Linton R W, Walker S R, DeVries C R, Ingram P, Shelburne J D
Scan Electron Microsc. 1980(Pt 2):583-96.
The application of ion microanalysis (IMA) to the chemical characterization of freeze-fixed, freeze-dried cells is reviewed. Particular emphasis is given to pathological studies involving the determination of the chemical composition of isolated cells (e.g. rabbit alveolar macrophages--RAMs) exposed in vitro to toxic species (e.g. Pb3O4 particles). Ion microscopic results indicated that lead from Pb3O4 migrated into the RAMs and subsequently formed phosphorous-containing compounds. Quantitative comparisons of the relative concentrations of physiologic elements in Pb3O4-treated versus control RAMs also were made using ion microanalytical techniques. The Pb3O4 results illustrate that the three-dimensional analysis capabilities of the IMA may be exploited for the in situ observation of the penetration of xenobiotic agents into cell interiors and their subsequent intracellular chemistry. The potential advantages of ion microanalysis for the characterization of cells include high elemental sensitivity (including low atomic number elements and diffusible ions), broad elemental coverage, three dimensional analysis, and isotopic information. The major limitations include non-idealities of the ion sputtering process, the constraints on the lateral resolution available to identify subcellular features, and the difficulties inherent in the determination of absolute elemental concentrations.
本文综述了离子微分析（IMA）在冷冻固定、冷冻干燥细胞化学表征中的应用。特别强调了病理研究，这些研究涉及测定体外暴露于有毒物质（如Pb3O4颗粒）的分离细胞（如兔肺泡巨噬细胞——RAMs）的化学成分。离子显微镜结果表明，Pb3O4中的铅迁移到RAMs中，随后形成含磷化合物。还使用离子微分析技术对经Pb3O4处理的RAMs与对照RAMs中生理元素的相对浓度进行了定量比较。Pb3O4的结果表明，IMA的三维分析能力可用于原位观察异生物质进入细胞内部的渗透情况及其随后的细胞内化学过程。离子微分析在细胞表征方面的潜在优势包括高元素灵敏度（包括低原子序数元素和可扩散离子）、广泛的元素覆盖范围、三维分析和同位素信息。主要局限性包括离子溅射过程的不理想性、识别亚细胞特征时横向分辨率的限制以及绝对元素浓度测定中固有的困难。
