Identification of medicinally active ingredients in ultradiluted Digitalis purpurea: FTIR and Raman spectroscopic studies

A systematic study of the effect of the commercially available, ultradiluted drug, Digitalis purpurea (extract of Foxglove leaves) with aqueous ethanol was conducted to monitor changes in its chemical structure/functional group arrangements using vibrational (Fourier Transform Infrared and Raman) spectroscopy. These changes suggest a significant effect of ultradilution (< micro volumes) in the spectrum profile of Digitalis bands in the fingerprint region. The study shows that the process of serial dilution assists in changing the chemical environment in the backbone matrix of the medicinally active ingredient of Digitalis purpurea. In particular, increase in dilution of Digitalis purpurea causes a change in its vibrational mode profile that matches well with the vibrational bands of digoxin. The technique seems to be useful in the detection and identification of compounds/chemical groups present at levels lower than microvolume in drugs used in alternative/complementary medicine.