Table 1.

Electron-Transfer Rate Constants of NB–DNA (k_NB–DNA) and MB′–DNA (k_MB′–DNA) as Single-Stranded DNA (ssDNA) and Double-Stranded DNA (dsDNA) under Different Running Conditions

	ssDNAc		dsDNAc (0 mM MgCl2)		dsDNAc (100 mM MgCl2)
	log(kMB′–DNA/s−1)a	log(kNB–DNA/s−1)a	log(kMB′–DNA/s−1)a	log(kNB–DNA/s−1)a	log(kMB′–DNA/s−1)a	log(kNB–DNA/s−1)a
spermidine bufferb	1.6	1.6	0.5 and 1.6e	0.3	0.5	0.6
low salt bufferb	1.2	1.6	−0.2 and 1.6e	N/Ad	0.4	N/Ad

^aThe electron transfer rates were determined by applying Laviron analysis to CV data acquired at scan rates ranging from 50 mV/s to 13 V/s. The uncertainties are ~10% of the log(k) values.⁴⁵

^bLow salt buffer is 5.0 mM phosphate, 50 mM NaCl, and pH 7. Spermidine buffer is 5.0 mM phosphate, 50 mM NaCl, 4 mM MgCl₂, 4 mM spermidine, 50 µM EDTA, 10% glycerol, and pH 7.

^cAssembled overnight with 25 µM of ssDNA (probe strand lacking thiol complement) or dsDNA, with or without 100 mM MgCl₂.

^dThe rate for double-stranded NB–DNA could not be determined in low salt buffer as the signals were too small.

^eTwo distinct reductive peaks were observed for MB′–DNA when assembled without MgCl₂ (Figure 7).