Single-Molecule Vibrational Thermometry.

Molecular probes of temperature (termed "molecular thermometers") have become broadly used for temperature measurements. Here, we describe Boltzmann-edge vibrational thermometry (BET) detected by anti-Stokes fluorescence, where the relative population of vibrationally excited molecules acts as a calibration-free reporter of local temperature based on the Boltzmann distribution. We demonstrate that BET microscopy is readily compatible with biological samples and achieves single-molecule sensitivity.

Two-dimensional bond-selective fluorescence spectroscopy: violations of the resonance condition, vibrational cooling rate dispersion, and super-multiplex imaging.

Multidimensional spectroscopies have shaped our understanding of molecular phenomena, but they are often limited in sensitivity. In this work, we describe two-dimensional bond-selective fluorescence-detected infrared-excited (2D-BonFIRE) spectro-microscopy: an ultrasensitive two-dimensional spectroscopy and hyperspectral imaging technique. 2D-BonFIRE spectra are richly detailed, allowing for direct measurement of vibronic coupling and strong evidence of combination modes in congested spectral regions.

Drug delivery agent that acts as a drug for synergistic activity.

Drug delivery vehicles increase cell permeability of their cargo, but otherwise are expected to be inert. In developing a potential strategy to treat myotonic dystrophy type 1, we developed a delivery vehicle that was designed to be a direct acting drug. The oligomeric delivery agent selectively targets the expanded DNA and RNA repeat sequences (d(CTG) and r(CUG)) that cause DM1.

Single-Cell Metabolic Imaging Reveals Glycogen Driven-Adaptations in Endothelial Cells.

Endothelial dysfunction (ED) is a defining feature of diabetes mellitus (DM) and a key contributor to many metabolic and cardiovascular diseases. Endothelial cells (ECs) are known to be highly glycolytic and primarily rely on glucose to meet their energy demands. However, the role of glycogen metabolism in ECs remains poorly characterized due to a lack of suitable tools.

Subtleties of nanophotonic lithium niobate waveguides for on-chip evanescent wave sensing.

Thin-film lithium niobate (TFLN) is promising for optical sensing due to its high nonlinearities, but its material properties present unique design challenges. We compare the sensing performance of the fundamental modes on a TFLN waveguide with a fluorescent dye sample. The TM mode has better overlap with the sample, with a 1.

Room-Temperature Single-Molecule Infrared Imaging and Spectroscopy through Bond-Selective Fluorescence.

Infrared (IR) spectroscopy stands as a workhorse for exploring bond vibrations, offering a wealth of chemical insights across diverse frontiers. With increasing focus on the regime of single molecules, obtaining IR-sensitive information from individual molecules at room temperature would provide essential information about unknown molecular properties. Here, we leverage bond-selective fluorescence microscopy, facilitated by narrowband picosecond mid-IR and near-IR double-resonance excitation, for high-throughput mid-IR structural probing of single molecules.

Nitrile Vibrational Lifetimes as Probes of Local Electric Fields.

Optical measurements of electric fields have wide-ranging applications in the fields of chemistry and biology. Previously, such measurements focused on shifts in intensity or frequency. Here, we show that nitrile vibrational lifetimes can report local electric fields through ultrasensitive picosecond mid-infrared-near-infrared double-resonance fluorescence spectro-microscopy on Rhodamine 800.

Progress Toward a Multiomic Understanding of Traumatic Brain Injury: A Review.

Traumatic brain injury (TBI) is not a single disease state but describes an array of conditions associated with insult or injury to the brain. While some individuals with TBI recover within a few days or months, others present with persistent symptoms that can cause disability, neuropsychological trauma, and even death. Understanding, diagnosing, and treating TBI is extremely complex for many reasons, including the variable biomechanics of head impact, differences in severity and location of injury, and individual patient characteristics.

Portable Waveguide-Based Optical Biosensor.

Rapid, on-site diagnostics allow for timely intervention and response for warfighter support, environmental monitoring, and global health needs. Portable optical biosensors are being widely pursued as a means of achieving fieldable biosensing due to the potential speed and accuracy of optical detection. We recently developed the portable engineered analytic sensor with automated sampling (PEGASUS) with the goal of developing a fieldable, generalizable biosensing platform.