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Search Publications by: Wyatt N. Vreeland (Fed)

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Displaying 1 - 25 of 45

Size and Number Concentration Measurements of Polystyrene Nanoparticle Suspensions using Several Different Techniques

September 8, 2022
Paul C. DeRose, Kurt D. Benkstein, Elzafir B. Elsheikh, Adolfas K. Gaigalas, Sean Lehman, Dean C. Ripple, Linhua Tian, Wyatt N. Vreeland, Adam York, Yu-Zhong Zhang, Lili Wang
The number concentrations of nominal 100 nm, 200 nm and 500 nm diameter, fluorescently-labeled polystyrene nanosphere suspensions were measured using seven different techniques. Diameter values were also measured where possible. The diameter values were

Distribution of Average Aggregate Density from Stir-stressed NISTmAb Protein

March 19, 2022
Richard E. Cavicchi, Laura Philips, Fook Cheong, David Ruffner, Priya Kasimbeg, Wyatt N. Vreeland
Quantifying the heterogeneous nature of protein aggregates is important to understanding the impact aggregates may have on the performance of antibody therapeutics. The spatially averaged density p of aggregates, defined as the total mass, including water

Characterization of extracellular vesicles and artificial nanoparticles with four orthogonal single-particle analysis platforms

April 6, 2021
Emily Mallick, Tanina Arab, Yiyao Huang, Liang Dong, Zhaohao Liao, Zezhou Zhao, Barbara Smith, Norman J. Haughey, Kenneth Pienta, Barbara Slusher, Patrick Tarwater, Juan Pablo Tosar, Angela M. Zivkovic, Wyatt N. Vreeland, Michael E. Paulaitis, Kenneth W. Witwer
We compared four orthogonal technologies for sizing, counting, and phenotyping of extracellular vesicles (EVs) and synthetic particles. The platforms were: single-particle interferometric reflectance imaging sensing (SP-IRIS) with fluorescence

Measurement and Standardization Challenges for Exosome-Based Delivery Vectors

September 4, 2020
Bryant C. Nelson, Lili Wang, Samantha D. Maragh, Paul C. DeRose, Elzafir B. Elsheikh, Wyatt N. Vreeland, Ionita Ghiran, Jennifer Jones
Extracellular vesicles (EVs), and in particular exosomes, have the potential to revolutionize the development and efficient delivery of clinical therapeutics. In this Perspective, we focus on providing a brief introduction to the landscape of exosome-based

Microfluidic Remote Loading for Rapid Single-Step Liposomal Drug Preparation

July 29, 2014
Wyatt N. Vreeland, Renee R. Hood, Don L. DeVoe
Here we report a microfluidic system that enables rapid and efficient remote loading of amphipathic drugs into nanoscale liposomes, combining liposome synthesis and remote drug loading in a continuous integrated process. Unlike established bulk methods for

A Facile Route to the Synthesis of Monodisperse Nanoscale Liposomes Using 3D Microfluidic Hydrodynamic Focusing in a Concentric Capillary Array

May 14, 2014
Wyatt N. Vreeland, Renee R. Hood, Don L. DeVoe, Francisco J. Atencia, Donna M. Omiatek
A novel microscale device has been developed to enable the one-step continuous flow assembly of monodisperse nanoscale liposomes using three-dimensional microfluidic hydrodynamic focusing (3D-MHF) in a radially symmetric capillary array. The 3D-MHF flow

Microfluidic-Enabled of Liposomes Elucidate Size-Dependent Transdermal Transport

March 21, 2014
Wyatt N. Vreeland, Renee R. Hood, Eric Kendall, Don L. DeVoe, Julia Finkel, Mariana Junqueira, Zenaide Quezado
Microfluidic synthesis of small and nearly-monodisperse liposomes is used to investigate the size-dependent passive transdermal transport of nanoscale lipid vesicles. While large liposomes with diameters above 105 nm are found to be excluded from deeper

Microfluidic Synthesis of Nano-Liposomal Anesthetics

May 12, 2013
Wyatt N. Vreeland, Renee R. Hood, Eric Kendall, Mariana Junqueira, Julia Finkel, Don L. DeVoe
Topical anesthesia has the ability to provide painless application of pain management medications for minor procedures such as venipuncture, particularly in the pediatric population. Liposomes have been proposed as a highly advantageous nanocarrier for

Radiation-Induced Synthesis of Poly(vinylpyrrolidone) Nanogel

October 14, 2011
Jung-Chul An, Alia Weaver, Byungnam Kim, Aaron Barkatt, Dianne L. Poster, Wyatt N. Vreeland, Joseph Silverman, Mohamad Al-Sheikhly
Studies of the radiation-induced synthesis of poly(vinylpyrrolidone) (PVP) nanogels, intended to provide a basis for obtaining intra-molecular cross-linked products, which are more useful in drug delivery, show that a sharp change in the controlling

A rapid, low-cost preparation of monodisperse niosomes in a microfluidic platform

June 1, 2010
Catherine T. Lo, Andreas Jahn, Wyatt N. Vreeland, Laurie E. Locascio
Niosomes are synthetic membrane vesicles made of self-assembled non-ionic surfactants (i.e. amphiphilic organic compounds). They bear the same properties as liposomes, namely having an aqueous interior that is separated from the exterior aqueous

Microfluidic Mixing and the Formation of Nanoscale Lipid Vesicles

April 27, 2010
Andreas Jahn, Samuel M. Stavis, Jennifer S. Hong, Wyatt N. Vreeland, Don L. DeVoe, Michael Gaitan
We investigate the formation of unilamellar lipid vesicles (liposomes) with diameters of tens of nanometers by microfluidic hydrodynamic focusing (MHF). Our study includes liposome synthesis experiments and numerical modeling of our microfluidic

Accurate optical analysis of single molecule entrapment in nanoscale vesicles

January 1, 2010
Joseph E. Reiner, Andreas Jahn, Samuel M. Stavis, Michael J. Culbertson, Wyatt N. Vreeland, Daniel L. Burden, Jon C. Geist, Michael Gaitan
We present a non-destructive method to characterize low analyte concentrations in nanometer scale lipid vesicle formulations. Our method is based on the application of fluorescence fluctuation analysis (FFA) and multi-angle laser light scattering (MALLS)

Magnetic connectors for microfluidic applications

January 1, 2010
Francisco J. Atencia, Gregory A. Cooksey, Andreas Jahn, Justin M. Zook, Wyatt N. Vreeland, Laurie E. Locascio
We present a new type of connector based on a simple idea: using a ring magnet on one side of the microfluidic chip and a disc magnet on the other side to provide the interfacial force necessary to provide a sealed connection between tubing or needles and

Contactless Differential Conductivity Detection

October 12, 2008
Gordon A. Shaw, David J. Ross, Steven E. Fick, Wyatt N. Vreeland
We propose a new technique, contactless differential conductivity detection (CDCD,) to improve the detection limit of contactless conductivity detection for capillary and microchannel electrophoresis. By exploiting a 3-electrode differential configuration

Microfluidic DNA Analysis Systems for Forensic Applications

July 18, 2008
Michael Gaitan, Jayna J. Shah, Darwin Reyes-Hernandez, Pierre-Alain Auroux, Jon Geist, Laurie E. Locascio, Wyatt N. Vreeland, David J. Ross, Peter Vallone, Paul Smith, Nicole Morgan, Tom Pohida, John Kakareka, Annelise Barron
This report summarizes the NIST effort on microfluidic DNA analysis systems for forensic applications sponsored by the National Institute of Justice. Currently emerging microfluidics-based forensic systems are implemented in silica (glass) because the