single laboratory validation of a ready-to-use phosphatase inhibition assay for detection of okadaic acid toxins单实验室验证一个现成的磷酸酶抑制试验检测冈田酸毒素.pdf

Toxins 2012, 4, 339-352; doi:10.3390/toxins4050339 OPEN ACCESS toxins ISSN 2072-6651 /journal/toxins Article Single Laboratory Validation of A Ready-to-Use Phosphatase Inhibition Assay for Detection of Okadaic Acid Toxins Henry G. F. Smienk, Dolores Calvo, Pedro Razquin, Elena Domínguez * and Luis Mata Zeu-Inmunotec, Polígono PLAZA, C/Bari 25 Dpdo, 50197, Zaragoza, Spain; E-Mails: hsmienk@ (H.G.F.S.); dcalvo@ (D.C.); prazquin@ (P.R.); lmata@ (L.M.) * Author to whom correspondence should be addressed; E-Mail: edominguez@; Tel.: +34-976731533; Fax: +34976524078. Received: 31 January 2012; in revised form: 4 April 2012 / Accepted: 18 April 2012 / Published: 30 April 2012 Abstract: A phosphatase inhibition assay for detection of okadaic acid (OA) toxins in shellfish, OkaTest, was single laboratory validated according to international recognized guidelines (AOAC, EURACHEM). Special emphasis was placed on the ruggedness of the method and stability of the components. All reagents were stable for more than 6 months and the method was highly robust under normal laboratory conditions. The limit of detection and quantification were 44 and 56 µg/kg, respectively; both below the European legal limit of 160 µg/kg. The repeatability was evaluated with 2 naturally contaminated samples. The relative standard deviation (RSD) calculated was 1.4% at a level of 276 µg/kg and 3.9% at 124 µg/kg. Intermediate precision