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Search Publications by: Samuel M. Stavis (Fed)

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Displaying 26 - 50 of 60

Dimensional Reduction of Duplex DNA Under Nanofluidic Slit Confinement

August 19, 2015
Author(s)
Luis Fernando Vargas Lara, Jack F. Douglas, Samuel M. Stavis, Elizabeth A. Strychalski, Jon C. Geist, Brian J. Nablo
There has been much recent interest in the dimensional properties of duplex DNA under nanoscale confinement conditions as a problem of fundamental interest in both technological and biological fields. This has led to a series of measurements by

Characterization of Electrothermal Actuation with Nanometer and Microradian Precision

June 21, 2015
Author(s)
Craig R. Copeland, Craig D. McGray, Jon C. Geist, Vladimir A. Aksyuk, Samuel M. Stavis
A recently introduced particle-tracking method was used to measure the single motion cycles of an electrothermal actuator with nanometer and microradian precision. Driving the actuator with a low-noise input induced deterministic motion that was perfectly

Kilohertz Rotation of Nanorods Propelled by Ultrasound, Traced by Microvortex Advection of Nanoparticles

August 26, 2014
Author(s)
Andrew L. Balk, Lamar O. Mair, Pramod Mathai, Paul N. Patrone, Wei Wang, Suzanne Ahmed, Thomas Mallouk, James A. Liddle, Samuel M. Stavis
We measure the microvortical flows around gold nanorods propelled by ultrasound in water using polystyrene nanoparticles as optical tracers. We infer the rotational frequencies of such nanomotors assuming a hydrodynamic model of this interaction. In this

High-speed, high-purity separation of gold nanoparticle-DNA origami constructs using centrifugation

July 23, 2014
Author(s)
Seung H. Ko, Luis F. Vargas Lara, Paul Patrone, Samuel Stavis, Francis W. Starr, Jack F. Douglas, James Alexander Liddle
DNA origami is a powerful platform for assembling gold nanoparticle constructs, an important class of nanostructure with numerous applications. Such constructs are assembled by the association of complementary DNA oligomers. These association reactions

MEMS Kinematics by Super-Resolution Fluorescence Microscopy

September 27, 2012
Author(s)
Craig D. McGray, Samuel M. Stavis, Joshua Giltinan, Eric Eastman, Samara L. Firebaugh, Jenelle Piepmeier, Jon C. Geist, Michael Gaitan
Super-resolution fluorescence microscopy is used for the first time to study the nanoscale kinematics of a MEMS device in motion across a surface. A device under test is labeled with fluorescent nanoparticles that form a microscale constellation of near

A Glowing Future for Lab on a Chip Testing Standards

June 28, 2012
Author(s)
Samuel M. Stavis
Testing standards are more fundamental from a metrological perspective and less controversial from an industrial perspective than product standards, representing a path of less resistance towards the standardization and commercialization of lab on a chip

DNA Molecules Descending a Nanofluidic Staircase by Entropophoresis

January 26, 2012
Author(s)
Samuel M. Stavis, Jon C. Geist, Michael Gaitan, Laurie E. Locascio, Elizabeth A. Strychalski
A complex entropy gradient for confined DNA molecules was engineered for the first time. Following the second law of thermodynamics, this enabled the directed self-transport and self-concentration of DNA molecules. This new nanofluidic method is termed

DNA ENTROPOPHORESIS: A BALANCE OF ENTROPY AND DIFFUSION IN COMPLEX NANOCONFINEMENT

October 3, 2011
Author(s)
Samuel Stavis, Jon Geist, Michael Gaitan, Laurie E. Locascio, Elizabeth Strychalski
Entropophoresis - motion caused by an entropy gradient - is a novel nanofluidic method to direct the self-transport of biopolymers that established a new paradigm of nanofluidic functionality with broad relevance to lab-on-a-chip technol-ogy. Here, the

Nanoslinky: DNA Entropophoresis Down a Nanofluidic Staircase

October 4, 2010
Author(s)
Elizabeth A. Strychalski, Laurie E. Locascio, Samuel M. Stavis, Michael Gaitan
Almost all nanofluidic devices for biopolymer analysis have been limited by one or two confining structural dimen-sions or the application of external forces for biopolymer manipulation, which has restricted the scope of related lab-on-a-chip technology

Separation and Metrology of Nanoparticles by Nanofluidic Size Exclusion

August 11, 2010
Author(s)
Samuel M. Stavis, Jon C. Geist, Michael Gaitan
A nanofluidic approach to the separation and metrology of nanoparticles is demonstrated. Advantages of this approach include nanometer-scale resolution, nanometer-scale to submicrometer-scale range, mitigation of hydrodynamic and diffusional limitations to