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Functional Groups (for ASOs)

 
Functional Groups
Position
 
5’
3’
int
Amino / Amino-dT
on request
on request
on request
Phosphorothioate (PTO)
 
 
X

 

Amino / Amino-dT

A primary amino group can be used to attach a variety of modifiers (such as fluorescent dyes) to an oligonucleotide or used to attach an oligonucleotide to a solid surface. Amino modifiers can be positioned at the 5’-end with either a standard (C6) or longer (C12) spacer arm. Amino modifications can be positioned at the 3’-end. Internal amino modifications can be introduced using an amino-dT base.

 
Functional Group
Position
Synthesis Scale [µmol]
Purification
 
 
0.04
0.2
1.0
15
Des
HPLC
PAGE
Amino C6
5’
X X X X X X X
3’
X X X X X X X
Amino C6-dT
Int
 
X X O
 
X X
X = available/on stock
O = on request
 

Phosphorothioate (PTO)

PTO
 

The phosphorothioate (PTO) bond substitutes a sulfur atom for a non-bridging oxygen in the phosphate backbone of an oligo. This modification renders the internucleotide linkage resistant to nuclease degradation. Phosphorothioate bonds can be introduced between the last 3-5 nucleotides at the 5'- or 3'-end of the oligo to inhibit exonuclease degradation. Including phosphorothioate bonds throughout the entire oligo will help reduce attack by endonucleases as well.

 
Position
Synthesis Scale [µmol]
Purification
 
0.04
0.2
1.0
15
Des
HPLC
PAGE
Int X
X
X
X X
X
X
X = available/on stock
O = on request