Recent work by Associate Professor David Masiello and colleagues was highlighted in a November 7 article in Nature Photonics. The research was also highlighted in Chemical & Engineering News and in a News & Views feature article in Nature Photonics.
Measurement of the two distinct components—scattering and absorption—of a single nanoscale object’s optical extinction provides fundamentally important and complementary information on how that object processes light: either scattering it back to the far-field or converting it into internal excitation. Today, various techniques exist to measure the scattering from individual nanoscale objects, all relying on the detection of scattered photons in regions of zero background. Measuring their absorption, however, is much more complicated due to the fundamental inability to detect extremely small reductions in transmission over statistical fluctuations in the number of photons. This means that the spectroscopic signature of the vast majority of molecules—specifically, those that are transformed into dark states through photoreactions—is difficult to access.
To overcome this challenge, researchers in the Masiello group and the Goldsmith group at the University of Wisconsin–Madison devised a new experimental route to measure the absorption spectra of individual, nonemissive nanoscale objects by photothermal contrast in an optical microresonator cavity.
Photothermal spectroscopies function by inferring an object’s absorption from the localized temperature increase and resulting refractive index inhomogeneity produced by the excited object’s nonradiative decay. In their work, the team coupled individual plasmonic nanorods to an ultrahigh-quality optical microresonator cavity and succeeded in determining the nanorod’s absorption spectrum by monitoring the temperature-dependent attometer shifts in the resonance frequency of microresonator’s whispering gallery modes. These exceedingly small but detectable resonance shifts correspond to temperature increases of ~100 nK (measured at room temperature!), making their absorption spectrometer simultaneously one of the world’s best thermometers. Suprisingly, the nanorod’s absorption spectrum revealed a dense array of sharp Fano interferences arising from its interaction with the whispering gallery modes of the microresonator, allowing the team to deeply explore the hybridization of plasmonic and photonic cavity modes.
This collaborative effort brought together the creativity and talents of several graduate students and postdocs in multiple departments between the two institutions. The results were achieved following years of hard work involving both theorists and experimentalists. Future directions will explore the feasibility of this system to serve as a platform for studying quantum physics at room temperature.
To learn more about Professor Masiello and his research, visit his faculty page and research group website.
We are delighted to announce that Sotiris S. Xantheas has joined the Department as Affiliate Professor of Chemistry. He also holds the title of UW-PNNL Distinguished Faculty Fellow.
Dr. Xantheas is a Laboratory Fellow in Chemical Physics & Analysis, part of the Physical Sciences Division at Pacific Northwest National Laboratory. Dr. Xantheas is widely recognized for his expertise related to the molecular science of aqueous systems. His innovative studies of intermolecular interactions in aqueous ionic clusters and use of ab initio electronic structure calculations to elucidate their structural and spectral features are at the forefront of molecular theory and computation.
As Affiliate Professor of Chemistry with graduate faculty status, Dr. Xantheas is able to serve as a graduate advisor. Dr. Xantheas’ research facilities are located on the Pacific Northwest National Laboratory campus in Richland, WA.
For more information, please visit his faculty page, his PNNL staff page, or contact him directly via email at firstname.lastname@example.org.
The Biophysical Society has announced Professor Sarah Keller as the recipient of the 2017 Avanti Award in Lipids. Avanti Polar Lipids, Inc. established this annual award to be given by the Biophysical Society in recognition of an investigator’s outstanding contributions to understanding of lipid biophysics. Professor Keller will be honored at the Awards Symposium on February 14, 2017, during the Society’s 61st Annual Meeting in New Orleans.
In their announcement, the Biophysical Society stated that Professor Keller “is being recognized for her seminal work that has contributed to the understanding of phase behavior of multicomponent lipid membranes.” She is among the youngest recipients for this honor, in terms of years since Ph.D. at the time of award. Her numerous professional accolades include two previous BPS awards: the 2014 Thomas Thompson Award, which recognizes an outstanding contribution in the field of membrane structure and assembly, and the 2005 Margaret Oakley Dayhoff Award, which is given to a woman who holds very high promise or has achieved prominence while developing the early (pre-tenure) stages of a career in biophysical research.
Professor Keller is a biophysicist who investigates self-assembling soft condensed matter systems, primarily centered around how simple lipid mixtures within bilayer membranes give rise to complex phase behavior. In addition to her primary work in Chemistry, she is also Adjunct Professor of Physics, and previously served as Associate Dean for Research Activities in the College of Arts and Sciences.
For more information about Professor Keller and her research, please visit her faculty page and her research group website.
Congratulations to Assistant Professor Joshua Vaughan and his UW co-workers, whose recent work was featured on the cover of Nature Methods. Their report details the development of a simplified method to “inflate” cellular structures for use in an imaging technique known as expansion microscopy.
Efforts to improve the resolution of cellular structures typically focus on addressing the limitations of microscope hardware. With expansion microscopy, higher resolution is achieved through physical alteration of the specimen. By linking swellable polymers to customized fluorophores, researchers can physically expand the specimen to enable super-resolution microscopy with a conventional laboratory microscope.
As noted in the journal, Vaughan and co-workers have “developed and characterized new methods for linking fluorophores to the polymer that now enable expansion microscopy with conventional fluorescently labeled antibodies and fluorescent proteins.” By simplifying the procedure and expanding fluorophore options, they came up with separate approaches to provide high resolution imaging of individual cells and of tissue slices. In addition to facilitating a range of biological studies, these refinements broadly expand access to the technique, enabling researchers to use a variety of conventional fluorophores and ordinary laboratory microscopes to achieve high resolution cellular imaging.
More information about this work can be found in Nature Methods and in the UW News press release.
