Patent ID: 6251591
Filing Date: 2001-06-26
Classification: C12Q

Abstract:
A method for determining a concentration of at least one single stranded or double stranded nucleobase-containing target sequence in a fluid medium, said method comprising:adding to said fluid medium antisense probes capable of forming hybridization complexes with said at least one nucleobase-containing target sequence, wherein said antisense probes comprise fluorescent markers and backbones having a charge that is less negative than a comparable phosphodiester backbone;separating unhybridized antisense probes from said hybridization complexes to form a test medium;irradiating said test medium with a laser beam having a wavelength which excites fluorescent markers in said hybridization complexes and causes said fluorescent markers to emit fluorescent light;measuring an intensity of said emitted fluorescent light; andcomparing said measured intensity with a reference intensity to determine a concentration of said at least one target sequence in said fluid medium,wherein said measured intensity is proportional to said concentration, and wherein said method other than said separating step is entirely conducted without binding said antisense probes, said at least one nucleobase-containing target sequence or said hybridization complexes to a solid support or gel.