. Author manuscript; available in PMC: 2012 Oct 19.

Published in final edited form as: J Am Chem Soc. 2011 Sep 22;133(41):16642–16649. doi: 10.1021/ja207086x

Table 3.

3′-Exonuclease stability of the phosphosphodiester linkage in DNA, MOE, LNA, FHNA and Ara-FHNA modified oligonucleotides

Sequence (5′–3′)	Modification ^a	T _1/2 (min) ^b
TTTTTTTTTTTT	DNA	0.23
TTTTTTTTTTtt	MOE	3
TTTTTTTTTTtt	LNA	3
TTTTTTTTTTtt	FHNA	160
TTTTTTTTTTtt	Ara-FHNA	101

Uppercase letters indicate 2′-deoxynucleotides, bold letters indicate modified nucleotides, MOE indicates 2′-O-methoxyethyl ribose modification

Each oligonucleotide was prepared as a 500 μL mixture containing: 12.5 μL 200 μM oligomer, 50 μL SVDP at 0.005 Units/mL in SVPD buffer (50 mM Tris-HCl, pH 7.5, 8 mM MgCl2) final concentration 0.0005 Units/mL, 438.5 μL SVP buffer. Samples were incubated at 37°C in a thermoblock. Aliquots (50 μL) were taken at different intervals. EDTA was added to aliquots immediately after removal to quench enzyme activity and the samples were analyzed on IP HPLC/MS. The results are expressed as half-life (T_1/2) in minutes.