title: Comparison of different sample treatments for the analysis of ochratoxin A in wine by capillary HPLC with laser-induced fluorescence detection.
abstract: Ochratoxin A (OTA) is a mycotoxin naturally found in various foods, including wine. As OTA is considered as a possible human carcinogen, the maximum concentration for this compound has been established at 2 μg kg(-1) in wine by the EU (Directive (CE) No 1881/2006). Typically, immunoaffinity columns have been used for its extraction. However, simpler, more efficient and less contaminant extraction systems are demanding. In this work, dispersive liquid-liquid microextraction using ionic liquid as extractant solvent (IL-DLLME) and the QuEChERS procedure, have been evaluated and compared for extraction of OTA in wine samples. Laser-induced fluorescence (LIF, He-Cd Laser excitation at 325 nm) coupled with capillary HPLC has been used for the determination of OTA, using a sodium dodecyl sulfate micellar solution in the mobile phase to increase the fluorescence intensity. Matrix-matched calibration curves were established for both methods, obtaining LODs (3× S/N) of 5.2 ng·L(-1) and 85.7 ng·L(-1) for IL-DLLME and QuEChERS, respectively. Clean extracts were obtained for white, rose and red wines with both methods, with recoveries between 88.7-94.2% for IL-DLLME and between 82.6-86.2% for QuEChERS. The precision was evaluated in terms of repeatability (n = 9) and intermediate precision (n = 15), being ≤ 8.5% for IL-DLLME and ≤ 5.4% for QuEChERS.
authors.affiliation: Department of Analytical Chemistry, Faculty of Sciences, University of Granada, Granada, Spain.
authors.forename: Natalia
authors.initials: N
authors.lastname: Arroyo-Manzanares
authors.forename: Ana M
authors.initials: AM
authors.lastname: García-Campaña
authors.forename: Laura
authors.initials: L
authors.lastname: Gámiz-Gracia
mesh_terms: D002138:Calibration; D002273:Carcinogens / Q000032:analysis; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005453:Fluorescence; D005506:Food Contamination / Q000032:analysis*; D006801:Humans; D007834:Lasers; D057230:Limit of Detection; D059627:Liquid Phase Microextraction / Q000379:methods*; D008823:Micelles; D009793:Ochratoxins / Q000032:analysis*; D015203:Reproducibility of Results; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000379:methods*; D014920:Wine / Q000032:analysis*
chemical_list: D002273:Carcinogens; D008823:Micelles; D009793:Ochratoxins; C025589:ochratoxin A; D012967:Sodium Dodecyl Sulfate