A -- DEVELOPMENTS AT NIST

Researchers at the National Institute of Standards and Technology (NIST) are working on the following technologies. For further information, contact the: National Institute of Standards and Technology, Office of Technology Partnerships, 100 Bureau Drive, Stop 2200, Gaithersburg, Maryland 20899; Fax: 301-869-2751. This is not an announcement of a contract action or a grant. **NIST DOCKET NUMBER: 01-029CIP1 Title: Mixing Reactions by Temperature Gradient Focusing Description: The new use of TGF in this invention involves analyte-ligand interactions that occur as a result of focusing one (the ligand or analyte) and allowing interactions with the second (analyte or ligand) to occur. The mixing interaction can be a hybridization event between nucleic acids such as single stranded DNA/DNA or DNA/peptide nucleic acid (PNA), a chemical reaction, an enzyme/substrate reaction, a protein/protein, or drug/target interaction. In addition, moving the focused product through the temperature gradient after mixing allows additional information to be inferred if the assay displays a temperature dependent interaction (i.e. nucleic acid duplex melting or precipitation of thermoresponsive polymers). **NIST DOCKET NUMBER: 01-029CIP2 Title: Chiral Temperature Gradient Focusing Description: The invention describes a variant of temperature gradient focusing that uses chirally selective additives to modify the electrophoretic mobility of analytes thereby providing a method for focusing and separation of analytes based on their chirality. **NIST DOCKET NUMBER: 04-018 Title: Solid State Radiance Calibration Source Description: With the development of light-emitting diodes (LED) at many different wavelengths, compact, quasi-monochromatic sources can be developed for radiometric uses. Temporally stable, spatially uniform and radiometrically calibrated sources are needed in many different applications. Instead of using large integrating sphere sources, such radiance sources can also be used to measure the size-of-source effect (SSE) in radiation thermometers. These compact sources can be used for both initial characterizations and for periodic measurements to determine that the SSE has not changed. This invention describes the design, construction, and characterization of a unique LED-based radiance source (LRS). Different diffuser materials are assessed for spatial and angular uniformity.