Charge-tagged nucleotides and methods of use thereof

A method comprising:

• detecting an incorporation of a labelled nucleotide into a nascent polynucleotide strand complementary to a template polynucleotide strand by a polymerase, wherein the polymerase is tethered to a solid support conductive channel by a tether,
• the labelled nucleotide is a compound of Formula I
• wherein n is an integer from 3 to 10,
• m is an integer from 1 to 10,
• t is an integer from 0 to 50,
• X1 is a direct bond, a C1-C10 alkyl, a C1-C10 oxaalkyl, a C1-C10 thiaalkyl, or a C1-C10 azaalkyl,
• X2 is C1-C20 alkyl wherein optionally one or more individual CH2 residue is replaced with one or more of a peptide bond and (—O—CH2—CH2—)a wherein a is an integer from 1 to 24,
• X3 is a an oligonucleotide wherein the oligonucleotide hybridizes to an acceptor region of the tether,
• F1 is selected from a fluorophore and a direct bond and F2 is absent or a fluorophore,
• A was formed by a reaction comprising a linking reaction and the linking reaction is selecting from an azide-alkyne copper-assisted click reaction, a tetrazine-trans-cyclooctene ligation, an azide-dibenzocyclooctyne group copper-free click reaction, a thiol-maleimide conjugation, and a N-hydroxysuccinimide ester-amine linkage reaction, and
• Y is selected from
• q is an integer from 1 to 100, and
• B is selected from (i) an amino acid;
• (ii) a nucleotide;
• wherein each R is independently selected from Y and hydrogen;
• and (v) a dendron;
• and
• wherein q is equal to 1 when B is a dendron, and
• the conductive channel is to detect the labelled nucleotide during the incorporation.