A method for the formation of double stranded nucleic acid molecules from separate single stranded nucleic acid molecules in a single phase reaction solution is disclosed wherein the rate of reaction is greatly increased over the rate of reaction at standard reference conditions. The greatly accelerated reaction rate is accomplished through the use of known concentrations of nucleic acid precipitating agents which are added to the reaction solution. Nucleic acid denaturing agents may also be added. The solution so formed is incubated and then assayed for the presence of double stranded nucleic acid molecules.

A solid support capable of binding a nucleic acid thereto upon suitable irradiation, comprising (a) a solid substrate, (b) a member selected from the group consisting of a furocoumarin, a phenanthridium halide, and photochemically reactive derivatives thereof, and (c) a divalent radical chemically linking the substrate and the member (b). Specifically, a hydroxy group-containing solid substrate such as nitrocellulose paper is linked via a bifunctional reagent such as cyanogen bromide or 1,4-butanediol diglycidyl ether to an amino-substituted angelicin or psoralen or phenanthridinium bromide which in turn is photochemically linked to a nucleic acid. This is capable of hybridizing with other nucleic acid fragments and is thereby useful in diagnostic assays.

Novel photolabile photochemical reagents are disclosed. The reagents are useful in a variety of biochemical and chemical contexts, including nucleic hybridization assays and chemical phosphorylation of hydroxyl-containing compounds. The reagents are particularly useful for introducing cleavable sites into oligonucleotide or polynucleotide chains, i.e., sites which are cleavable upon photolysis. The reagents are also useful in both 5'- and 3'-phosphorylation of oligonucleotide or polynucleotide chains.

DNA sequences of hCMV are obtained by restriction of the hCMV genome, the resulting fragments free of fragments cross-hybridizing with human DNA and other viruses may be used for hybridization with clinical samples suspected of containing hCMV to provide a sensitive method for detection of hCMV at low particle number.

Message RNA is immobilized directly from cells onto filter material. Immobilization is carried out by solubilizing cellular components with a chaotropic salt, passing the resultant solubilized cellular components through a filter which selectively binds message RNA and baking the filter containing bound message RNA. The chaotropic salt is preferably sodium iodide, potassium iodide or sodium perchlorate. Prior to solubilizing, the cells may be washed and lysed. The bound message RNA can be hybridized to a labeled probe and the amount of message RNA measured. Prior to baking, the filter containing bound RNA may be incubated in a solution which acelylates basic protein and other molecules which might interfere with molecular hybridization.