1. Direct determination of amino acids by hydrophilic interaction liquid chromatography with charged aerosol detection.
- Author
-
Socia, Adam and Foley, Joe P.
- Subjects
- *
HYDROPHILIC interaction liquid chromatography , *AMINO acid analysis , *GRADIENT elution (Chromatography) , *MOBILE phase (Chromatography) , *CHROMATOGRAPHIC detectors - Abstract
A chromatographic analytical method for the direct determination of amino acids by hydrophilic interaction liquid chromatography (HILIC) was developed. A dual gradient simultaneously varying the pH 3.2 ammonium formate buffer concentration and level of acetonitrile (ACN) in the mobile phase was employed. Using a charged aerosol detector (CAD) and a 2 nd order regression analysis, the fit of the calibration curve showed R 2 values between 0.9997 and 0.9985 from 1.5 mg/mL to 50 μg/mL (600 ng to 20 ng on column). Analyte chromatographic parameters such as the sensitivity of retention to the water fraction in the mobile phase values (m HILIC ) were determined as part of method development. A degradation product of glutamine (5-pyrrolidone-2-carboxylic acid; pGlu) was observed and resolved chromatographically with no method modifications. The separation was used to quantitate amino acid content in acid hydrolysates of various protein samples. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF