【摘要】 同步辐射共聚焦X射线荧光微探针技术(Synchrotron Radiation confocal micro X-ray Fluorescence,confocalμ-SRXRF)是一种具有深度分辨的三维元素分析方法,可以原位获得样品不同深度的化学元素信息,广泛应用于生命和环境原位研究领域。在上海同步辐射光源(Shanghai Synchrotron Radiation Facility,SSRF)硬X射线微聚焦及应用光束线站(BL15U1)搭建了共聚焦μ-SRXRF的实验装置和低温原位装置,并应用于生物样品体内化学元素分析。利用该装置对拟南芥种子和保持在低温环境中的大型蚤进行了原位荧光成像分析,无需切片及干燥过程直接获得了化学元素在样品体内的空间分布特征,并与常规μ-SRXRF获得的结果进行对比。实验结果表明:共聚焦μ-SRXRF可直接对生物样品体内的化学元素进行有效测量,同时联合低温原位装置可以扩展对热敏感的生物样品的化学元素分析,为生命和环境等研究领域提供强有力的原位表征技术。更多还原

【Abstract】 [Background] Synchrotron radiation confocal micro X-ray fluorescence(confocal μ-SRXRF) microprobe is a three dimensional analytical method for detecting chemical elements with depth resolution. It can be used to obtain the chemical element information at different depths of samples in situ, which is suitable in the fields of life and environmental sciences. [Purpose] This study aims to apply the confocal μ-SRXRF device and in-situ cryogenic device, developed at the hard X-ray micro-focusing beamline(BL15 U1) of Shanghai Synchrotron Radiation Facility(SSRF), to analyze the in vivo chemical elemental imaging of biological samples. [Methods] Confocal μ-SRXRF was based on K-B mirrors and polycapillary X-ray optics. The foci of the polycapillary X-ray optics and the incident X-ray beam were coincident by continuous scanning and position modification. The confocal μ-SRXRF was used for insitu XRF imaging analysis of Arabidopsis thaliana seeds and Daphnia magna, and compared with that of conventionalμ-SRXRF. The confocal volume was submerged at different depths within the samples to obtain the depth-dependent information. In addition, an in-situ cryogenic device was used to keep Daphnia magna under the cryogenic environment. [Results] The spatial distributions of chemical elements for in vivo biological samples were directly obtained by confocal μ-SRXRF, without slicing or drying. The specific distribution of chemical elements in plant tissues or organs is more accurately obtained while the absorption and distribution characteristics of chemical elements in organisms are observed more carefully. [Conclusions] Confocal μ-SRXRF can be used to directly and effectively analyze the spatial distribution of chemical elements within biological samples. Meanwhile, it can be expanded to analyze the heat-sensitive biological samples and chemical elements by equipping with in-situ cryogenic device, providing a powerful in-situ characterization technique for the life and environment research.更多还原