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Life Science > Custom Oligos > Custom DNA Oligos > Product Lines > Additional Modifications
Custom DNA Oligos

Additional Modifications

 

Whether your application requires amine modifiers for attachment or biotin for detection assays, we are prepared to meet your needs.

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Capabilities
Sigma-Genosys can attach oligo modifications at the 5'-end, 3'-end and even internal positions.  In addition to fluorescent dyes and dual-labeled probes, our modifications include: 

Description  Position Available Recommended Purification
Amine C3 5'  Desalt, RP1, HPLC
Amine C6  5'  Desalt, RP1, HPLC
Amine C12  5'  Desalt, RP1, HPLC
Amino dT  5', Internal  Desalt, RP1, HPLC 
Biotin-TEG  3', 5', Internal  Desalt, RP1, HPLC 
Biotin  5'  Desalt, RP1, HPLC 
Biotin dT  3', 5', Internal  Desalt, RP1, HPLC 
Phosphorylation  3', 5'  Desalt, PAGE 
Phosphorothioate (Antisense Oligos) 3', 5', Internal  Desalt, RP1, HPLC 
dI  3', 5', Internal  Desalt, RP1, HPLC 
dU  3', 5', Internal  Desalt, RP1, HPLC 
Spacer 9 5', Internal Desalt, RP1, HPLC 
Spacer C3 3', 5', Internal Desalt, RP1, HPLC 
Thiol C6 S-S 5', Internal Desalt, RP1, HPLC

Synthesis Scales
Most modifications are available at the 0.05, 0.2, and 1.0 µmole scale.  Please call for large scale projects.

Purification
Desalt or cartridge (RP1) purification is acceptable for most common phosphoramidite modifiers.  However, additional purification is strongly recommended for modifiers that require NHS-ester chemistry to conjugate a dye through an amine linker such as Molecular Probes dyes.

Pricing
Contact your local Sigma office for pricing and availability.

Minimum Yield
Due to the chemistry of many modifications, yield will be approximately 40 - 60 % less than a standard oligo.  Please see our yield chart for details.

Quality
Every oligo synthesized is strictly controlled for quality by using either MALDI-TOF mass spectrometry or polyacrylamide gel electrophoresis (PAGE) analysis.  Final yields are determined using UV absorbance at OD260.  In addition, we perform QC methods tailored to specific modifications, such as OD ratio measurement where appropriate. 

You will receive a Quality Assurance Certificate that includes quantitated yield, melting temperature, MW and µg/OD with every oligo.  You will also receive an additional label for use in your records or on an additional vial. 

Shipping Schedule
Expected shipment time for common dye modifiers is 5 working days.  More complicated modifications are usually completed within 5 - 7 working days. Visit our shipping schedule for more details.

For additional information, please send your request to ginformation@sial.com
or call us at 1-800-234-5DNA (5362).