RESUMO
Homeopathic potencies 12cH and above cross the Avogadro number, and as such do not containany original drug molecules in their aqueous ethanol medium. It is thought H-bonded waterstructures preserved by ethanol carry the information of initial drug molecules. Potentized drugs show some differences with respect to their infrared (IR) absorption spectra. In a water-ethanol solution, free water molecules vary according to the concentration of ethanol. In the present study the concentration of ethanol has been kept constant at 0.03 molar fractions in 6 differenthomeopathic potencies. Aim: to see whether different homeopathic potencies having fixed ethanolcontent show variation in FTIR spectra and also free water molecules. Two potencies like 8cH and32cH of three homeopathic drugs Natrum mur, Cantharis and Nux vomica were used in thestudy, and their ethanol concentration was kept fixed at 0.03 molar fraction. The control wasconsidered to be aqueous ethanol at the same concentration. Spectrum of reference water wasalso taken. Fourier transform infrared (FTIR) absorption spectra were obtained in the wavenumber region of 4000 2800 cm-1. The half-width at half-maximum was measured for eachspectrum. The intensity of each spectrum was normalized at 3410 cm-1 close to the peak. The difference spectrum (absorbance of drug solution absorbance of reference water) for each drugand the control was obtained. FTIR spectra showed variation in absorbance intensity on both thehigh and low frequency side of the O-H stretching band in different drugs as well as the control. The C-H stretching band of 2977 cm-1 also showed variation in intensity in different drugs...