Validating chromatographic methods
The AOAC (15) has developed a Peer-Verified Methods validation program with detailed guidelines on exactly which parameters should be validated.Winslow and Meyer (16) recommend the definition and application of a master plan for validating analytical methods. Breaux and colleagues have published a study on analytical methods development and validation (17).For example, if the method is to be run on a specific instrument in a specific laboratory, there is no need to use instruments from other vendors or to include other laboratories in the validation experiments.In this way, the experiments can be limited to what is really necessary. Validation parameters for specific tasks The validation experiments should be carried out by an experienced analyst to avoid errors due to inexperience.Analytical methods need to be validated or revalidated The FDA has also published a guidance for the validation of bioanalytical methods (8). The report presents guiding principles for validating studies of both human and animal subjects.The most comprehensive document is the conference report of the 1990 Washington conference: Analytical Methods Validation: Bioavailability, Bioequivalence and Pharmacokinetic Studies, which was sponsored by, among others, the American Association of Pharmaceutical Scientists (AAPS), the AOAC and the U. The report has also been used as a basis for the FDA industry guidance document (8).
Final parameters should be agreed between the lab or analytical chemist performing the validation and the lab or individual applying the method and users of the data to be generated by the method.
It is not always necessary to validate all analytical parameters that are available for a specific technique.
For example, if the method is to be used for qualitative trace level analysis, there is no need to test and validate the method’s limit of quantitation, or the linearity, over the full dynamic range of the equipment.
Satisfactory results for a method can be obtained only with equipment that is performing well.
Special attention should be paid to those equipment characteristics that are critical for the method.