Table 2.

Melting temperatures in °C for modified versus non-modified duplexes

Complementary base	2*A	2*C	2*T	2*G
10 5′-CTGACG A2ATGC-3′	30.9 (−17.2)	24.0 (−28.0)	30.0 (–19.7)	29.3 (−24.1)
11 5′-CTGACG G2GTGC-3′	40.1 (−16.6)	39.6 (−19.7)	36.1 (−17.0)	38.9 (−23.5)
12 5′-CTGACG C2C TGC-3′	30.5 (−23.2)	24.9 (−36.7)	32.5 (−23.8)	32.4 (−26.3)
13 5′-CTGACG T2T TGC-3′	29.2 (−20.5)	23.1 (−30.4)	27.3 (−19.9)	26.5 (−25.2)

Melting curves were recorded at 260 nm with a heating rate of 0.3°C/min. Oligonucleotide concentrations were 2 μM of each strand in 100 mM NaCl and 10 mM phosphate buffer at pH. Values between parentheses refer to destabilization with respect to unmodified duplexes.