HPLC Separation of Lactic Acid and Its Oligomers

Lactic acid (milk acid) is natural organic acid that plays an important role in biochemical processes. It has carboxylic and hydroxy-groups which upon standing can react with each other and form dimers, trimers and higher oligomers. Lactic acid is a polar molecule that produces no retention on reversed-phase column. Primesep B2 mixed-mode anion-exchange column is used for the separation of lactic acid and its oligomers by a combination of weak reversed-phase and anion-exchange mechanisms. Oligomers of lactic acid can be converted to lactic acid by hydrolysis. Primesep B2 column can be used for the analysis of lactic acid alone and lactic acid in the mixture of oligomers. Lactates can be monitored by low UV, ELSD or LC/MS. In case of ELSD, CAD or LC/MS, phosphoric acid in the mobile phase needs to be replaced with buffer compatible with these detection techniques (ammonium formate or TFA).


Column Primesep B2, 3.2×150 mm, 5 µm, 100A
Mobile Phase MeCN/H2O – 30/70%
Buffer H3PO4 – 0.1%
Flow Rate 0.5 ml/min
Detection UV 210 nm



Class of Compounds
Acid, Hydrophilic, Ionizable
Analyzing Compounds Lactic Acid


Application Column

Primesep B2

The Primesep family of mixed-mode columns offers a wide variety of stationary phases, boasting unprecedented selectivity in the separation of a broad array of chemical compounds across multiple applications. Corresponding Primesep guard columns, available with all stationary phases, do not require holders. SIELC provides a method development service available to all customers. Inquire about our specially-tailored custom LC-phases for specific separations.

Select options
Application Analytes:
Lactic Acid
Lactic Acid Oligomers
Organic Acids

Application Detection:
UV Detection
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.