Solid-phase extraction of ochratoxin A from wine based on a binding hexapeptide prepared by combinatorial synthesis

In this paper we describe the preparation of a hexapeptide library by combinatorial synthesis and the identification of a peptide with sequence Ser-Asn-Leu-His-Pro-Lys, which showed good affinity (K-eq = 3.4 x 10(4)M(-1)) towards the mycotoxin ochratoxin A (OTA). An immunoaffinity-like stationary phase supporting such a hexapeptide was used to develop a solid-phase extraction method for the quantification of OTA in wine samples at concentration levels down to 0.10 mu g 1(-1). Several different wine samples fortified with OTA at 2 and 4 mu g1(-1) levels showed recovery of 94.7% and 98.4% at 2.0 and 4.0 mu g 1(-1), respectively, without any effect on the extraction efficiency of the matrix. The efficacy of this approach was successfully tested by comparison with an immunoaffinity extraction performed on commercial, cartridges. (c) 2007 Elsevier B.V. All rights reserved.