Capillary electrophoresis as a fast and efficient alternative for the analysis of Urceola rosea leaf extracts

Urceola rosea, a plant whose leaves are used as food and for medical purposes, is a climbing liana found in many south-east Asian countries. Main polar compounds are flavonoids (kaempferol and quercetin glycosides) and phenolic acids. As an alternative to the established HPLC method their analysis by capillary electrophoresis is described for the first time. It was possible in <8min with a 25mM sodium tetraborate decahydrate solution with pH8.5, at a capillary temperature of 40°C and an applied voltage of 25kV. Up to five compounds could be quantified in different methanolic U. rosea extracts, which showed to be of variable composition; e.g. the content of total flavonoids ranged from 0.29 to 1.08%. In respect to quantitative results as well as validation parameters (e.g. R²≥0.994, recovery rates from 95.5 to 103.6%, inter-day precision≤4.5%) the CE method was well comparable to HPLC. However, in terms of required analysis time and environmental sustainability capillary electrophoresis is definitely advantageous.