底栖甲藻-蛎甲藻属的扫描电镜样品制备方法

Preparation method of SEM sample suitable for benthic dinoflagellate—Ostreopsis

近十年来,全球海域由底栖甲藻引起的有毒有害赤潮频率和规模不断增加,严重威胁海洋生态安全和人类健康。底栖甲藻中蛎甲藻(Ostreopsis)是影响范围最广,危害最大的类群之一。本文通过使用四氧化锇、戊二醛和鲁格试剂进行单固定或双固定处理,并比较不同脱水时间,探讨适合蛎甲藻分类学研究的扫描电镜样品制备方法。结果表明:使用终浓度2.5%戊二醛或2%四氧化锇固定液单固定,梯度脱水时间为5 min,临界点干燥和喷镀,制备的蛎甲藻样品中细胞表面形态保存完好,壳板结构清晰。

In recent ten years,harmful algal blooms(HAB)caused by the benthic dinoflagellates have being increased frequently and severely.These HAB seriously threatened the marine ecological security and human health.The Ostreopsis species is one of the most notorious and harmful groups in benthic dinoflagellates.In this study,different treatments(a single or double fixation methods with different dehydration time)were carried out to detect their efficiency in fixing Ostreopsis spp.for scanning electronic microscopy(SEM).The results showed that the samples fixed with glutaraldehyde solution with a concentration of 2.5%or osmium tetroxide solution with a concentration of 4%,followed by a gradient dehydration time of 5 minutes,which was the best optimized treatment.The SEM images of Ostreopsis spp.under the best optimized treatment suggested that the Ostreopsis spp.cells were well fixed and the cell plate structures could be clearly observed.This study provided an effective preparation method for the observation of Ostreopsis under SEM.