High-performance liquid chromatographic determination of low level uric acid in grains and cereal products as a measure of insect infestation

• Published in: Journal of Chromatography A 1983, Vol.269 (3), p.191-197
• Main Authors: Wehling, Randy L., Wetzel, David L.
• Format: Article
• Language: English
• Subjects: arthropod pests; Biological and medical sciences; Cereal and baking product industries; Control; Food industries; Fundamental and applied biological sciences. Psychology; Generalities; Insecta; Phytopathology. Animal pests. Plant and forest protection; plant biochemistry; plant physiology; plant products; Protozoa. Invertebrates; Records, symptoms, damages, economic importance, population surveys; storage pests; stored product protection
• ISSN: 0021-9673
• DOI: 10.1016/S0021-9673(01)90803-9

Uric acid, excreted by insects as an end product of nitrogen metabolism, is measured, with a detection limit of 1.0 μg uric acid/g sample, in grain and cereal products as an indication of contamination by stored product insects. The uric acid extracted from a cereal product sample into alkaline aqueous solution is analytically separated from other components in the extract by high-performance liquid chromatography. Ion-pairing with tetrabutylammonium ion in methanol—water is used on a reversed-phase column with detection at 280 nm. A column switching technique is employed to minimize analysis time. The method is linear over the range of interest, allowing quantitative and objective detection of infestation levels which may be encountered in commerce.