Validation of Analytical Methods Based on Chromatographic Techniques: An Overview

AbstractMethod validation is an important requirement in the analysis by liquid (HPLC) or gas (GC) chromatography. However, some analytical chemists seem unaware about its importance. They show serious doubt about the main aspects of validation: need, when it must be performed, its relationship with the development of the method and the correct procedure. Although a large number of indications and advices about validation can be found in the literature, they refer to specific methods, and are often underutilized. Several analysts consider that the validation must be mandatorily performed by a collaborative trial between several laboratories, and they are not willing to carry it out. A wide range of guidelines describing the parameters and indicating directives about the achievement of validation have also been issued. The understanding of the analysts about the process of method validation is inhibited because the terminology and methodology of the validation parameters depend on the scope and the guideline. The validation is applied with a specific objective, through a defined protocol, for the determination of a specific analyte inside an explicit working range. The validation should usually verify that the method effectively provides reliable results when applied to the predefined scope and using the established operating conditions. The scope of the analysis, a description of the analytical requirements needed to achieve the objectives of the analysis, must be clearly defined before starting the validation to select the adequate guideline and correctly conduct the validation process.This chapter describes the concept of method validation, referred to the analysis of organic compounds in liquid and gas chromatography. The need to establish the performances and the limits of a method and to evaluate its suitability for a specific purpose is revised. The increasing interest from researchers and regulatory agencies on validation during the past few years has been discussed by surveying the articles published and guidelines issued on this topic. Several approaches to correctly accomplish the validation have been detailed. Furthermore, the validation parameters, which should be evaluated, will be methodically described, and a thorough comparison between the main validation guides is provided.