For more information about Professor Vaughan and his research, please visit his faculty page and research group website.
Assistant Professor AJ Boydston has been named a 2016 Camille Dreyfus Teacher-Scholar by The Camille and Henry Dreyfus Foundation. The Camille Dreyfus Teacher-Scholar Awards Program supports the research and teaching careers of talented young faculty in the chemical sciences. Based on institutional nominations, the program provides discretionary funding to faculty at an early stage in their careers. Criteria for selection include an independent body of scholarship attained within the first five years of their appointment as independent researchers, and a demonstrated commitment to education, signaling the promise of continuing outstanding contributions to both research and teaching. The Camille Dreyfus Teacher-Scholar Awards Program provides an unrestricted research grant of $75,000.
To learn more about the Camille Dreyfus Teacher-Scholar Awards Program, please visit the Dreyfus Foundation website. To learn more about Prof. Boydston, please visit his website and research group page.
The Department of Chemistry congratulates Senior Lecturer Deborah Wiegand on her promotion to Principal Lecturer, effective September 16, 2016.
Dr. Wiegand joined the Department of Chemistry as Lecturer in 1990, and was promoted to Senior Lecturer in 1995. From 2001-2013, she served as Director of Academic Counseling and the UW Gateway Center and then as Assistant Dean for Undergraduate Academic Affairs, making wide-ranging contributions to student welfare and improving undergraduate services and education.
Dr. Wiegand returned to Chemistry full-time in 2013 as Senior Lecturer and Director of Entry-Level Programs. She regularly teaches courses in our introductory-level general chemistry sequence and serves as the sole instructor for our General, Organic, and Biochemistry sequence, which targets students preparing for the study of nursing. As Director of Entry-Level Programs, Dr. Wiegand leverages her previous administrative experience to provide critical leadership for our large introductory-level instructional programs. Her administrative contributions include leading a significant revision of our introductory-level general chemistry curriculum and the development of a placement test for introductory chemistry courses; when fully implemented, these will help us to better educate and serve the thousands of students who take our introductory-level courses each year.
The Department of Chemistry congratulates Lecturer Colleen Craig on her promotion to Senior Lecturer, effective September 16, 2016.
Dr. Craig joined the regular faculty of the Department of Chemistry as Lecturer in Autumn 2012 after serving as an instructor for general chemistry courses since Autumn 2009. She typically teaches Introduction to General Chemistry and multiple courses in the introductory-level general chemistry sequence, and she contributes in-depth knowledge about online learning and assessment systems. For her efforts to incorporate innovative technology in the classroom to enhance student learning and engagement, Dr. Craig was one of four Chemistry team members to receive the 2015 Distinguished Teaching Award for Innovation with Technology.
The Department of Chemistry congratulates Lecturer Jasmine Bryant on her promotion to Senior Lecturer, effective September 16, 2016.
Dr. Bryant joined the regular faculty of the Department of Chemistry as Lecturer in Autumn 2012, though she has previously contributed to the Department in both instructional and administrative capacities. She is unusually versatile as an instructor, successfully teaching large lecture courses in 100-level introductory general chemistry and 200-level sophomore organic chemistry, as well as 300-level inorganic chemistry lecture and laboratory courses. For her efforts to incorporate innovative technology in the classroom to enhance student learning and engagement, Dr. Bryant was one of four Chemistry team members to receive the 2015 Distinguished Teaching Award for Innovation with Technology.
Robert Synovec, Professor and Associate Chair for Graduate Education, is the recipient of the 2016 Marcel Golay Award. The Marcel Golay Award was created by PerkinElmer in honor of Marcel Jules Eduard Golay, the inventor of capillary columns. It is presented to a scientist in recognition of a lifetime of achievement in capillary chromatography. Prof. Synovec is being recognized for his “outstanding investigations in the areas of complex mixture analysis, multidimensional chromatography instrumentation design, and chemometrics uses for analytical separations.” The award will be given at the 40th International Symposium on Capillary Chromatography, in Riva del Garda, Italy, May 31- June 3, 2016.
To learn more about Professor Synovec and his research, visit his faculty page and research group site.
Assistant Professor Brandi Cossairt has received a CAREER (Faculty Early Career Development) Award from the National Science Foundation. The CAREER Program is a Foundation-wide program that “offers the National Science Foundation’s most prestigious awards in support of junior faculty who exemplify the role of teacher-scholars through outstanding research, excellent education and the integration of education and research within the context of the mission of their organizations.” Professor Cossairt received the award for her research proposal, “CAREER: New Models for Controlling InP Nucleation, Growth, and Luminescence using Magic-Sized Clusters and Targeted Surface Chemistry”. Research conducted under this CAREER award aims to address the fundamental challenges in controlling the composition and interfaces of nanomaterials with atom-level precision. Experimental approaches include:
1) testing new models of InP nucleation using isolable, structurally characterized and atomically precise magic-sized cluster intermediates;
2) understanding how surface chemistry impacts the structure and function of InP magic-sized clusters to gain access to general strategies for anisotropic shape control and doping; and
3) discovering new post-synthetic surface chemistry to turn-on and color-tune the luminescence of InP and related QDs using Lewis acid coordination chemistry.
Additionally, the project aims to advance educational goals, including creating an undergraduate specialization in Chemistry for Energy at the University of Washington (UW), developing hands-on demonstration materials and workshops on the topic of colloidal nanoscience targeted to middle and high school students in collaboration with the UW Phi Lambda Upsilon (National Chemistry Honor Society) chapter, and broadening participation in chemistry at the undergraduate, graduate and professional level through work with several organizations.
For more information about this NSF CAREER Award, please visit the award website.
For more information about Brandi Cossairt and her research program, please visit her faculty page and research group site.