TITLE:
Determination of Alpha-Lipoic Acid in a Nutritional Supplement Using High Performance Liquid Chromatography
AUTHORS:
Trapali Maria, Fotia Eirini
KEYWORDS:
Alpha-Lipoic Acid, HPLC, Antioxidant Activity, Nutritional Supplement
JOURNAL NAME:
Journal of Diabetes Mellitus,
Vol.12 No.4,
November
7,
2022
ABSTRACT: Alpha lipoic acid has the ability to react and neutralize reactive oxygen species (ROS) such as superoxide radicals, simple oxygen, hydroxyl radicals, hypochlorous acid and peroxyl radicals. A rapid high-performance liquid chromatographic method for determination of lipoic acid in a nutritional supplement was developed. The method involved sample preparation and the mobile phase comprised of 50 mM disodium hydrogen phosphate buffer (pH 2.5 adjusted with 1 M H3PO4): acetonitrile in the ratio of 50:50. The separation was done using a C18 column (150 mm) and detection was carried out using UV detection at 201 nm. The assay was found to be linear in the range of 1.56 - 50 μg/mL with the correlation coefficient of 0.9997. Method precision was determined while LOD was 0.05 μg/mL and LOQ 0.15 μg/mL. The chromatographic peak LA retention time was 6 min.