Dendrimers are discrete, highly branched, monodispersed polymers that possess patterns reminiscent of the branching of trees. Plain and mixed oligonucleotide dendrimers can be synthesized using novel doubling and trebling phosphoramidite synthons.1,2 Dendrimers offer the following advantages. Incorporation of label using g-32P-ATP and polynucleotide kinase increases in proportion to the number of 5'-ends. Fluorescent signal also increases in proportion to the number of 5'-ends, if spacers are incorporated between the labels and the ends of the branches. When using a dendrimeric oligonucleotide as a PCR primer, the strand bearing the dendrimer is resistant to degradation by T7 Gene 6 exonuclease making it easy to convert the double-stranded product of the PCR to a multiply labelled, single-stranded probe. Enhanced stability of DNA dendrimers makes them useful as building blocks for the 'bottom up' approach to nano-assembly. These features also suggest applications in DNA chip technology when higher temperatures are required, for example, to melt secondary structure in the target.
Details
Usage
Coupling: Synthesis should be carried out on 1000A support. A 15 minute coupling time using DCI activator (30-3150-xx) is recommended for the trebler addition.
Deprotection: No changes needed from standard method recommended by synthesizer manufacturer.
Specifications
Diluent
Anhydrous Acetonitrile
Storage
Refrigerated storage, maximum of 2-8°C, dry
Stability
2-3 days
Dilution/Coupling Data
The table below show pack size data and, for solutions, dilution and approximate coupling based on normal priming procedures.
ABI 392/394
Catalog #
Pack Size
Grams/Pack
0.1M Dil. (mL)
Approximate Number of Additions
LV40
LV200
40nm
0.2μm
1μm
10μm
10-1922-02
0.25 g
.25grams
1.76
45.33
27.2
17
12.36
9.07
2.27
10-1922-90
100 µmol
.142grams
1
20
12
7.5
5.45
4
1
Expedite
Catalog #
Pack Size
Grams/Pack
Dilution (mL)
Approximate Number of Additions
Molarity
50nm
0.2μm
1μm
15μm
10-1922-02
0.25 g
.25grams
2.63
0.07
46.2
28.88
21
2.89
10-1922-90
100 µmol
.142grams
1.5
0.07
23.6
14.75
10.73
1.48
References
1 M.S. Shchepinov, I.A. Udalova, A.J. Bridgman, and E.M. Southern, Nucleic Acids Res, 1997, 25, 4447- 4454. 2 M.S. Shchepinov, K.U. Mir, J.K. Elder, M.D. Frank-Kamenetskii, and E.M. Southern, Nucleic Acids Res, 1999, 27, 3035-41.