[Skip to Content](https://www.sigmaaldrich.com#main-content) [![MilliporeSigma](https://www.sigmaaldrich.com/static/logos/purple/millipore_sigma.svg)](https://www.sigmaaldrich.com/US/en) Products Cart0 USEN Products ProductsApplicationsServicesResourcesSupport [Login / Register](https://www.sigmaaldrich.com/oidc-sign-in) [Order Lookup](https://www.sigmaaldrich.com/US/en/order-lookup) [Quick Order](https://www.sigmaaldrich.com/US/en/quick-order) Cart0 [Home](https://www.sigmaaldrich.com/US/en)[qPCR](https://www.sigmaaldrich.com/US/en/applications/genomics/qpcr)Custom Oligos Modifications # Custom Oligos Modifications We offer over 200 modifications for both DNA and RNA oligonucleotides and probes. We can attach fluorescent dyes to oligos at the 5'-end, 3'-end and internal positions. Our product offering includes common dye modifiers such as 6-FAM™, HEX™, and TET™, as well as exotic modifications. In addition to standard fluorescent modifications, we have the capabilities to provide [D](https://www.sigmaaldrich.com/US/en/custom-pdp/de44feb2-4e6f-47f8-9549-adff8bf4a39c)[ual-Labeled Probes](https://www.sigmaaldrich.com/US/en/custom-pdp/de44feb2-4e6f-47f8-9549-adff8bf4a39c) including Molecular Beacons, LightCycler® Probes, and Scorpions® Probes. - [Minimum Yield Guarantees](https://www.sigmaaldrich.com#yield) - [Shipping Schedule](https://www.sigmaaldrich.com#shipping) - [Quality Control](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/genomics/pcr/custom-dna-oligos-qc-qa) Modification Categories - [Fluorescent](https://www.sigmaaldrich.com#fluorescent) - [Attachment](https://www.sigmaaldrich.com#attachment) - [Binding](https://www.sigmaaldrich.com#binding) - [Spacer](https://www.sigmaaldrich.com#spacer) - [Analog](https://www.sigmaaldrich.com#analog) - [Intercalation](https://www.sigmaaldrich.com#intercalation) - [Antisense](https://www.sigmaaldrich.com#antisense) - [Phosphorothioates](https://www.sigmaaldrich.com#phosphorothioates) [Modification Technical Overview (PDF)](https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/marketing/global/documents/390/354/custom-oligos-modifications-ms.pdf) [](https://www.sigmaaldrich.com)FluorescentPositionsExcitation Maximum (nm)Emission Maximum (nm)Fluorescent Color 6-FAM™ (fluorescein)5' End, 3' End495520Green ROX™5' End, 3' End586610Orange Cyanine 35' End, 3' End549566Green-Yellow Cyanine 55' End, 3' End646669Red Cyanine 5.55' End675694Red 6-FAM dT5' End, Internal495520Green HEX™5' End535556Green JOE™5' End, 3' End529555Green 6-Carboxy-rhodamine 6G™5' End, 3' End524550Green TAMRA3' End557583Green-Yellow TAMRA NHS Ester5' End557583Yellow TET™5' End521536Green TxRd (Sulforhodamine 101-X)5' End, 3' End597616Red-Orange A488 (Sulfonated Fluorescein 488)5' End, 3' End495519Green [WellRED D2-PA](https://www.sigmaaldrich.com/US/en/custom-pdp/f2caf8b5-d59f-4814-beed-aaea667a16ab)5' End750770Red-Infrared [WellRED D3-PA](https://www.sigmaaldrich.com/US/en/custom-pdp/f2caf8b5-d59f-4814-beed-aaea667a16ab)5' End685706Red [WellRED D4-PA](https://www.sigmaaldrich.com/US/en/custom-pdp/f2caf8b5-d59f-4814-beed-aaea667a16ab)5' End650670Red [](https://www.sigmaaldrich.com)AttachmentPositionsPurifications   __Amine__      DMS(O)MT-Amino-Modifier-C65' EndCartridge, HPLC  Amino-Modifier-C3-TFA5' EndDesalt, HPLC  Amino-Modifier-C125' EndCartridge, HPLC  Amino-Modifier-C6-TFA5' EndDesalt, PAGE  Amino-dT5' EndCartridge, HPLC  Amino-Modifier-55' EndCartridge, HPLC  Amino-Modifier-C2-dTInternalDesalt, Cartridge, HPLC, PAGE  