Quantitative Analysis of Cardiac Glycosides in Digitalis purpurea and Digitalis lanata with HPLC

Cardiac glycosides have a successful track record in the treatment of heart failure. The glycosides digoxin and digitoxin are extracted from the plant species Digitalis purpurea and Digitalis lanata and increase cardiac function and circulation. These glycosides act by binding cellular membranes and inhibiting the Na+/K+ pump. There is a substantial body of knowledge surrounding blood serum levels of these compounds but little is known about their concentrations in Digitalis and the factors that affect these concentrations. The purpose of this work was to establish an optimized protocol for quantification of both digoxin and digitoxin within Digitalis. The compounds were extracted from leaf samples with water and methanol and characterized by HPLC at a wavelength of 220 nm using a three part mobile phase consisting of 10% acetonitrile, 60% methanol, and 30% water. Future work involves cultivation of Digitalis species under various conditions to determine the factors that affect digoxin and digitoxin concentration and in vivo testing of these compounds