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Notice of Government Owned Inventions Available for Licensing

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National Institute of Standards and Technology, Commerce.


Notice of government owned invention available for licensing.


The invention listed below is owned in whole by the U.S. Government, as represented by the Department of Commerce. The invention is available for licensing in accordance with 35 U.S.C. 207 and 37 CFR part 404 to achieve expeditious commercialization of results of federally funded research and development.

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Technical and licensing information on this invention may be obtained by writing to: National Institute of Standards and Technology, Office of Technology Partnerships, ATTN: Mary Clague; Building 820, Room 213, Gaithersburg, MD 20899. Information is also available via telephone: 301-975-4188, e-mail:; or fax: 301-869-2751. Any request for information should include the NIST Docket number and title for the invention as indicated below.

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NIST may enter into a Cooperative Research and Start Printed Page 70719Development Agreement (“CRADA”) with the licensee to perform further research on the invention for purposes of commercialization. The invention available for licensing is:

NIST Docket Number: [01-029US].

Title: Simplified Method For Electrokinetic Focusing Of Samples In Microfluidic Devices.

Abstract: 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 the possibilty that any apparatus/system which can be used for electrokinetic focusing can also be used to produce streams of either concentrated or diluted analytes.

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Dated: November 18, 2002.

Karen H. Brown,

Deputy Director.

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[FR Doc. 02-29935 Filed 11-25-02; 8:45 am]