Use of grease or wax in the polymerase chain reaction
First Claim
1. A PCR reaction tube comprising a container, an aqueous mixture of PCR reagents, said mixture having contact with the atmosphere, and an amount of grease or wax sufficient in mass to separate completely the aqueous mixture from the atmosphere above it, when said grease or wax is liquified.
1 Assignment
0 Petitions
Accused Products
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.
236 Citations
27 Claims
- 1. A PCR reaction tube comprising a container, an aqueous mixture of PCR reagents, said mixture having contact with the atmosphere, and an amount of grease or wax sufficient in mass to separate completely the aqueous mixture from the atmosphere above it, when said grease or wax is liquified.
- 16. A composition comprising a plastic container containing an aqueous mixture of PCR reagents for amplifying nucleic acid using repeated heating and cooling cycles, said mixture having contact with the atmosphere, wherein the inner surface of said container is hydrophilic and wherein said mixture contains a grease or wax sufficient in mass to separate completely the mixture from any atmosphere above it when said grease or wax is liquified.
-
18. A kit comprising one or more containers containing an aqueous mixture of PCR reagents comprising at least two reagents suitable for conducting PCR said mixture having an exposed surface in contact with the atmosphere and a mass of grease or wax sufficient to cover the exposed surface of PCR reactions when said grease or wax is liquified.
-
19. A method for sealing a PCR reaction tube containing between about 20 μ
- l and 200 μ
l of an aqueous solution, wherein the volume of said tube is less than about 600 μ
l, comprising;(a) adding between 5 mg and 30 mg of a wax that comprises a non-ionic surfactant dissolved in said wax to a concentration between about 0.1% and about 1% by weight and that melts in the range of about 40°
C. to about 90°
C. to said aqueous solution,(b) heating said wax to a temperature higher than the melting point of said wax and maintaining said temperature until said wax forms a liquid layer on top of said aqueous solution, and (c) cooling said liquid layer to form a solid layer completely covering said aqueous solution. - View Dependent Claims (20, 21, 22)
- l and 200 μ
-
23. A method for producing a vapor barrier over an aqueous mixture of PCR reagents in a tube, said mixture having an upper surface exposed to the atmosphere and said method comprising the steps of:
-
(a) adding an amount of wax to the aqueous mixture sufficient when liquified to form a vapor barrier on the upper surface of the mixture; (b) heating the aqueous mixture to initiate the amplification reaction said heat sufficient to liquify the wax; and (c) permitting the liquified wax to flow upon the upper surface of the mixture forming a vapor barrier. - View Dependent Claims (24, 25, 26, 27)
-
Specification