Nano- and micro-structures occur abundantly in both the natural world and in synthetic materials, and their technological role is growing rapidly. The imaging of these small structures is difficult, as they are too small to see with the eye or ordinary optical microscope. Electron microscopes, which employ electrons instead of light for imaging, can achieve the necessary magnifications. With this award from the Major Research Instrumentation program, the University of Massachusetts Amherst Electron Microscopy Center is acquiring a scanning electron microscope with three unique features: (i) no requirement for exposing specimens to high vacuum, (ii) mitigation of the charge usually accumulated during imaging, and (iii) an integrated microtome. Amplifying on the latter, an integrated microtome allows serial sectioning of specimens as a means to gather a sequence of two-dimensional images that can be combined into a single, much more informative three-dimensional image. The instrument is a shared resource supporting research and teaching across campus as well as at several nearby undergraduate colleges. UMass Amherst has more than 50 vibrant funded research collaborations with U.S. companies, and many of these collaborations are being strengthened by the new capabilities to characterize specimens such as gels, emulsions, composites, adhesives, sensors, biological tissues, and individual cells. The Center has a strong track record in producing highly skilled microscopists, and the new instrument plays a central role in innovative undergraduate and graduate laboratory courses that afford hands-on training in electron microscopy, an expertise offered at few institutions in the nation.
With this award from the Major Research Instrumentation program, the University of Massachusetts Amherst Electron Microscopy Center is acquiring a Variable-Pressure Scanning Electron Microscope (VP-SEM) equipped with both a cryo-stage and a modular microtome for serial block-face imaging. The instrument operates at reduced pressure and provides gas injection for charge compensation, features that advance the imaging of insulating and/or solvated soft materials and life science specimens. In conjunction with advanced reconstruction software, the ultramicrotome will afford mapping in three-dimensions. As a field emission SEM with an energy-dispersive x-ray spectrometer, an added capability is three-dimensional elemental mapping. None of these capabilities was previously available in the Center. Together the new capabilities boost research directed at diverse topics such as: particle dynamics and structuring on non-volatile and modestly volatile liquids; morphologies of solvated films, membranes, and gels; and cell protein localization and neuron mapping. These projects span the campus and beyond, and users come from 20 or more University of Massachusetts Amherst departments as well as from 7 to 10 nearby colleges. Placed alongside an existing High-Resolution Field Emission Scanning Electron Microscope and an Energy-Filtered Field Emission Transmission Electron Microscope, the VP-SEM complements a strong suite of electron microscopy capabilities, furthering numerous individual research projects while sparking cross-pollination of ideas between materials and life science researchers. In addition to access through undergraduate and graduate courses, the VP-SEM will be available to users from collaborating U.S. companies, which number more than 50. In conjunction with other NSF-supported research projects at the University of Massachusetts Amherst, attractive images are being provided to Ventures in Science Using Arts Laboratory (VISUAL), an outreach effort that places these images, along with a laymen's explanation, in high track public venues.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
