Modern electron microscopy permits scientists to study the fine detail of cells and tissues, using both two-dimensional and three-dimensional imaging modalities. However, achieving optimal preservation of ultrastructure for a variety of biological samples remains a challenge. Here, we describe practical methods to preserve the fine structure of mouse skeletal muscle and sciatic nerve and to obtain high-resolution images of mitochondria in cultured cells, flow-sorted T-cells, and mouse urothelium. We also propose an effective and economical workflow for three-dimensional electron microscopy in the context of a microscopy core facility.

The rapid progress in the performance of today's sophisticated transmission electron microscopes also demands computational and educational tools capable of simulating the intricacy of electron image formation. The tools ideally should be widely accessible to the microscopy community and capable of covering both the breadth and depth demanded by modern materials science. Here, a cloud-based microscopy simulation platform, called cloudEMAPS and powered by cloud computing and modern server-client web programming architecture, is described. Compared to the current desktop solutions for electron microscopy simulations, cloud computing offers the unique advantages of on-demand, data sharing, high-performance computation and internet easy access using the state-of-the-art web infrastructure. This article will demonstrate these advantages using examples of interactive simulations of electron diffraction patterns and aberration-corrected electron optics.

In-situ transmission electron microscopy (TEM) provides an avenue to explore time-dependent nanoscale material changes induced by a wide range of environmental conditions that govern material performance and degradation. The In-situ Ion Irradiation TEM (I3TEM) at Sandia National Laboratories is a JEOL 2100 microscope that has been highly modified with an array of hardware and software that makes it particularly well suited to explore fundamental mechanisms that arise from coupled extreme conditions. Examples pertaining to multibeam ion irradiation, rapid thermal cycling, and nanomechanical testing on the I3TEM are highlighted, along with prospective advancements in the field of in-situ microscopy.

The development and implementation of high-stability monochromators in state-of-the-art aberration-corrected scanning transmission electron microscopes has enabled materials characterization with an energy resolution as good as 3 meV. This allows the vibrational modes, which would otherwise be obscured by the energy spread of the electron beam, to be probed with very high precision in molecular materials. Since the vibrational energies depend on the weight of the atomic nuclei, vibrational spectroscopy can distinguish isotopes whose only difference lies in their neutron content. This opens up isotopic analysis and mapping in transmission electron microscopy as two important new research areas. Here, we review the monochromated electron energy loss spectroscopy (EELS) instrumentation, discuss optimal methods for probing beam-sensitive materials without destroying them, and review key nanoscale isotope-resolved results.

Recent years have seen increased crossover of microscopy techniques developed for transmission electron microscopes (TEMs) being utilized as well in scanning electron microscopes (SEMs). The order of magnitude lower beam energies available in SEMs correspond with significantly different beam-sample interactions that must be accounted for when examining freestanding films. This is especially important for composition analysis via energy dispersive X-ray spectroscopy (EDS) since lower-energy transmission experiments mean X-ray volumes become comparable to sample dimensions. To better understand this scenario, we report results of an SEM-EDS study of terraced freestanding films comprising binary compounds with well-defined atomic ratios. Guided by Monte Carlo simulations, EDS line scan data were collected at different beam energies across segments of varying thicknesses. The results of quantification analysis using different models are compared for multiple combinations of beam energy, sample thickness, and material density, from which some general guidelines are provided for SEM-EDS analysis of freestanding films.

The CytoViva Enhanced Darkfield (EDF) Illuminator enables direct optical observation of nano-scale entities in a wide range of transparent and translucent sample environments, without requiring the use of labels or other markers. The improved performance is a result of a uniquely designed light path, which focuses maximum photon density on the sample, thus enabling superior signal-to-noise imaging performance. This high-performance capability not only provides users with previously unobtainable images, but it also allows established techniques such as hyperspectral and Raman microscopy to be used in new and exciting ways.