Trace elements in sediments and bioaccumulation in European silver eels (Anguilla anguilla L.) from a Mediterranean lagoon (SE Italy)

Samples of surface sediments and tissues (liver and muscle) of commercially available European silver eels (Anguilla anguilla L.) collected from Varano lagoon (Italy) were analysed to determine trace element contents. Univariate and multivariate analyses were performed to highlight both the differences between sampling sites and the influence of channel discharges. Atomic ratios indices for sediment data and biological enrichment factors (BEF) for eel tissues were calculated in order to evaluate the enrichment factor due to human activities. The highest levels of As (11.9?µg?g^?1) and Zn (14.1?µg?g^?1) were observed in the south-eastern zone of the lagoon, which is influenced by urban and agricultural discharges. The low levels of Hg observed in this study (0.04?µg?g^?1) led us to exclude both natural and human local sources of this element. Trace element concentrations of all elements were lower in muscle than in liver tissue. Significant enrichment of Cu and Zn was found in livers.     

高效液相色谱-串联质谱法同时测定鳗鱼和虾中残留的33种喹诺酮和磺胺类药物

建立了鳗鱼和虾中33种喹诺酮类(QNs)和磺胺类(SAs)药物残留量的高效液相色谱-串联质谱(HPLC-MS/MS)测定方法。以氘代试剂为内标,样品经酸性乙腈萃取后,用正己烷脱脂,旋转蒸发浓缩,采用LC-MS/MS选择反应监测(SRM)正离子模式测定,同时对鳗鱼和虾中的33种QNs和SAs进行定性和定量。33种QNs和SAs的检出限(S/N=3)为1.0 μg/kg,定量限(S/N=10)为2.0 μg/kg;在10.0～200.0 μg/L时目标物的峰强度与质量浓度的线性关系良好(r>0.99);平均回收率为66%～123%。该法简便快捷,降低了分析成本,也在一定程度上实现了药物残留的快速检测。     

LC-MS-MS测定烤鳗中4种氟喹诺酮药物残留量

应用LC—MS—MS技术,建立了快速准确测定烤鳗中4种常见的氟喹诺酮药物残留量的方法,样品经简单的溶剂提取后即可上机测定,在10～50μg／kg范围内添加回收率良好,检出限10μg／kg．本文还讨沦了流动相以及质谱碰撞能对4种氟喹诺酮药物的质谱行为的影响,并借助准MS—MS—MS技术探讨了氟喹诺酮药物的质潜碎片产生机理。     

用原位杂交技术检测二价染色体上黄鳝rRNA基因多态性的研究

用地戈辛标记的原位杂交技术研究黄鳝二价体上ｒＲＮＡ基因的多态性．共检测到：数目和位置多态；杂交信号形态多态；ｒＲＮＡ基因的联合现象；７号二价体上可移动的ｒＲＮＡ基因位点；ｒＲＮＡ基因的串联重复；ｒＲＮＡ基因杂交信号周围的微信号密集等６种多态现象．还对本研究结果进行了详细地讨论．