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Gregory A Cooksey

Optofluidic device
Credit: NIST
Our group designs and fabricates microfluidic devices with integrated optical waveguides to excite and collect light from materials in flow channels.  These systems are used to accurately measure very small volumetric flow rates (e.g. 10 nL/min) and to make highly reproducible measurements of single cells in flow.

Research Description

Microfluidic technologies support the manipulation and measurement of microscale quantities of material (e.g. cells, pharmaceutical drugs, and nanomaterials), which enables biomedical researchers and clinicians to conduct large numbers of miniaturized physical, chemical and biological studies simultaneously. The Biomedical Microtechnologies Group is working to facilitate reproducibility, improve detection limits, and expand the measurement capabilities of microfluidic technologies.  

Our current work, within the NIST on a Chip Program, includes developing microfluidic systems that improve the accuracy of flow measurements, which are fundamental to validating and maintaining the performance of microfluidic systems.  Using microfluidic devices with integrated optical waveguides, we have recently achieved dynamic measurements of 10 nL/min. We also have determined the uncertainty of zero flow, which means we can distinguish convection from diffusion (Cooksey et al. 2019).  

Building on that success, we are now creating optofluidic cytometry systems that enable better measurements of cells for medical diagnostics.  We aim to accelerate early disease diagnosis and drug discovery by improving measurement reproducibility and uncertainty quantification with novel system design and rigorous computational analysis. 

Research Opportunities Available.

Potential Research Topics include:

  • Optofluidic cytometry design and characterization
  • Flow metrology; working toward picoliter per minute measurements and dynamics
  • Microdroplet packaging and measurement
  • Rare event detection
  • Developing on-chip light sources and sensors
  • Physical modeling, e.g. of dynamic systems in flow
  • Cell-based microfluidic assays/diagnostics
  • Macro-to-micro connectivity / ease of use / Point-of-care delivery
  • Design of novel microfluidic functionalities

We encourage interested post-doctoral research candidates to contact us to discuss project opportunities and fellowships.  

Summer research opportunities for undergraduates (SURF Program) and high school students (SHIP Program) may also be available.  

Additional opportunities may also be available.  Please contact me for more details.

Our lab uses microvalves and channel design to dynamically control fluid flow and generate gradients.


The Art in Science of MicroTAS 2019†

Gregory A. Cooksey
The 2019 MicroTAS conference (the 23rd International Conference of Miniaturized Systems for Chemistry and Life Sciences) held in Basel, Switzerland, brought

The Art in Science of MicroTAS 2018

Gregory A. Cooksey
The 2018 MicroTAS conference (the 22nd International Conference of Miniaturized Systems for Chemistry and Life Sciences) took us to Kaohsiung, Taiwan, for an
Created September 24, 2019, Updated November 14, 2019