Conference will begin: Tuesday, October 26, 2021 - 8:00 AM EDT
Presented by: Euan McLeod, University of Arizona
Many biomedical diagnostics require quantifying levels of specific protein molecules in blood, saliva, or other bodily fluids. Antigen tests for COVID-19 are a recent example. Lens-free holographic microscopy has been applied to many bioimaging tasks because it is compact, inexpensive, and can image an ultra-large field of view with submicron resolution. However, it has not previously been applied to protein sensing in solution. In this talk McLeod demonstrates the application of lens-free holographic microscopy to the sensing of specific proteins in aqueous solution, in an approach his group calls quantitative large area binding (QLAB).
In QLAB, beads coated with receptors for the target protein are imaged, and the bead clustering that results when the target protein is present is quantified using automated image processing. McLeod and his team use biotin-coated beads to sense dissolved NeutrAvidin and antibody-coated beads to sense dissolved interferon gamma, which is a cytokine molecule that is a biomarker for inflammatory and infectious diseases. Limits of detection are in the ng/mL (or hundreds of pM) range. The group believes this QLAB sensor will be useful for rapid and low cost field-portable or point-of-care diagnostics.
About the presenter
Euan McLeod, Ph.D., is an Associate Professor in the Wyant College of Optical Sciences at the University of Arizona (UA). He joined UA's faculty in 2015. He is also an Associate Professor of the UA BIO5 Institute and an Affiliate Member of the UA Cancer Center. He is a Senior Member of the Optical Society of America and won an NSF CAREER award in 2021. He was previously a postdoc in Electrical Engineering and Bioengineering at UCLA, as well as a postdoc in Applied Physics at Caltech. He received his Ph.D. from Princeton University and his B.S. from Caltech. His background and interests lie at the intersection of optics, nanoscience, and soft bio-materials science. He has published more than 35 papers on these topics in peer-reviewed journals, with major contributions in the areas of high-speed varifocal lenses based on acoustic modulation; lens-free holographic imaging of nanoparticles, viruses, and biomarkers; and the use of optical tweezers in fabricating micro- and nano-structured materials.