Patent ID: 8257926

Claim:
A method of detecting nucleic acid hybridization, wherein the method comprises the steps of: a) labeling a nucleic acid with a dye of the following structure to form a dye-nucleic acid conjugate: wherein C is a non-conjugated chain of 10 to 50 linear atoms selected from a group consisting of carbon and nitrogen that are further substituted by substituents selected from a group consisting of hydrogen, alkyl having 1-20 carbons, hydroxyl, carbonyl, and RGM; n is 0, 1, 2 or 3; R 1 , R 2 and R 3 are independently a hydrogen having 1-20 carbons, a cycloalkyl having 3-20 carbons, an aryl, a heteroaryl, an amino, an alkylamino, an arylamino, a thiol, an alkylthio or a RGM; R 4 -R 11 and R 13 -R 16 are independently a hydrogen, an alkyl having 1-20 carbons, a hydroxyl, an alkoxy having 1-20 carbons, a fluorinated alkyl, a halogen, an alkylthiol, a sulfonyl, a carbonyl, a hydroxyl, an amino, an alkylthio, a sulfate, a phosphonate or a RGM; RGM is a carboxylic acid, an activated ester of a carboxylic acid, an acyl azide, an acyl nitrile, an imido ester, an isocyanate, or a maleimide; b) hybridizing the dye-nucleic acid conjugate to a cellular preparation; and, c) determining long-wavelength fluorescence of labeled cells by excitation through an optical filter; thereby detecting nucleic acid hybridization.