Amino-Modifier-C6-dTInternalDesalt, Cartridge, HPLC, PAGE  3'-Amino-Modifier-C73' EndDesalt, Cartridge, HPLC, PAGE  __Glycerol__     Glyceryl3' EndDesalt, Cartridge, HPLC, PAGE  __Phosphate__     Phosphate3', 5' EndDesalt, PAGE (5') Desalt, Cartridge, HPLC, PAGE (3') Phosphate II 5' EndCartridge, HPLC  __Thiol__     5'-Thiol-Modifier C6 S-S5' End, InternalCartridge, HPLC  3'-Thiol-Modifier-C3 S-S3' EndDesalt, Cartridge, HPLC, PAGE  [](https://www.sigmaaldrich.com)BindingPositionsPurifications   __Biotin__     5'-Biotin5' EndDesalt, Cartridge, HPLC, PAGE  BiotinInternalHPLC, PAGE  Biotin-dT5' End, InternalHPLC, PAGE  Biotin-TEG5' End, InternalCartridge, HPLC  3'-Biotin-TEG3' EndHPLC, PAGE  __Digoxigenin__     Digoxigenin5' End, 3' End HPLC   __Dinitrophenol__     2,4-Dinitrophenyl-TEG5' End, InternalHPLC   [](https://www.sigmaaldrich.com)SpacerPositionsPurifications   __Spacer__     Spacer 95' End, InternalDesalt, Cartridge, HPLC, PAGE  Spacer 125' End, InternalDesalt, Cartridge, HPLC, PAGE  Spacer 185' End, InternalDesalt, Cartridge, HPLC, PAGE  Spacer C35' End, InternalDesalt, Cartridge, HPLC, PAGE  3'-Spacer-C33' EndDesalt, Cartridge, HPLC, PAGE  [](https://www.sigmaaldrich.com)AnalogPositionsPurifications   __Chain Terminating__     3'-dA3' EndDesalt, Cartridge, HPLC, PAGE  3'-dG3' EndDesalt, Cartridge, HPLC, PAGE  3'-dC3' EndDesalt, Cartridge, HPLC, PAGE  3'-dT3' EndDesalt, Cartridge, HPLC, PAGE  __Chemotherapeutic__     Cytosine Arabinoside (araC)InternalDesalt, Cartridge, HPLC, PAGE  2',3'-dideoxycytidine (ddC)3' EndDesalt, Cartridge, HPLC, PAGE  __Contamination Prevention__    Ribo U3' EndDesalt, Cartridge, HPLC, PAGE  __Crosslinking__     8-Br-dA5' End, InternalDesalt, Cartridge, HPLC, PAGE  8-Br-dG5' End, InternalDesalt, Cartridge, HPLC, PAGE  5-Br-dC5' End, InternalDesalt, Cartridge, HPLC, PAGE  5-Br-dU5' End, InternalDesalt, Cartridge, HPLC, PAGE  5-F-dU5' End, InternalDesalt, Cartridge, HPLC, PAGE  5-I-dC5' End, InternalDesalt, Cartridge, HPLC, PAGE  5-I-dU5' End, InternalDesalt, Cartridge, HPLC, PAGE  __Damage and Repair__      2'-Deoxypseudouridine5' End, InternalDesalt, Cartridge, HPLC, PAGE  5,6-Dihydro-dT5' End, InternalDesalt, Cartridge, HPLC, PAGE  5,6-Dihydro-dU5' End, InternalDesalt, Cartridge, HPLC, PAGE  5-OH-dC5' End, InternalDesalt, Cartridge, HPLC, PAGE  5-OH-dU5' End, InternalDesalt, Cartridge, HPLC, PAGE  8-Oxo-dA5' End, InternalDesalt, Cartridge, HPLC, PAGE  8-Oxo-dG5' End, InternalDesalt, Cartridge, HPLC, PAGE  Thymidine Glycol5' End, InternalPAGE   TMP-F-dU, F-dCInternalDesalt, Cartridge, HPLC, PAGE  dUracil5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  __Degenerate__      2'-Deoxynebularine5' End, InternalCartridge, HPLC, PAGE  Derivative K (dK)5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  Derivative P (dP)5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  Inosine5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  5-Nitroindole5' End, Internal, 5' EndDesalt, Cartridge, HPLC, PAGE  3-Nitropyrrole5' End, Internal, 3' EndDesalt (Internal only), Cartridge, HPLC, PAGE __Duplex Stabilizing__      2,6-Diaminopurine5' End, InternalDesalt, Cartridge, HPLC, PAGE  5-Me-dC5' End, InternalDesalt, Cartridge, HPLC, PAGE  __Fluorescent__      2-Aminopurine5' End, InternalDesalt, Cartridge, HPLC, PAGE  Etheno-dA5' End, InternalDesalt, Cartridge, HPLC, PAGE  __Hybridization Specificity__ [Locked Nucleic Acid](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/genomics/pcr/locked-nucleic-acids-faq)5' End, Internal, 