SPECIAL NOTICE
A -- Special Notice
- Notice Date
- 5/17/2002
- Notice Type
- Special Notice
- Contracting Office
- Department of Commerce, National Institute of Standards and Technology (NIST), Acquisition and Logistics Division, 100 Bureau Drive, Building 301, Room B129, Mail Stop 3571, Gaithersburg, MD, 20899-3571
- ZIP Code
- 20899-3571
- Archive Date
- 6/30/2002
- Description
- NIST DOCKET NUMBER: 01-029PA2 Title: Simplified Methods for Electrokinetic Focusing of Samples in Microfluidic Devices Description: Methods are described for the focusing of ionic species in microfluidic systems using electric field gradients that are generated without external electrical connections. In the first example, the electric field within a microchannel is effected by putting a highly or partially conductive material inside portions of the channel. The conductive material can consist, for example, of a metal film on the channel walls. The presence of conductive material will alter the total conductivity of the microchannel, and thereby alter the electric field in the microchannel. Regions of different electric field can be created by applying different films (or no films)to different regions of the microchannel. The electric field gradients at the borders between these different regions can then be used to focus and concentrate ionic species by balancing their electrophoretic velocities with an applied bulk fluid velocity. In the second example, the electric field gradient which is used for electrokinetic focusing is created by application of a temperature gradient. In order for this to work, the conductivity of the buffer within the microchannels must depend on temperature in a way that differs from the typical inverse proportionality with the buffer viscosity. For example, it must have an ionic strength that is temperature dependent. Also discussed is a related method which can be used to produce streams of either concentrated or diluted analytes. For further information, call Mary Clague (301)975-4188.
- Web Link
-
Link to FedBizOpps document.
(http://www.eps.gov/spg/DOC/NIST/AcAsD/Reference-Number-01-029PA2/listing.html)
- Record
- SN00079495-F 20020519/020517214411 (fbodaily.com)
- Source
-
FedBizOpps.gov Link to This Notice
(may not be valid after Archive Date)
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