Seeing something as small as a nanometer—just about three to five atoms wide—requires highly advanced imaging techniques.
Confocal image. Top: Mutant Drosophila adult testis showing germ cells (red) and cell surface and fusome (green). Bottom: Early stage (third larval instar) wild-type (normal) Drosophila testis showing germ cells (red) and cell surface and pigment cell nuclei (green). Credit: Van Doren Lab/JHU
Faculty affiliated with Johns Hopkins University’s Institute for NanoBioTechnology and researchers from a wide range of disciplines across divisions at JHU will find advanced, comprehensive, and highly precise methods of imaging at the Integrated Imaging Center (IIC) at JHU’s Homewood Campus.
Everyone is invited to see firsthand what IIC has to offer at the center’s annual open house, co-sponsored by Carl Zeiss and FEICO, on Sept. 21, 2007 from 3 to 6 p.m. IIC’s 2,500 square-foot facility is located on the first floor of Dunning Hall.
IIC’s facilities help scientists and engineers characterize nanomaterials at very small length scale as well as biologists studying complex cellular and subcellular interactions. Microscopy services at IIC also aid developers of medical applications investigate the interface between materials and biological systems and basic biomedical researchers describe nano-sized drug delivery systems.
The center boasts more than $3.5 million worth of state-of-the-art imaging equipment, including one of only two uniquely configured laser scanning microscopes in the United States. The goal of IIC, says center director J. Michael McCaffery, an associate research professor in the Department of Biology, is to provide the Johns Hopkins community, as well as other academic institutions, industry, and government, with resources for both conventional and advanced methods of light and fluorescence microscopy services.
Confocal image. Developing embryo of C. elegans. PIE-1 protein tagged with green fluorescent protein to monitor asymmetric cell division. Credit: Wirtz Lab/JHU
“As rapid advances have been made in the development of new techniques of fluorescence and electron microscopy, visualization and localization of biomolecules at the light and electron microscope level has become an essential component of any comprehensive study of molecular cell biology,“ McCaffery says. “This is because light and electron microscopy observations provide detailed information on the distribution, movement, and interaction of biomolecules or proteins within the cell that cannot be obtained by other methods.“
To anticipate the changing demands of research in a variety of disciplines, McCaffery says, IIC has added new equipment in recent months. A highlight includes a Zeiss laser scanning microscope (LSM) 510 VIS confocal with a Confocor 3 fluorescence correlation spectroscopy (FCS) module.
“There is only one other system of its kind in the U.S. that combines the FCS with confocal imaging and that is capable of cross-correlation,“ McCaffery says. “FCS allows for high-resolution spatial and temporal analysis of single biomolecules with respect to diffusion, binding, and enzymatic reactions in vitro and in vivo.“
Other new additions include a FEI Tecnai 12 TWIN 120kV high resolution (
Transmission electron miscroscope (TEM) image of self-assembled monolayer of spherical cobalt nanoparticles (~12 nm diameter) from a solution of hexane/octadecene. Credit: Searson Lab/JHU
The ESEM has proved to be very popular, McCaffery says, because of its ability to “image fully hydrated/wet samples with minimal preparation.“ In traditional scanning electron microscopy, samples must be dehydrated and coated with a metal prior to imaging. In the ESEM mode, McCaffery explains, “you can use a peltier stage to achieve relative humidity at any temperature or pressure in order to image live samples with minimal surface tension induced drying artifacts.“
The center features five suites devoted to specific imaging functions. These include a ultramicrotomy/tissue culture/cell prep room; a wet laboratory; “scanning room,“ which includes the Quanta ESEM and Typhoon phosphorimager; a transmission electron microscopy suite with two TEMs; and a multifunctional light microscopy suite, which includes the Marians 4D LM, Zeiss LSM 510 VIS confocal with Confocor 3 FCS, LSM 510 META UV confocal, and two Zeiss epifluorescence microscopes. Knowledgeable IIC staff members are available to answer questions or assist with the use of all equipment. Grants from the National Institutes of Health, National Science Foundation, and Howard Hughes Medical Institute help fund the additions to IIC.
Confocal image. Observation of green fluorescent nanoparticles (~90 nm in diameter) traveling through a micropost obstacle course. Credit: Drazer Lab/JHU
The Homewood campus IIC was established in 1998. Additional advanced imaging services have been available at the Montgomery County Campus IIC since 2004.
To learn more about the Integrated Imaging Center at JHU or to schedule an appointment to use the facilities, please go to the IIC Web site: http://www.jhu.edu/~iic/.
To view images from the IIC, click on the following link: http://www.jhu.edu/iic/gallery.htm
For other JHU research facilities visit our facilities page: http://inbt.jhu.edu/facilities.php