... the anhydrous,ethanol-free substance.Specific Absorbance: 300-355 at 349nm,calculated on the anhydrous, ethanol-free substance.Light- ... absorbing Impurities: Not more than 0.07 at 490nm,calculated on the anhydrous,ethanol-free substance.Related Substances ... ,calculated on the anhydrous, ethanol-free substance. Shold any business opportunity arise, please feel free to let us know. We ...