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De-Hao D. Tsai, Frank W. DelRio, Sherrie R. Elzey, Suvajyoti S. Guha, Michael R. Zachariah, Vincent A. Hackley, Melanie P. Shelton
Dithiothreitol (DTT)-based displacement is widely utilized for separating ligands from their gold nanoparticle (AuNP) conjugates, a critical step for differentiating and quantifying surface-bound functional ligands and therefore the effective surface
Shiv Kumar, Tao Chuanjuan, Chien Minchen, Hellner Brittney, Joseph W. Robertson, Arvind Balijepalli, Li Zengmin, James J. Russo, Joseph E. Reiner, John J. Kasianowicz, Jingyue Ju
There is a significant need to accurately sequence single DNA and RNA molecules for personalized medicine. We describe a novel nanopore-based sequencing by synthesis (SBS) strategy that will accurately differentiate at single molecule level four different
Justin M. Zook, Melissa D. Halter, Danielle Cleveland, Stephen E. Long
Silver nanoparticles (AgNPs) are frequently coated by a variety of polymers, which may affect various intertwined mechanisms of toxicity, including agglomeration and dissolution rate. Here, we measure how citrate, dextran, poly(ethylene glycol) (PEG)
Germarie Sanchez-Pomales, Todd A. Morris, James Falabella, Michael J. Tarlov, Rebecca A. Zangmeister
We report a glycoanalysis method in which lectins are used to probe the glycans of glycoproteins that are adsorbed on gold nanoparticles. A model mannose-presenting glycoprotein, ribonuclease B (RNase B), and the therapeutic monoclonal antibody (mAb)
De-Hao D. Tsai, Sherrie R. Elzey, Frank W. DelRio, Robert I. MacCuspie, Suvajyoti S. Guha, Michael R. Zachariah, Athena M. Keene, Jeffrey D. Clogston, Vincent A. Hackley
We report on a systematic investigation of molecular conjugation of tumor necrosis factor protein-α (TNF) onto gold nanoparticles (AuNPs) and the subsequent binding behavior to its antibody (anti-TNF). We employ a combination of physical and spectroscopic
Through-focus scanning optical microscopy (TSOM) method provides three-dimensional information (i.e. the size, shape and location) about micro- and nanometer-scale structures. TSOM, based on a conventional optical microscope, achieves this by acquiring and
We present an initial review of a novel through-focus scanning optical microscopy (TSOM) imaging method that produces nanometer dimensional measurement sensitivity using a conventional bright-field optical microscope. In the TSOM method a target is scanned
Through-focus scanning optical microscopy (TSOM) is a relatively new method that transforms conventional optical microscopes into truly three-dimensional metrology tools for nanoscale to microscale dimensional analysis. TSOM achieves this by acquiring and
Anmiv Prahbu, Kevin J. Freedman, Joseph W. Robertson, Zhorro Nikolov, John J. Kasianowicz, MinJun Kim
We have investigated the shrinkage of solid state nanopores by a scanning electron microscope and find the process to be reproducible and dependant beam parameters such as the accelerating voltage and electron flux. The shrinking phenomenon does not
Joseph T. Hodges, David A. Long, Daniel K. Havey, S. S. Yu, M Okumura, Charles E. Miller
Frequency-stabilized cavity ring-down spectroscopy (FS-CRDS) was employed to measure over 100 transitions in the R-branch of the b1Σg+←X3Σg-(0,0) band for the rare O2 isotopologues. The use of 17O- and 18O-enriched mixtures allowed for line positions to be
De-Hao D. Tsai, Melissa Davila-Morris, Frank W. DelRio, Suvajyoti S. Guha, Vincent A. Hackley, Michael R. Zachariah
Surface-sensitive quantitative studies of competitive molecular adsorption on nanoparticles were conducted using a modified Attenuated attenuated Total total Reflectionreflectance-Fourier Transform transform Infrared infrared (ATR-FTIR) spectroscopy method
Joseph T. Hodges, A. Cygan, Piotr Maslowski, Katarzyna E. Bielska, S. Wojtewicz, J. Domyslawska, Hisashi Abe, R.S. Trawinski, R. Ciurylo
We describe a high sensitivity and high spectral resolution laser absorption spectrometer based upon the frequency-stabilized cavity ring-down spectroscopy (FS-CRDS) technique. We used the Pound-Drever-Hall (PDH) method to lock the probe laser to the high
By transferring of a small part of a macroscale sample to a novel thermally insulated sample platform we are able to mitigate flooding and electron heating problems typically associated with Environmental Scanning Electron Microscopy imaging of water
Silvia H. De Paoli Lacerda, Jana Semberova, Karel Holada, Olga Simakova, Steven D. Hudson, Jan Simak
Intravascular effects of carbon nanotubes (CNTs) as a result of their various biomedical applications or environmental/occupational exposure raise serious safety concerns. CNTs potentiate arterial thrombosis in animal models;[1, 2] however, a mechanism of
Ravikiran Attota, Ronald G. Dixson, John A. Kramar, James E. Potzick, Andras Vladar, Benjamin D. Bunday, Erik Novak, Andrew C. Rudack
Through-focus scanning optical microscopy (TSOM) is a new metrology method that achieves 3D nanoscale measurement resolution using conventional optical microscopes; measurement sensitivities are comparable to what is typical using Scatterometry, SEM and
Mingdong M. Li, Suvajyoti S. Guha, Rebecca A. Zangmeister, Michael J. Tarlov, Michael R. Zachariah
Electrospray (ES) sources are commonly used to introduce non-volatile materials (e.g. nanoparticles, proteins, etc.) in to the gas phase for characterization by mass spectrometry and ion mobility. Recent studies in our group using electrospray ion mobility
Kavita M. Jeerage, Stephanie M. LaNasa, Holly A. Hughes, Damian S. Lauria, Stephanie J. Bryant, Andrew J. Slifka
Scanning electrochemical microscopy has been used to examine the molecular transport properties of photopolymerized poly(ethylene glycol) (PEG) hydrogels having different mesh sizes. Both the molecular weight (508 Da or 3000 Da) of the PEG diacrylate
Asymmetrical-flow field flow fractionation (AFFF) separates constituents based on hydrodynamic size, and is emerging as a powerful tool for obtaining high-resolution information on the size, molecular weight, composition, and stability of nanoscale
Gary Zabow, John M. Moreland, Stephen Dodd, alan koretsky, erik shapiro
While chemically synthesized superparamagnetic microparticles have enabled much new research based on MRI tracking of magnetically labeled cells, signal-to-noise levels still limit the potential range of applications. Here it is shown how, through top-down
Joseph E. Reiner, John J. Kasianowicz, Joseph W. Robertson
Polyethylene glycol (PEG) is a ubiquitous charge-neutral polymer having several useful properties. It has been used to estimate the diameter of functioning nanopores. In this talk I will describe how the detailed analysis of PEG induced current blockades
Ravikiran Attota, Richard J. Kasica, Lei Chen, Premsagar P. Kavuri, Richard M. Silver, Andras Vladar
We present a novel optical TSOM (through-focus scanning optical microscopy - pronounced as 'tee-som') method that produces nanoscale dimensional measurement sensitivity using a conventional optical microscope. The TSOM method uses optical information from
Joseph E. Reiner, John J. Kasianowicz, Brian J. Nablo, Joseph W. Robertson
Nanometer-scale pores have demonstrated potential as a tool for the electrical detection and characterization of molecules. To provide a physical basis for nanopore-based analytical metrology, we show that a simple model quantitatively describes how one