Zhang Ke, Liu Ruifeng, Irving Tom, Auld David S
Department of BCPS, Illinois Institute of Technology, BioCAT, 435B, APS, ANL, Argonne, IL 60439, USA.
J Synchrotron Radiat. 2004 Mar 1;11(Pt 2):204-8. doi: 10.1107/S0909049503028474. Epub 2004 Feb 12.
A low-temperature rapid-mixing and flow system has been designed and implemented to monitor catalysis involving metal ions by X-ray absorption spectroscopy at the ID-18 beamline of the Advanced Photon Source, Argonne National Laboratory. The system will allow examination of biological metallo-intermediates at dilute metal ion concentrations by the detection of X-ray fluorescence. The instrument can be cooled to sub-zero temperatures, thus lengthening the life time of a reaction intermediate. A portable UV-visible spectrometer is integrated with the flow system to monitor the sample optically. The system can also be used as a continuous-flow device to minimize radiation-induced sample damage by reducing sample exposure to the X-ray beam. The integration of the stop-flow instrument with the synchrotron beamline and X-ray fluorescence detector systems makes it unique for time-resolved X-ray absorption studies of dilute biological reactions. The results of the initial testing of the system are presented.
设计并实现了一种低温快速混合流动系统，用于在美国阿贡国家实验室先进光子源的ID-18光束线通过X射线吸收光谱监测涉及金属离子的催化作用。该系统将通过检测X射线荧光，在稀金属离子浓度下对生物金属中间体进行检测。该仪器可冷却至零下温度，从而延长反应中间体的寿命。一台便携式紫外可见光谱仪与流动系统集成，用于对样品进行光学监测。该系统还可作为连续流动装置使用，通过减少样品对X射线束的暴露，将辐射引起的样品损伤降至最低。将停流仪器与同步加速器光束线和X射线荧光探测器系统集成，使其在稀生物反应的时间分辨X射线吸收研究中独具特色。本文给出了该系统的初步测试结果。
