Validation of Chromatographic Methods of Analysis: Application for Drugs That Derived From Herbs.

It is well known that the quality control (QC) of drugs derived from herbs (DDHs) has two main problems: first, DDHs are chemically complex mixtures, and second, the chemical contents of raw plant materials are affected by the site of cultivation, age of plants, methods of harvesting, and processing. QC is used by manufacturers to ensure the consistency, safety, and efficacy of the DDHs. QC of DDHs can be performed by two approaches, namely, marker-oriented and chemical pattern-oriented (metabolite profiling) using chromatographic methods. For having reliable results of any chemical analysis that will be performed in the QC laboratory, the method of analysis must be validated first before it can be routinely applied. Parameters of the validation method that should be evaluated for marker-oriented approach are stability, selectivity, linearity, trueness, precision, and robustness/ruggedness, while for metabolite profiling approach stability, intra- and interday precisions should be determined. Determination of instrumental and sample detection limit (DL), quantification limit (QL), and cutoff value is described in this review. Some relatively new validation methods that could correlate trueness and precision will be also discussed. The importance and application of metabolite profiling for a QC laboratory at pharmaceutical industry are discussed.