In detail

UV-VIS is fast and inexpensive, and it is widely used for family totals such as silymarin, total polyphenols, and flavonoid content. The sample absorbs light at a selected wavelength, and the concentration is calculated from a calibration curve built with a reference standard.

The limitation is specificity. UV can count compounds that are not the marker you care about, and colour or turbidity can interfere. A UV silymarin result of 80% and an HPLC silybin result measure different things. Neither is automatically wrong, but they cannot be compared directly, and the certificate should name the method.

Why it matters to a buyer

  • Many market-standard specifications are still written on a UV basis.
  • It explains why a UV value can look higher than an HPLC value for the same material.
  • It is useful for rapid screening, but weaker for specific label claims.

What to ask a supplier

01

At which wavelength and against which reference standard was the result measured?

02

Is the result as-is or on a dry basis?

03

Do you also have an HPLC result for the specific compound on the label?

Cite this page

Rainwood Botanical. "Ultraviolet-visible spectroscopy." Botanical extract glossary, October 2026. https://ingredients.rainwoodbio.com/resources/glossary/uv-vis/