Research Expertise & Professional Interests
Research in the Reinhard Lab focuses on new optical materials and their application to interrogate fundamental life processes. We are exploring the interface between nanotechnology and biological systems. For an overview of current research projects, please visit our group’s website. Recents techniques/materials developed in the Nano-Bio Interface Lab include:
Plasmon ruler RNase A cleavage assay: (A) The RNA plasmon rulers are bound to the surface of a glass flow chamber using a BSA (bovin serum albumin)-Biotin-NeutrAvidin surface chemistry. Upon addition of RNase A, the RNA tether is cleaved, and the dimer converted into a monomer. (B) Single RNA plasmon ruler cleavage trajectory (recorded at 96 Hz). (I) The plasmon ruler is first incubated in buffer containing spermidine at defined concentrations (0 -5 mM), (II) the buffer is exchanged with a 1 nM RNase A solution, causing (III) a strong drop in intensity upon RNA cleavage. Inset: Number of cleavage events for flushing with/without enzyme. ?tcl is defined as the time between enzyme addition and cleavage. For more information, refer to: L.R. Skewis & B.M. Reinhard, Nano Lett., 8, 214 (2008).
Plasmon Coupling Microscopy: Gold nanoparticle labeled surface receptors (left) and spectral signature (right) as function of interparticle distance. (a) For interparticle separations ? larger than the particle diameter D, the near-field interactions between the particles is small and the resonance wavelength ?res is that of an individual particle. (b) For interparticle separations ? < D the plasmons in the individual particles couple and the resonance wavelength ?res red-shifts with decreasing separation. This spectral shift is observable as an increase in the intensity ratio R = I580nm/I530nm.
Multiscale Nanoparticle Cluster Arrays (NCAs): SEM images from extracts of nanoparticle cluster arrays with varying diameters of e-beam defined binding size D = 50 nm (a), 80 nm (b), 100 nm (c), 130 nm (d), 200 nm (e). The SEM images confirm that through control of the diameter of the e-beam fabricated binding site the cluster size can be continuously varied. The enlargement of an individual cluster in (f) shows junctions and crevices between nearly touching particles constituting a high degree of roughness on the nanoscale.
The Reinhard group utilizes a variety of techniques including:
-Spectroscopy: Raman, SERS, Single Molecule Fluorescence, Plasmon
-Live Cell Imaging
-Transmission Electron Microscopy
-Scanning Electron Microscopy
-Cell Culture Facility
-Fluorescence Plate Readers
-The Photonics Center
-Center of Nanoscience and Nanobiotechnology
Cell Membrane Organization and Signaling