Simultaneous determination by liquid chromatography/mass spectrometry of five low calorie intense sweeteners in urine: a potential biomarker approach for assessing intakes

Low calorie intense sweeteners (LCS) are food additives whichare commonly used as sugar substitutes in a variety of products in order toprovide a sweet taste without increasing the energy content. Methods ofmonitoring exposure to these compounds can be prone to error and giventhat several LCS are excreted via the urine largely un-metabolised(1-3), anopportunity exists to implement a biomarker approach for investigatinglevels of exposure more objectively. Simultaneous analysis of various LCShas been carried out in various foodstuffs(4) and waste water(5). No suchmethod, however, has been published for urine. Objectives: This projectaimed to develop a method for the simultaneous determination of four LCS(acesulfame-K, saccharin, cyclamate, sucralose) and the excretory productof a relatively new sweetener, steviol glycosides (steviol glucuronide), inhuman urine. Materials and Methods: Liquid chromatography withmass spectrometry was utilised in order to separate and quantify the fivecompounds of interest. A simple sample preparation procedure, consistingof a 10-fold dilution followed by filtration, was used. Method validationinvolved the assessment of linearity & range, limits of detection (LOD) andquantification (LOQ), as well as accuracy and precision (intra-batch and interday)which were assessed at three concentrations across the dynamic range(12.5, 550 and 930ng/ml). Results: Very good linearity was observed for allfive LCSs across a large dynamic range of 10-1000ng/ml (R2 0.997-0.999) with