Fumonisins determination in urine by LC-MS-MS

The present work shows the optimization and validation results of an analytical methodology based on immunoaffinity clean-up (IAC) followed by liquid chromatography with tandem mass detection (LC-MS-MS) for the analysis of the mycotoxins fumonisin B(1) (FB(1)) and B(2) (FB(2)) in human urine samples, in order to evaluate fumonisins exposure in two Portuguese populations. As far as we know, immunoaffinity clean-up procedure was used, for the first time, in the analysis of fumonisins (FBs) in urine. Using this analytical methodology, the limit of quantification achieved was 10 ng mL(-1) for FB(1) and for FB(2). Recoveries were higher than 73.4% for fortification levels between 10 and 100 ng mL(-1) and intra-day and inter-day repeatability were lower than 8.6%. The natural occurrence of FB(1) and FB(2) in 68 human urine samples obtained from the central zone of Portugal was studied. None of the studied samples presented detectable levels of FB(1) and FB(2).