Immuno‐ultrafiltration as a new strategy in sample clean‐up of aflatoxins

Abstract

The present paper describes the development of a new clean-up strategy for the analysis of aflatoxins (AFs) in food. The sample preparation method is based on immuno-ultrafiltration (IUF) which, in contrast to immunoaffinity chromatography, makes use of antibodies in free form. After selecting an appropriate ultrafiltration (UF) device and optimizing different operation conditions the IUF method was applied to the clean-up of maize and rice. Quantification of AFs was carried out by HPLC and fluorescence detection, after postcolumn derivatization in a Kobracell. The IUF method was shown to be as selective as sample clean-up using commercial immunoaffinity columns. Recovery rates and RSD for the AFs G(2), G(1), B(2) and B(1) in spiked rice were found to be 76 +/- 3, 76 +/- 2, 83 +/- 5 and 99 +/- 14%, respectively. The analysis of a FAPAS (food analysis performance assessment scheme) maize material resulted in AFs concentrations which were in the range assigned by the producer of the reference material.

Ultrafiltration liquid chromatography combined with high‐speed countercurrent chromatography for screening and isolating potential α‐glucosidase and xanthine oxidase inhibitors from Cortex Phellodendri

“…24 ppm (2H, t, J = 6 Hz, H-5) 13. C NMR (125 MHz, DMSO-d 6 ): ␦ 150.6 (C-10), 150.2 (C-3), 148.0 (C-2), 145.8 (C-8), 144.1 (C-9), 138.0 (C-13a), 133.4 (C-12a), 131.0 (C-4a), 127.2 (C-11), 123.8 (C-12), 121.8 (C-8a), 120.8 (C-13b), 120.5 (C-13), 108.8 (C-4), 105.9 (C-1), 62.3 (10-OCH 3 ), 57.4 (9-OCH 3 ), 56.6 (-OCH 2 O-), 55.4 (C-6), 26.7 ppm (C-5).…”

Towards biotracing in food chains

“…▪ Development in detection technologies for Salmonella, Bacillus, Clostridium, Norovirus, and extraction technology for S. aureus (Josefsen et al, 2007;Fach et al, 2009) ▪ Sampling strategies and innovative sampling technology for Salmonella, Campylobacter, B. cereus and B. anthracis (Reiter et al, 2009;Andersson and Haggblom, 2009) ▪ Mathematical modelling approaches and models developed, such as modular process risk modelling for Salmonella and domain models for S. aureus in milk and Salmonella in pork (Barker et al, 2009) ▪ Incorporation of field sampling data into models (Manios et al, 2009) ▪ Improved understanding of pathogen physiology and immobilised cells (Belessi et al, 2008).…”

Sampling Techniques for the Determination of Mycotoxins in Food Matrices

“…Finally, a new cleanup strategy based on immunoultrafiltration was applied, which, in contrast to immunoaffinity chromatography, makes use of antibodies in the free form and may have the potential advantage of being less expensive than the classical IAC: 170 in this case, sample extract, monoclonal antibodies anti-AFBs and PBST (phosphate buffer saline with tween 20, Sigma, St. Louis, MO, USA) were mixed in an ultrafiltration device, incubated in order to allow the formation of the antigen-antibody complex and then, after a washing steps, the mycotoxins were recovered performing the ultrafiltration with methanol: recovery rates are similar to what obtained with classical IAC, but potentially with lower costs.…”