3' EndCartridge, HPLC, PAGE  __Methylation Mutagenesis__     N6-Me-dA5' End, InternalDesalt, Cartridge, HPLC, PAGE  O6-Me-dG5' End, InternalDesalt, Cartridge, HPLC, PAGE  O4-Me-dT5' End, InternalDesalt, Cartridge, HPLC, PAGE  __No Base__      dSpacerInternalDesalt, Cartridge, HPLC, PAGE  __siRNA Guide Strand Selection__     5'-OMe-dT5' EndDesalt, HPLC, PAGE  __Structure and Function__     7-Deaza-dA5' End, InternalDesalt, Cartridge, HPLC, PAGE  7-Deaza-dG5' End, InternalDesalt, Cartridge, HPLC, PAGE  7-Deaza-dX5' End, InternalDesalt, Cartridge, HPLC, PAGE  7-Deaza-8-Aza-dA5' End, InternalDesalt, Cartridge, HPLC, PAGE  dA-5' (Inverse Oligo)5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  dG-5' (Inverse Oligo)5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  dC-5' (Inverse Oligo)5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  dT-5' (Inverse Oligo)5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  __Translation Termination__     Puromycin3' EndDesalt, Cartridge, HPLC, PAGE  [](https://www.sigmaaldrich.com)IntercalationPositionsPurifications   __Acridine__      AcridineInternalDesalt, Cartridge, HPLC, PAGE  __Psoralen__      C25' EndDesalt, Cartridge, HPLC, PAGE  C65' EndDesalt, Cartridge, HPLC, PAGE  [](https://www.sigmaaldrich.com)AntisensePositionsPurifications   __Cholesterol__      Cholesteryl-TEG5' End, InternalCartridge, HPLC  3'-Cholesteryl-TEG3' EndDesalt, Cartridge, HPLC, PAGE  __Methyl RNA__      2'-OMe-RNA A5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  2'-OMe-RNA G5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  2'-OMe-RNA C5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  2'-OMe-RNA U5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  __Methoxyethyl RNA__    2'-MOE-RNA A5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  2'-MOE-RNA G5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  2'-MOE-RNA C5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  2'-MOE-RNA U5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  __Fluoro RNA__    2'-F-RNA A5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  2'-F-RNA G5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  2'-F-RNA C5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  2'-F-RNA U5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  __Thiophosphate__      Thiophosphate (S-Oligo)5' End, Internal, 3' EndDesalt, Cartridge (5' End, Internal) Desalt, Cartridge, HPLC, PAGE (3' End) __2'__ → __5' Synthesis__      dA-5'5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  dG-5'5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  dC-5'5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  dT-5'5' End, Internal, 3' EndDesalt, Cartridge, HPLC, PAGE  ## Phosphorothioates (or S-oligos) [Phosphorothioates (or S-oligos)](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/genomics/gene-expression-and-silencing/phosphorothioates) are a variant of normal DNA in which one of the non-bridging oxygens is replaced by sulfur. The sulfurization of the internucleotide bond creates a molecule that is resistant to cellular nuclease degradation. Sulfur bonds can be introduced at the 5’, 3’, or internal positions. [](https://www.sigmaaldrich.com) ### Minimum Yield Guarantees __Modified Oligos (O.D./µg)\*__ __Scale (µmole)____Desalt____Cartridge____HPLC____PAGE__ 0.052/600.4/120.4/120.2/6 0.25/1501/301/300.4/12 1.016/4805/1505/1502/60 10160/4,800NA52/1,560NA 15240/7,200NA76/2,280NA *\*Guarantees are for 20 mers or longer.  