Measurements of the Elemental Distribution in Cells and Tissues by X-Ray Microanalysis

摘要: X-ray microanalysis has been used for several years studies of the elemental composition biological cells and tissues. The method is based on physical fact that an electron beam sufficient energy hitting matter excites X-rays. E, hence wavelength, these X-rays depends atomic number Z excited atoms according to Moseley’s law E∞Z 2. Elements are identified either by measuring characteristic wavelength means a crystal spectrometer or spectrum dispersive detector combined with multichannel analyzer. high resolving power microscope enables simultaneous imaging small structures at magnification analysis composition. However, application this samples complicated many problems involved in preparing specimen such way natural structure distribution remain intact vacuum conditions microscope. For reviews see, e.g., Hall [5], Hayat [7], Moreton [10], Goldstein et al. [2]. There variety different preparation instrumentation techniques available which have be chosen particular problem. Perhaps most powerful technique, even applicable diffusible elements spatial resolution, ultrathin cryosections scanning transmission [17]. This technique decribed here more detail. results discussed respect present possibilities limitations.