U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by: Vytas Reipa (Fed)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 26 - 50 of 68

Physicochemical characterization and in vitro hemolysis evaluation of silver nanoparticles

June 7, 2011
Author(s)
Vytautas Reipa, Jonghoon Choi, Nam S. Wang, Victoria M. Hitchins, Peter L. Goering, Robert Malinauskas
In anticipation of the increased use of various forms of silver as an antimicrobial agent in medical devices, the objective of this study was to evaluate the in vitro hemolytic potential of silver nanoparticles in dilute human blood, and to relate particle

Nanomaterial Toxicity: Emerging Standards and Efforts to Support Standards Development

February 1, 2011
Author(s)
Laurie E. Locascio, Vytautas Reipa, Justin M. Zook, Richard C. Pleus
For the first time in the history of industrialization, nanotechnology offers the unique opportunity to consider material safety ahead of its full implementation. Many scientists around the world have been motivated by this and are working on developing

Measurement of Nanoparticle Concentration Using Quartz Crystal Microgravimetry

December 16, 2010
Author(s)
Vytautas Reipa, Geoffrey Purdum, Jonghoon Choi
A common issue, encountered in nanoparticle-biological system interaction studies is accurate nanoparticle concentration expression, given the critical importance of the dose-response relationships. We present here the application of quartz crystal

Porous Silicon Biosensor for MS2 Virus

November 19, 2007
Author(s)
Andrea Rossi, Lili Wang, Vytas Reipa, Thomas E. Murphy
Nanoporous silicon was discovered in the 1950 s and has unique properties due to quantum confinement effects. It is produced by electrochemical etching in HF containing electrolytes that allows to tune the pore diameter from a few nanometers up to several

Covalent Attachment of Photoluminescent Silicon Nanoparticles to Streptavidin

September 11, 2007
Author(s)
Jonghoon Choi, Peter Niarhos, Nam S. Wang, Vytas Reipa
We have covalently attached multiple fluorescent silicon nanocrystals (SNs) to streptavidin molecule. Selective conjugation of SNs to a target protein is accomplished using sequential silicon surface termination chemistry. In the first step, freshly

Photo-Assisted Tuning of Si Nano-Crystal Photoluminescence

February 2, 2007
Author(s)
Jonghoon Choi, Nam S. Wang, Vytas Reipa
Silicon is rather inefficient light emitter due to the indirect-band gap electronic structure, requiring a phonon to balance electron momentum during interband transition. Fortunately, momentum requirements are relaxed in 1-5 nm dia Si crystals as a result

Infrared and Raman Spectroscopy Characterization of Biological Products

January 1, 2005
Author(s)
Vytautas Reipa
Both infrared and Raman are increasingly applied in biomolecular structure characterization, thus getting acceptance alongside traditional bioanalytical techniques. Physical principles and biological sampling requirements are reviewed. Advanced

Direct Spectroelectrochemical Titration of Glutathione

December 1, 2004
Author(s)
Vytautas Reipa
Spectroelectrochemistry measurements are used to determine the formal potential E of glutathione. Nernst titration was performed by monitoring disulfide absorption at 258 nm in a thin layer cell. Use of nanocrystalline highly doped tin oxide electrodes

Electrochemical Properties of Nanocrystalline Cadmium Stannate Films

August 1, 2001
Author(s)
Gintaras Valincius, Vytas Reipa, V L. Vilker, John T. Woodward IV, Mark D. Vaudin
Electrochemical properties of the sol-gel nanocrystalline cadmium tin oxide electrodes (CTO) were investigated in 0.2 M potassium chloride buffered at pH 7.4 with phosphate. Films were found to be n-type degenerate semiconductors with charge carrier levels

Temperature Dependence of the Formal Reduction Potential of Putidaredoxin

July 20, 2000
Author(s)
Vytautas Reipa, Marcia J. Holden, M P. Mayhew, V L. Vilker
Putidaredoxin (Pdx), a [2Fe-2S] redox protein of size M r transfers two electrons in two separate steps from the flavin containing putidaredoxin reductase to the heme protein, cytochrome CYP101 in the P450cam catalytic cycle. It has recently come to light