I have tried PG, VG and Terpenes as liquidisers, but the best vape juice I have made, I simply didn't evaporate off all of the ethanol after winterising and it works a treat in Ccell cartridges. Since my ethanol is food grade and ethanol is sometimes used in the medical profession to administer inhaled medicine, the very tiny amount left in the oil should present no more health risk than the oil itself. It certainly tastes clean enough.