Analysis of Hydroquinone and 4-Methoxyphenol (Mequinol) on Zodiac HST OG

Hydroquinone (C₆H₄(OH)₂) is a dihydroxybenzene used in cosmetics, photography, and industrial applications. Mequinol (4-methoxyphenol, C₇H₈O₂) is a hydroquinone derivative that inhibits melanin synthesis by disrupting tyrosinase.

Both compounds can be retained, separated, and analyzed using a Zodiac HST OG mixed-mode stationary phase column. The analysis employs an isocratic method with a mobile phase of water, acetonitrile (MeCN), and sulfuric acid as a buffer, with UV detection at 300 nm.