title: Simultaneous determination of ochratoxin A and cyclopiazonic, mycophenolic, and tenuazonic acids in cornflakes by solid-phase microextraction coupled to high-performance liquid chromatography.
abstract: A solid-phase microextraction (SPME) method, coupled to liquid chromatography with diode array UV detection (LC-UV/DAD), for the simultaneous determination of cyclopiazonic acid, mycophenolic acid, tenuazonic acid, and ochratoxin A is described. Chromatographic separation was achieved on a propylamino-bonded silica gel stationary phase using acetonitrile/methanol/ammonium acetate buffer mixture (78:2:20, v/v/v) as mobile phase. SPME adsorption and desorption conditions were optimized using a silica fiber coated with a 60 microm thick polydimethylsiloxane/divinylbenzene film. Estimated limits of detection and limits of quantitation ranged from 3 to 12 ng/mL and from 7 to 29 ng/mL, respectively. The method has been applied to cornflake samples. Samples were subjected to a preliminary short sonication in MeOH/2% KHCO(3) (70:30, v/v); the mixture was evaporated to near dryness and reconstituted in 1.5 mL of 5 mM phosphate buffer (pH 3) for SPME followed by LC-UV/DAD. The overall procedure had recoveries (evaluated on samples spiked at 200 ng/g level) ranging from 74 +/- 4 to 103 +/- 9%. Samples naturally contaminated with cyclopiazonic and tenuazonic acids were found; estimated concentrations were 72 +/- 9 and 25 +/- 6 ng/g, respectively.
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Bari, Via E. Orabona 4, I-70126 Bari, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Aresta
authors.forename: Nicola
authors.initials: N
authors.lastname: Cioffi
authors.forename: Francesco
authors.initials: F
authors.lastname: Palmisano
authors.forename: Carlo G
authors.initials: CG
authors.lastname: Zambonin
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D007211:Indoles / Q000032:analysis*; D009173:Mycophenolic Acid / Q000032:analysis*; D009793:Ochratoxins / Q000032:analysis*; D013720:Tenuazonic Acid / Q000032:analysis*; D003313:Zea mays / Q000737:chemistry*
chemical_list: D007211:Indoles; D009793:Ochratoxins; C025589:ochratoxin A; D013720:Tenuazonic Acid; D009173:Mycophenolic Acid; C000543:cyclopiazonic acid