Patent ID: 7223540

Claim:
A method of detecting an analyte through the occurrence of a polymerase mediated template dependent complementary primer extension reaction in a conducting medium, said method comprising: (a) providing a system comprising an immobilized template nucleic acid and a sample; (b) forming a template primer duplex nucleic acid made up of template and any complementary primer nucleic acids in the analyte in said sample in contact with said medium, wherein said medium comprises a polymerase and a plurality of nucleotides added to a second electrode in said medium; (c) detecting a transient electrical signal indicative of whether or not a primer extension reaction occurs in the medium and produced in said medium by movement of charged nucleotides through the medium towards the immobilized template primer duplex and resultant covalent bonding of said at least one nucleotide to a terminus of said primer nucleic acid; and (d) relating said detected transient electrical signal to the occurrence of a polymerase mediated template dependent primer extension reaction in said medium, said transient electrical signal being a signal dependent on complementary primer nucleic acids in the analyte.