HPLC Separation of Dihydroxybenzoic Acids on Newcrom B Column

High Performance Liquid Chromatography (HPLC) Method for Analysis of 2,3-Dihydroxybenzoic Acid , 2,4-Dihydroxybenzoic Acid , 2,5-Dihydroxybenzoic Acid , 3,4-Dihydroxybenzoic Acid , 3,5-Dihydroxybenzoic Acid , 2,6-Dihydroxybenzoic acid .

Dihydroxybenzoic acids are aromatic compounds consisting of a phenolic ring and a carboxylic acid. They all have the same chemical formula C7H6O4 .

The six main compounds are structurally similar and are difficult to separate in reverse-phase HPLC. The can be separated by using a mixed-mode Newcrom B column with the mobile phase having either methanol (MeOH) or acetonitrile (ACN) as an organic modifier having different retention characteristics. Using the gradient of organic modifier, water and sulfuric acid (H2SO4) as buffer, dihydroxybenzoic acids can be separated and UV detected at 250 nm.

You can find detailed UV spectra of 2,3-Dihydroxybenzoic Acid , 2,4-Dihydroxybenzoic Acid , 2,5-Dihydroxybenzoic Acid , 3,4-Dihydroxybenzoic Acid , 3,5-Dihydroxybenzoic Acid , 2,6-Dihydroxybenzoic acid and information about its various lambda maxima by visiting the following links for 3.4 DHBA , 3.5 DHBA , 2.4 DHBA , and 2.5 DHBA.