Abstract: Improvements to the polymerase chain reaction (PCR), a process for in vitro enzymatic amplification of specific nucleic acid sequences, can be achieved by changing the way that PCR reagents are mixed and the enzymatic reaction is started and by the replacement of mineral oil, commonly used as a vapor barrier to minimize solvent evaporation, by a grease or wax. The use of such mixtures allows for the delay of reagent mixing until the first heating step of a PCR amplification, thereby reducing the enzymatic generation of nonspecific products which occurs when a complete mixture of PCR reagents, with or without test sample, stands at room temperature or below. These mixtures increase the shelf-life of PCR reagents and increase protection of the laboratory environment against contamination by PCR product.
Type:
Grant
Filed:
May 27, 1992
Date of Patent:
May 2, 1995
Assignee:
Hoffmann-La Roche Inc.
Inventors:
Will Bloch, Jonathan Raymond, Alan R. Read
Abstract: An oriented photopolymer is a polymer where photomodification is initiated by irradiation with plane-polarized light and where the molecular configuration has a preferred orientation as a result of linear polarization. These polymers have optically anisotropic and other novel properties.
Type:
Grant
Filed:
September 21, 1993
Date of Patent:
February 14, 1995
Assignees:
Hoffmann-La Roche Inc., Niopic Moscow Research and Production Association
Inventors:
Vladimir G. Chigrinov, Vladimir M. Kozenkov, Nicolic V. Novoseletsky, Victor Y. Reshetnyak, Yuriy A. Reznikov, Martin Schadt, Klaus Schmitt