DNA with Fluorescent Modifiers
Custom DNA Oligos
Our specialty modification department is dedicated to the synthesis of modified oligos including optimizing protocols, exploring new chemistries, consulting with customers, and ensuring product quality.
Sigma-Genosys can attach fluorescent dyes to oligos at the 5′-end, 3′-end and even internal positions. Our product offering includes common dye modifiers such as 6-FAM, HEX, and TET, as well as exotic modifications. We are a licensed supplier of modifications from Molecular Probes, Inc., Biosearch Technologies, and PHRI, City of New York.
In addition to standard fluorescent modifications, we have the capabilities to provide dual-labeled probes including Molecular Beacons.
Maximal Absorbance and Emission for Common Fluorophores
Description Max Absorbance (nm) Max Emission (nm) Recommended Purification
- Fluorescein 492 520 Desalt, RP1, HPLC
- 6-FAM 494 525 Desalt, RP1, HPLC
- TET 521 536 Desalt, RP1, HPLC
- HEX 535 556 Desalt, RP1, HPLC
- TAMRA 555 580 HPLC
- Texas Red 595 615 HPLC
- JOE 521 547 Desalt, RP1, HPLC
- Cy5™ 643 667 RP1, HPLC
- Cy3™ 552 570 RP1, HPLC
- BODIPY FL 505 513 HPLC
- Oregon Green 488 493 520 HPLC
Most modifications are available at the 0.05, 0.2, and 1.0 µmole scale. Please call for large scale projects.
Desalt or cartridge (RP1) purification is acceptable for most common phosphoramidite modifiers. However, additional purification such as HPLC is strongly recommended for modifiers that require NHS-ester chemistry to conjugate a dye through an amine linker such as Molecular Probes dyes.
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.
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 specialized 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.
Expected shipment time for common dye modifiers is 3 – 5 working days. More exotic modifications are usually completed within 5 – 7 working days.
Modification pricing is per modification and does not include base charges. Contact your Account Representative for pricing on multiple modifications or to request a large volume quote.
For additional information, please send your request.