Brovedani Valentina, Sosa Silvio, Poli Mark, Forino Martino, Varello Katia, Tubaro Aurelia, Pelin Marco
Department of Life Sciences, University of Trieste, Via A. Valerio 6, 34127, Trieste, Italy.
U.S. Army Medical Research Institute of Infectious Diseases, Ft Detrick, MD, United States.
Toxicon. 2016 Sep 1;119:225-33. doi: 10.1016/j.toxicon.2016.06.013. Epub 2016 Jun 23.
Palytoxin (PLTX) and its analogues have been detected as seafood contaminants associated with a series of human foodborne poisonings. Due to a number of fatalities ascribed to the ingestion of PLTX-contaminated marine organisms, the development of methods for its detection in seafood has been recommended by the European Food Safety Authority (EFSA). Due to its feasibility, the spectrophotometric hemolytic assay is widely used to detect PLTX in different matrices, even though a standardized protocol is still lacking. Thus, on the basis of available assay procedures, a new standardized protocol was set up using purified human erythrocytes exposed to PLTX (working range: 3.9 × 10(-10)-2.5 × 10(-8) M) in a K(+)-free phosphate buffered saline solution, employing a 5 h incubation at 41 °C. An intra-laboratory characterization demonstrated its sensitivity (limit of detection, LOD = 1.4 × 10(-10) M and quantitation, LOQ = 3.4 × 10(-10) M), accuracy (bias = -0.8%), repeatability (RSDr = 15% and 6% for intra- and inter-day repeatability, respectively) and specificity. However, the standardized method seems not to be suitable for PLTX quantitation in complex matrices, such as mussel (Mytilus galloprovincialis) extracts, at least below the limit suggested by EFSA (30 μg PLTXs/Kg shellfish meat). Thus, the hemolytic assay for PLTX quantitation in seafood should be used only after a careful evaluation of the specific matrix effects.
岩沙海葵毒素（PLTX）及其类似物已被检测出是与一系列人类食源性中毒事件相关的海鲜污染物。由于摄入受PLTX污染的海洋生物导致了多起死亡事件，欧洲食品安全局（EFSA）建议开发在海鲜中检测PLTX的方法。尽管仍缺乏标准化方案，但由于其可行性，分光光度溶血测定法被广泛用于检测不同基质中的PLTX。因此，基于现有的检测程序，建立了一种新的标准化方案，该方案使用纯化的人红细胞，在无钾的磷酸盐缓冲盐溶液中暴露于PLTX（工作范围：3.9×10⁻¹⁰ - 2.5×10⁻⁸ M），在41°C下孵育5小时。实验室内部的特性表征证明了其灵敏度（检测限，LOD = 1.4×10⁻¹⁰ M，定量限，LOQ = 3.4×10⁻¹⁰ M）、准确性（偏差 = -0.8%）、重复性（日内和日间重复性的相对标准偏差分别为15%和6%）以及特异性。然而，该标准化方法似乎不适用于复杂基质（如贻贝（Mytilus galloprovincialis）提取物）中PLTX的定量，至少在EFSA建议的限量（30μg PLTXs/千克贝类肉）以下不适用。因此，在对特定基质效应进行仔细评估后，才可使用溶血测定法对海鲜中的PLTX进行定量。
