement.
The importance of validation has led to the emergence of many validation guidance materials for laboratories, both of universal nature and sector-specific. Although there is a general agreement on the various validation parameters to be evaluated, diversity prevails about the details and about the methodology employed for validation and acceptance criteria: different recommendations and different sets of terminology are found in different guidelines. As a conclusion, the analytical chemistry community is still far from a consensus about exactly how validation should be carried out, both in general terms and as applied to LC-MS.
