Completion of High Performance Scanning Ion Microprobe Upgrade

9317959利维-塞蒂芝加哥大学高分辨率扫描离子微探测器(UCSIM)的质量分辨能力和二次离子探测灵敏度的根本性升级即将完成。这一升级需要将微探头与高性能磁扇形质谱计对接，同时保留初级束流离子光学器件的卓越性能，并允许交替使用以前的RF四极质谱滤光器。尽管这一复杂升级所需的主要硬件和电子部件已经建成并投入使用，但新仪器开发的最关键阶段仍有待完成。在以前的预算限制下，最初被认为是次要优先事项的几个辅助设备的建造，现在被认为是对已经成功的仪器升级的一个有价值和必要的补充。最重要的是，微探头与高度精密的芬兰MAT化学质谱仪联合操作的复杂性需要广泛的优化和性能评估，以及对学生和工作人员的培训。正如我们仪器开发的前几个阶段所表明的那样，同时进行基础生物学研究一直是我们计划的最高优先事项之一。与几个学术机构的知名生物学家合作，高分辨率二次离子成像的系统研究和探索性应用已经产生了独特的结果，并在物理科学和生物科学之间建立了一个非常富有成效的接口。在业绩大大改善的情况下，将积极开展已经显示出希望的几项试点研究：(A)直接绘制标记的核苷在人类染色体中的分布图，并评估脆弱部位的核苷酸含量。(B)直接定位标记的核苷在果蝇中期染色体和多线染色体中的分布。(C)确定破骨细胞启动骨吸收的途径。骨形成和骨吸收中钙磷比的测定，将需要用钙同位素作为示踪剂的实验，以及磷的检测和测量。U~S t S%)~+*，。L cX3dhZ%I？-9317959 Levi-Setti的质量分辨能力和二次离子检测灵敏度的根本升级)u O！F K K；CG Times Symbol&amp；Arial 1 Courier 0 MS LineDraw E H：%：%F==抽象沙漠国王，BIR沙漠国王，BIR沙漠国王

9317959 Levi-Setti The radical upgrade of the mass discrimination capability and secondary ion detection sensitivity of the University of Chicago high resolution Scanning Ion Microprobe (UC SIM) is near completion. This upgrade has entailed the interfacing of the microprobe with a high performance magnetic sector mass spectrometer, while retaining the superior performance of the primary beam ion optics and allowing alternate use of the previous RF quadrupole mass filter. Although the principal hardware and electronic components needed for this complex upgrade have been constructed and are now operational, a most critical phase of new instrument development is still to be completed. The construction of several ancillary devices, originally deemed of secondary priority within the previous budgetary constraints, is now regarded as a worthwhile and necessary complement to the already successful instrumental upgrade. Most of all, the complexity of the joint operation of the microprobe with the highly sophisticated Finnigan MAT chemical mass spectrometer requires extensive optimization and performance evaluation, together with training of students and staff. As demonstrated in previous phases of our instrument development, the concurrent pursuit of fundamental biological studies has remained consistently one of the highest priorities of our program. In collaboration with established biologists from several academic institutions, systematic investigations and exploratory applications of high resolution secondary ion imaging have already yielded unique results and have created a very productive interface between the physical and the biological sciences. At a much improved level of performance, several pilot studies which already show promise will be actively pursued: (a) Direct mapping of the distribution of isotope labelled nucleosides in human chromosomes and evaluation of the nucleotide content of fragile sites. (b) Direct mapping of the distribution of isotope labelled nucleosides in Drosophila melanogaster metaphase and polytene chromosomes. (c) Identification of the pathways of bone resorption initiated by osteoclasts. Determination of the calcium to phosphorus radio in bone formation and resorption, This will entail experiments with Ca isotopes as tracers, and the detection and measurement of phosphorus. u ~ s t s % ) ~ + * , . g L c X 3 d h Z % i ? - 9317959 Levi-Setti The radical upgrade of the mass discrimination capability and secondary ion detection sensitivity of t u ) u O ! ! ! ! F K K ; CG Times Symbol & Arial 1 Courier 0 MS LineDraw E E h : % : % F = = abstract Deseree King, BIR Deseree King, BIR