Table 1. Reaction Conditions and % of Biotinylation of fU-ODN and fC-ODN with Different Probes.

	probe	conditionsa	fU-ODNb (%)	fC-ODNb (%)
1	1c	p-anisidinef, pH 5, 24 h	>99	94
2	1	pH 5, 24 h	>99	56
3	1	pH 6, 24 h	>99	3
4	1	pH 6, 4 h	98	n.d.g
5	2d	p-anisidinef, pH 6, 24 h	>99	99
6	2	pH 7, 24 h	>99	2
7	2	pH 7, 4 h	>99	n.d.g
8	3e	pH 7, 4 h	93	1

^aReactions were carried out in 40 mM NH₄OAc (entry 1) or in 40 mM sodium phosphate (entries 2–8).

^bConversion was calculated by integration of UV signals of the biotinylated product and the starting material at 260 nm.

^cProbe 1 was used at 0.4 mM.

^dProbe 2 was used at 10 mM.

^eProbe 3 was used at 5 mM.

^fp-Anisidine was used at 100 mM.

^gn.d. = not detected.