Dr. Sara Brenner
Associate Professor of Nanobioscience
Assistant Vice President for NanoHealth Initiatives
College of Nanoscale Science and Engineering, SUNY Polytechnic Institute
Over the last five years, the CytoViva enhanced darkfield microscope with hyperspectral imaging (EDFM-HSI) has become an
integral part of our team’s research portfolio in nanobioscience. The system is extremely valuable in advancing our work in numerous areas including occupational health and safety, environmental health, toxicology, public health, and medicine. The CytoViva system allows us to visualize, identify, and semi-quantitate engineered nanomaterials (ENMs) in complex matrices, such as biological or environmental media, and provides unique images and data at the nanoscale. For example, we use it to analyze histological tissues from animal toxicology studies, airborne nanoparticulate captured on filter media from workplaces, complex industrial wastewater streams, and various raw nanomaterials. It has proven especially useful in areas where conventional tools, such as electron microscopy, are too slow, costly, and cumbersome for routine analysis. The speed and utility of EDFM-HSI is a key advantage over other modalities, and it holds tremendous potential in terms of rapid, high-throughput sample screening.
In order to create accurate reference spectral libraries (RSLs), particularly for sample sets that lack a true positive control, we have utilized Raman spectroscopy (RS) to confirm the identity of the ENMs before creating an RSL from the RS-verfied particles. For us, that means taking a sample from the CytoViva scope to a Raman tool in a different lab in a different building on our campus, then beginning the tedious process of locating the same area within the sample for RS analysis. This has literally cost my team years of productivity on specific projects. To have an integrated CytoViva EDFM-HSI/RS system would be enormously beneficial, as it would significantly expedite sample analysis and reduce errors that could be made going when moving the sample between tools in different physical locations. In reality, for many types of complex real-world samples for which the system is poised to analyze, this capability will be critical as it would allow for rapid ENM identification within samples in combination with direct visualization – this would provide crucial data, which is extremely costly and time-consuming to acquire through the use of other currently available modalities.
Roth GA, Sosa Peña M del P, Neu-Baker NM, Tahiliani S, Brenner SA. Identification of Metal Oxide Nanoparticles in Histological Samples by Enhanced Darkfield Microscopy and Hyperspectral Mapping. Journal of Visualized Experiments : JoVE. 2015;(106):53317. doi:10.3791/53317
Additional Featured Publications
Sosa Peña MP, Gottipati A, Tahiliani S, Neu-Baker NM, Frame MD, Friedman AJ, Brenner SA. Hyperspectral imaging of nanoparticles in biological samples: simultaneous visualization and elemental identification. Microscopy Research and Technique 2016. Early view published online.
Guttenberg, M., Bezerra, L., Neu-Baker, N. M., del Pilar Sosa Idelchik, M., Elder, A., Oberdörster, G. and Brenner, S. A. (2016), Biodistribution of inhaled metal oxide nanoparticles mimicking occupational exposure: a preliminary investigation using enhanced darkfield microscopy. J. Biophoton, 9: 987–993. doi:10.1002/jbio.201600125
Roth, G. A., Tahiliani, S., Neu-Baker, N. M. and Brenner, S. A. (2015), Hyperspectral microscopy as an analytical tool for nanomaterials. WIREs Nanomed Nanobiotechnol, 7: 565–579. doi:10.1002/wnan.1330
Dr. Andrij Holian
Department Biomedical and Pharmaceutical Sciences
Center for Environmental Health Sciences
University of Montana
We are writing this letter to describe the benefit of the CytoViva technology and the great support we have received from the CytoViva team.
We purchased the instrumentation in July 2014. Since then we have used the darkfield and hyperspectral imaging (HSI) to detect particles in both tissue sections and cultured cells. We have successfully imaged metals such as gold and silver in addition to metal oxides like titanium dioxide and nickel oxide using ‘spectral angle mapping’ techniques. In contrast, this did not work well with our main particle of interest, multi-walled carbon nanotubes. Fortunately, CytoViva developed an alternative called ‘spectral feature fitting’ that does work well with these difficult to image particles. We are about to submit our first paper using this technique for MWCNT and it was indispensable for the work we were doing. This could not have happened without the strong support from the CytoViva team. We want to acknowledge not only that unique capability of the instrumentation, but also the continued support that we continue to receive from CytoViva long after our purchase.
The CytoViva has generated a lot of interest with other investigators to the point that we have to schedule users and training on the instrument. We look forward to adding Raman capability. This is one of the best instrument purchases we have made, as it fits so well with our research missions.
Robert Vince, PhD
Director, Center for Drug Design (CDD)
University of Minnesota
I am writing this letter to offer a testimonial to the unique value the CytoViva Enhanced Darkfield/Hyperspectral Imaging system has brought to my laboratory at the Center for Drug Design at the University of Minnesota.
We have used the system extensively since first purchasing in 2009. One of the more prominent example projects involved our work on the early detection of Alzheimer disease via spectral imaging of specific beta amyloid proteins. We leveraged the optical imaging and spectral analysis capabilities of the CytoViva system to first verify the existence of these proteins in retinal tissue of deceased Alzheimer patients. We then progressed to doing the same in the blood stream of genetically engineered mice (ex-vivo via the blood vessels in the retina) and are now testing this same process on live test patients. The CytoViva Enhanced Darkfield/Hyperspectral Imaging system was key in identifying the spectral signals of the targeted proteins in retinal tissue samples which set the stage for later tests on the vascular structure of the retinal in live subjects. CytoViva, Inc. also helped develop customized imaging tools for examining the retinas of live mice ad human test subjects.
This is just one example if the utility of this system in our research and development efforts here at the University of Minnesota. We anticipate many more similar examples of the success in the future.
Dr. Vladimir V. Tsukruk
Regents Professor and Dean’s Professor of Engineering
School of Materials Science and Engineering
Georgia Institute of Technology
The Cytoviva hyperspectral instrument has allowed our lab capabilities to expand dramatically. Single particle studies, easy swapping between fluorescence and dark field measurements, and software ease of use allow us to collect results that would have taken much longer with other available instruments. This instrument sees high demand constantly from researchers both inside and outside of our group, and it has been our best purchase in recent years.
Dr. Melissa Vetten
School of Materials Science and Engineering
NIOH, South Africa
The Toxicology Department at the National Institute for Occupational Health (NIOH) purchased a CytoViva HSI system in 2011. We have always had a very good working relationship with the CytoViva team who have always been helpful, providing prompt support when it came to technical issues with the system and guidance when it came to bench top preparation of samples.
The CytoViva system is used extensively in our department to investigate the uptake and toxicity of micro- and nano-particles, of both incidental and engineered origins. The enhanced darkfield microscopy provides a quick and easy method to assess uptake of particulates into cells in vitro. The system has also been used on in vivo samples to assess the localization of nanomaterial in lung tissue slices and ecotoxicological samples (Zebra fish, Daphnia). The hyperspectral imaging feature and spectral angle mapping has enabled us to positively identify nanoparticles in our samples without fluorescent labelling or tedious TEM preparation. Results from these projects have been published in International Peer Reviewed journals.