Isotopic methods to detect food folates.

Abstract The bioavailability of folates from foods has become a popular area of interest. A common method of bioavailability measurement in human volunteers is using foods extrinsically and intrinsically labelled with stable isotopes. Chromatographic techniques such as high-performance liquid chromatography, gas chromatography or mass spectrometry are utilised for the separation and identification of folates from plasma and urine samples collected during dietary intervention, although most procedures at present are long winded and time consuming. This paper gives a short overview of the use of extrinsic and intrinsic labels for the use of studying folate absorption and metabolism. It also describes the production of an intrinsically labelled spinach for use in intervention studies, and discusses a simplified method for folate analysis and detection.