Charge-switch nucleotides

A charge-switch nucleotide phosphate (NP) probe, said NP probe comprising:

• an intact NP probe having a terminal phosphate with a fluorophore moiety attached thereto via a linker carrying at least two positive charges, wherein said terminal phosphate is a pyrophosphate with a fluorophore moiety attached thereto, said intact NP probe having a first molecular charge associated therewith, whereupon cleavage of said terminal phosphate as a phosphate fluorophore moiety, said phosphate fluorophore moiety carries a second molecular charge, wherein the difference between said first molecular charge and said second molecular charge is at least 0.5.

A charge-switch nucleotide phosphate (NP) probe, said NP probe comprising:

• an intact NP probe having a terminal phosphate with a fluorophore moiety attached thereto, said intact NP probe having a first molecular charge associated therewith, whereupon cleavage of said terminal phosphate as a phosphate fluorophore moiety, said phosphate fluorophore moiety carries a second molecular charge, wherein the difference between said first molecular charge and said second molecular charge is at least 0.5, wherein said charge-switch probe is selected from the group consisting of compound 50, 51, 52, 53, 54, 55, 56, 57, 58, 59 and 60 in FIGS. 6A-D.

An intact charge-switch nucleotide phosphate (NP) probe, wherein upon enzymatic cleavage of said intact charge-switch NP probe to produce a phosphate detectable moiety, said phosphate detectable moiety migrates to an electrode, and said intact charge-switch NP probe migrates to the other electrode, wherein said charge-switch NP probe is a nucleotide triphosphate (NTP) and said phosphate detectable moiety is a pyrophosphate with a fluorophore moiety attached thereto.

An intact charge-switch nucleotide phosphate (NP) probe, wherein upon enzymatic cleavage of said intact charge-switch NP probe to produce a phosphate detectable moiety, said phosphate detectable moiety migrates to an electrode, and said intact charge-switch NP probe migrates to the other electrode, and wherein said charge-switch NP probe is a member selected from the group consisting of a deoxynucleotide triphosphate (dNTP), and a nucleotide triphosphate (NTP).

An intact charge-switch nucleotide phosphate (NP) probe, wherein upon enzymatic cleavage of said intact charge-switch NP probe to produce a phosphate detectable moiety, said phosphate detectable moiety migrates to an electrode, and said intact charge-switch NP probe migrates to the other electrode, wherein at least one of the phosphate moieties of said nucleotide phosphate probe has an ionized oxygen atom with a counter-cation associated therewith.