Oligos shorter than 20 bases will have fewer ODs. Microgram amounts are calculated based on a 30 μg/OD value.  If the μg/OD value is less than 30, the reported μg value will be proportionally less. Phosphorothioated yields are 70% of the above stated values. Post-synthesis modifications may yield 50% less than the above stated values.* | | | | | | |------------------------------------------------------------|------------|---------------|-----------|-----------| | __Non-Modified Phosphorothioates (S-Oligos) (O.D./µg )\*__ | | | | | | __Scale (µmole)__ | __Desalt__ | __Cartridge__ | __HPLC__ | __PAGE__ | | 0.05 | 3.5/105 | 0.7/21 | 0.7/21 | 0.35/10.5 | | 0.2 | 8.4/252 | 2.1/63 | 1.75/52.5 | 0.7/21 | | 1.0 | 28/840 | 8.4/252 | 9.1/273 | 3.5/105 | | 10 | 280/8,400 | NA | 91/2,730 | NA | | 15 | 420/12,600 | NA | 133/3,990 | NA | \*Guarantees are for 20 mers or longer. Oligos shorter than 20 bases will have fewer ODs. Microgram amounts are calculated based on a 30 μg/OD value. If the μg/OD value is less than 30, the reported μg value will be proportionally less. [](https://www.sigmaaldrich.com) ### Shipping Schedule __Purification____Desalt____Cartridge____HPLC____PAGE__ Standard Modifications5-7 days or less5-7 days or less5-7 days or lessInquire Post-Synthesis Modifications7-10 days7-10 days7-10 daysInquire \*For complete label license information, please visit [sigmaaldrich.com/oligolicenses](https://www.sigmaaldrich.com/technical-documents/articles/biology/label-licenses.html). [](https://www.sigmaaldrich.com) ## Materials Sorry, an unexpected error has occurred Response not successful: Received status code 500 __Related Articles__ - [PCR/qPCR/dPCR Assay Design](https://www.sigmaaldrich.com/US/en/technical-documents/protocol/genomics/pcr/pcr-qpcr-dpcr-assay-design) - [Cas9-Mediated Recombineering for Kdo2-Lipid A](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/genomics/advanced-gene-editing/crispr-cas-systems) - [Mgat4 May Play a Role in Increased Sialylation by Overexpressing Functional MGAT1 in Mgat1-Disrupted Chinese Hamster Ovary (CHO) Cells](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/genomics/cloning-and-expression/mgat1-disrupted-chinese-hamster-ovary-cells) - [Plasmid Product Nomenclature](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/genomics/cloning-and-expression/plasmid-nomenclature) - [Impact of GenElute™-E Purification on DNA Processes](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/genomics/dna-and-rna-purification/dna-purification-methods) - [Extract-N-Amp™ Plant PCR Kits](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/genomics/dna-and-rna-purification/extract-n-amp-plant-kits) - [Complete Solutions for PCR Assay Development](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/genomics/dna-and-rna-purification/pcr-assay-development) - [Genomic DNA Preparation Troubleshooting](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/genomics/dna-and-rna-purification/problems-during-genomic-dna-preparation) - [View More](https://www.sigmaaldrich.com/US/en/search/facet-search?focus=sitecontent&term=facet-search) __Related Product Categories__ - [Custom DNA Oligos & qPCR Probes](https://www.sigmaaldrich.com/US/en/products/molecular-biology-and-functional-genomics/oligos-and-qpcr-probes/custom-predesigned-dna-oligos-and-qpcr-probes) Top __Sign In To Continue__ To continue reading please sign in or create an account. 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