HPLC Separation of Phthalic Acids using Hydrogen Bonding


Phthalic acid, isophthalic acid and terephthalic acid are all isomers of each other. Being structurally similar, they can present difficulties to reverse-phase HPLC separation. Methods that require high organic concentrations in the mobile phase can cause dewetting in many reverse-phase columns. SHARC 1 column can be operated in anhydrous conditions and uses hydrogen bonding as the mechanism of separation. Here, phthalic acids were separated in pure acetonitrile (ACN), with the ability to adjust retention times by adding methanol (MeOH) to the mobile phase with formic acid and ammonium formate as buffer, making the method MS-compatible. Can also be UV detected at 270nm.


Column Sharc 1, 3.2×100 mm, 5 µm, 100A
Mobile Phase MeCN/MeOH
Buffer AmFm, Formic acid
Flow Rate 1.0 ml/min
Detection UV, 270 nm



Class of Compounds
Drug, Acid, Hydrophilic, Ionizable, Vitamin, Supplements
Analyzing Compounds Phthalic acid, Terephthalic acid, Isophthalic acid


Application Column


The SHARC™ family of innovative columns represents the first commercially available columns primarily utilizing separation based on hydrogen bonding. SHARC stands for Specific Hydrogen-bond Adsorption Resolution Column. Hydrogen bonding involves an interaction or attraction between a bound hydrogen atom and molecules containing electronegative atoms, such as oxygen, nitrogen, and fluorine.

Select options
Application Analytes:
Isophthalic acid
Phthalic Acid
Terephthalic Acid
SIELC Technologies usually develops more than one method for each compound. Therefore, this particular method may not be the best available method from our portfolio for your specific application. Before you decide to implement this method in your research, please send us an email to research@sielc.com so we can ensure you get optimal results for your compound/s of interest.