On Monday, Colleen successfully defended her thesis titled “Developing Microfluidic Devices for the Optimization of Nanodiscs to Measure Membrane Protein Structure and Function."
In the coming weeks, Dr. Riordan will begin working at GlaxoSmithKline as an Investigator.
Congratulations and best wishes to Colleen from all of us in the Bailey Lab!!
Shannon successfully defended her thesis titled “Organic Phases in Microfluidic Systems: Enabling Real-Time Sensing of Small Molecules."
Dr. Quevedo will soon become Major Quevedo as she begins her tenure track faculty position at Virginia Military Institute this fall.
Congrats and best wishes to Shannon from all of us in the Bailey Lab!!
The zoom defenses continue! Today, John defended his thesis titled “New Interfaces to Silicon Photonic Microring Resonator Arrays for Chemical Separations."
Dr. Orlet will be starting the next phase of his career in a Scientist position at Bristol Myers Squibb.
Best wishes to John from all of us in the Bailey Lab!!
Current students Nick (3rd year), Claire (3rd year) and Krista (2nd year), along with Professor Bailey, virtually presented their work at Pittcon’s 2021 meeting. While the sights, sounds and tastes of NOLA were surely missed, there was no shortage of oral presentations, poster sessions, and fun excursions (via zoom) to fill up the week.
This week, in a virtual format, Cole defended his thesis titled “Clinical Diagnostics for Immune Response Assessment Through Multiplexed Biosensor Immunoassays In At-Risk Populations."
In March, Cole will continue his work with photonic-based diagnostics as a research scientist at SiPhox in Burlington, Massachusetts .
Congratulations to Dr. Chapman from all of us in the Bailey Lab!!
On Friday, Sara defended her thesis titled “Optimization of Nanodisc Array Generation on Silicon Photonic Microring Resonators for Lipid-Protein and Membrane Protein-Protein Interaction Characterization."
Next month, Sara will begin her career as a scientist at NGM Biopharmaceuticals in San Francisco, California.
Congratulations to Dr. Medfisch from all of us in the Bailey Lab!
In the Bailey Lab’s first virtual defense, Dr. Emily Mordan defended her thesis titled “Addressing Common HPLC Detector Challenges using Silicon Photonic Microring Resonators with Applications for Polymer Separations and More."
This January, she will begin her career at Dow, as a Senior Research Specialist in Analytical R&D!
Congratulations to Emily from all of us in the Bailey Lab!
Blood coagulation is regulated through protein-protein and protein-lipid interactions that occur at the sub-endothelium following vascular damage. Soluble clotting proteins bind to membrane components in a phosphatidylserine (PS) dependent manner to assemble multi-protein complexes that regulate clot formation; however, PS is of limited abundance physiologically. In this manuscript, we investigate synergy between PS and phosphatidylethanolamine (PE)-a lipid of much higher abundance naturally. Using a label-free, silicon photonic technology, we constructed arrays of Nanodiscs having variable lipid composition and probed the binding interactions of seven different clotting factors with GLA domains that have never been studied in tandem experiments before. The factors studied were prothrombin, activated factor VII, factor IX, factor X, activated protein C, protein S, and protein Z. Equilibrium dissociation constants (Kd) for each coagulation factor binding to Nanodiscs with unique compositions of PE and PS were determined. While all factors showed greater binding affinities in the presence of PS and PE, the most dramatic improvements in binding were observed when PS quantities were lowest. This demonstrates that synergy is effective in promoting coagulation factor binding under physiological lipid compositions, as opposed to the artificially high PS content probed in most in vitro activity studies.
Read the full article here!
Polymer brushes are found in biomedical and industrial technologies, where they exhibit functionalities considerably dependent on polymer brush–solvent–analyte interactions. It remains a difficult challenge to quickly analyze solvent-swollen polymer brushes, both at the solvent–polymer brush interface and in the brush interior, as well as to monitor the kinetics of interaction of solvent-swollen brushes with key analytes. Here, we demonstrate the novel use of silicon photonic microring resonators to characterize in situ swollen polymer brush–analyte interactions. By monitoring resonant wavelength shifts, we find that brush–solvent–analyte interaction parameters can be extracted from a single set of data or from successive analyte introductions using a single brush-coated sensor. The partition coefficient of three industrially relevant plasticizers into hydrophobic and hydrophilic brushes was determined and found to be in agreement with known solubility trends. We found that the diffusion coefficient of the plasticizer into the brush decreases as brush thickness increases, supporting a model of a dense inner brush layer and diffuse outer layer. pKa’s of pH-sensitive brushes were determined on the microring resonator platform; upon increasing the dry brush thickness, the pKa for poly(2-dimethylamino ethyl methacrylate) decreased from 8.5 to approach the bulk material pKa of 7.3 and showed dependence on the presence and concentration of salt. These proof-of-concept experiments show how the surface-sensitive nature of the microring resonator detection platform provides valuable information about the interaction of the polymer brushes with the solvents and analytes, not easily accessed by other techniques.
The 2020 Karle Symposium was held on July 31st. While in a virtual format this year, current students, alumni, faculty and outside researchers were still given the opportunity to learn about the novel research occurring in the chemistry labs here at UM. The Karle symposium is a yearly event named for Isabella and Jerome Karle, distinguished graduates of our department, who worked together to advance X-ray crystallography methods. Jerome Karle won the Nobel Prize in 1985 for their contribution to the field.
The Bailey lab was represented at the symposium in multiple formats. Rising third year, Nick Glenn, kicked off the student talks with his presentation titled: “Development of a Microfluidic Droptode for the Detection of Macromolecular Heparin”. Later in the day, rising third year, Claire Cook, presented in the analytical cluster’s poster session with a poster titled “Developing microfluidic tools to assess epigenetic heterogeneity among single cells”. Claire received a “Student Poster Presentation Award” sponsored by Dow for her work! Rising fourth year, Gloria Diaz, served on the symposium’s organizing committee team as a chair-elect, meaning she is set to chair the event with another graduate student in 2021.
The virtual event was filled with student talks, poster sessions, a PPG plenary lecture, and a Dow plenary lecture that highlighted collaborations with labs here in the chemistry department. The day concluded with the keynote lecture by Dr. Gabe Kwong of Georgia Tech and Emory School of Medicine titled “Chemical Approaches to Synthetic Immunity”. Great work to all of those involved in the symposium, especially to our lab-mates involved, and congratulations to Claire on her poster award!
