title: Determination of fumonisins B1 and B2 in corn-based foods for infants and young children by LC with immunoaffinity column cleanup: interlaboratory validation study.
abstract: A liquid chromatographic method for the determination of fumonisins B1 (FB1) and B2 (FB2) in corn-based foods for infants and young children was subjected to an interlaboratory validation study involving 11 laboratories. Five blind duplicate sample pairs of each matrix were analyzed to establish the accuracy, repeatability, and reproducibility of the method. Mass fractions in the baby food samples ranged from 89.1 to 384.4 microg/kg FB1 and from 22.5 to 73.6 microg/kg FB2. The method involved a warm extraction with citrate phosphate buffer-methanol-acetonitrile (50 + 25 + 25, v/v/v), a cleanup through an immunoaffinity column, and an end-determination of fumonisins by LC after automated precolumn derivatization with o-phthaldialdehyde reagent. RSDs for within-laboratory repeatability (RSDr) ranged from 6.8 to 23.5% for FB1 and 7.6 to 22.9% for FB2. RSDs for between-laboratory reproducibility (RSDR) ranged from 15.4 to 26.2% for FB1 and 21.6 to 36.3% for FB2. Mean FB1 recoveries from baby foods spiked at 100.0 and 250.0 microg/kg were 89 and 96%, respectively; for FB2 spiked foods at 25.0 and 62.5 microg/kg recoveries were 90 and 85%, respectively. HorRat values ranged from 0.8 to 1.2 for FB1, whereas for FB2 they ranged from 0.9 to 1.4 when calculated according to Horwitz, and from 1.0 to 1.7 when calculated according to Thompson, indicating an acceptable among-laboratory precision for all matrixes (HorRat values <2).
authors.affiliation: Institute of Sciences of Food Production, National Research Council of Italy, Via Amendola, 122/0-70126 Bari, Italy. michele.solfrizzo@ispa.cnr.it
authors.forename: Michele
authors.initials: M
authors.lastname: Solfrizzo
authors.forename: Annalisa
authors.initials: A
authors.lastname: De Girolamo
authors.forename: Lucia
authors.initials: L
authors.lastname: Gambacorta
authors.forename: Angelo
authors.initials: A
authors.lastname: Visconti
authors.forename: Joerg
authors.initials: J
authors.lastname: Stroka
authors.forename: Hans P
authors.initials: HP
authors.lastname: Van Egmond
mesh_terms: D002138:Calibration; D002675:Child, Preschool; D002845:Chromatography / Q000379:methods*; D002853:Chromatography, Liquid / Q000379:methods*; D005504:Food Analysis / Q000379:methods; D005506:Food Contamination; D037341:Fumonisins / Q000737:chemistry*; D006801:Humans; D007223:Infant; D007225:Infant Food / Q000032:analysis*; D007753:Laboratories / Q000592:standards; D015203:Reproducibility of Results; D003313:Zea mays / Q000737:chemistry*
chemical_list: D037341:Fumonisins; C056934:fumonisin B2; C056933:fumonisin B1