Nastaran Hashemi, William March Scholar in Mechanical Engineering, was chosen to receive the 2011 Naval Research Laboratory NRC/ASEE Research Publication Award for her paper “Optofluidic characterization of marine algae using a microflow cytometer.”
Hashemi, an American Society for Engineering Education (ASEE) Postdoctoral Fellow at the time, worked on the publication with Jeffrey Erickson, Joel Golden, and Frances Ligler from the Center for Bio/Molecular Science and Engineering at Naval Research Laboratory in Washington D.C.
The group demonstrated the design and fabrication of a flow cytometer, a device used to study microscopic particles, in a microfluidic platform, to characterize phytoplankton. Within the flow cytometer, streams of sheath fluid guided by grooves on a microchannel wrap around a central sample stream and hydrodynamically focus the sample stream in the center of the channel. Lasers provide excitation light close to the maximum absorbance wavelengths for the intrinsic chlorophyll and phycoerythrin within the phytoplankton, resulting in fluorescence and light scatter that are collected using optical fibers.
The team was able to detect and characterize picoplankton with diameter approximately 1 micrometer and larger phytoplankton of up to 80 micrometers in length. The wide range in size discrimination coupled with detection of intrinsic fluorescent pigments suggests that this microflow cytometer will be able to distinguish different populations of phytoplankton on unmanned underwater vehicles.
Their approach can be classified as optofluidics, a fast-growing field that complements microfluidic systems with optical functionality to construct highly integrated and compact “lab-on-a-chip” devices. “Optofluidic chips are more sensitive and provide higher throughput in a compact and cost-effective platform in comparison to conventional optical instruments,” Hashemi explained. “Optofluidic platforms such as sensors and flow cytometers can be used for environmental monitoring, medical diagnostics, and chemical-weapon detection.”
The work was published in Biomicrofluidics, and is one of a series of works published in Biosensors and Bioelectronics and Analytical Chemistry. It was also
- Selected for Publication in Virtual Journal of Nanoscale Science and Technology
- In the top 20 most read articles published in Biomicrofluidics for three months
- Resulted in more than 8 Invited Presentations and Talks
- Presented in Gordon Research Conferences – Microfluidics, Physics & Chemistry
The research publication award from NRL and ASEE honors bright, highly motivated, recent doctoral graduates for superior scientific accomplishments in areas of interest to the Navy. The award was given at the NRL Alan Berman Research Publication and Edison Patent Awards Ceremony in Washington, DC on March 16, 2012. Hashemi and Reza Montazami, assistant professor of mechanical engineering, were invited to the ceremony as guests of ASEE.