The Fourier transform infrared spectroscopy (FTIR) of the policosanol nanoemulsion was performed according to the method described by Al-Qubaisi et al.41 (link) The spectra of one drop each of policosanol nonoemulsion, RBO and Tween 80; RBW and policosanol powder were recorded over the range of 400–4,000 cm−1 on a Thermo Nicolet Nexus, Smart orbit spectrometer, on spectroscopic-grade potassium bromide (KBr) with 10 tons of pressure.