1.1 INTRODUCTION Essential to the study of navonoids is having the means available for their separation analytical and preparative) and isolation The importance of this aspect of flavonoid research can be seen in the number of review articles that refer to their chromatography. %However, the information is usually spread out over chapters in books or occurs in isolated sections devoted to individual classes of these polyphenols This chapter. therefore. aims to present a brief unified summary of general techniques. with reference to the different categories of structure flavones and flavonols and their glycosides). isoflavones, flavanones chalcones, anthocyanins. and proanthocyanidins. In earlier times. thin-layer chromatography (TLC). polyamide chromatography. and per electrophoresis were the major separation techniques for phenolies. Of these methods. LC is still the workhorse or navonoid analysis. It is used as rapid. simple, and versatile a method for following polyphenols in plant ewracts and in fractionation work. However, the majority of published work now refers to qualitative and quantitative applications of high- performance liquid chromatography HPLC for analysis Flavonoids ean be separated