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Freedom™ Dyes

For license-free access to patented fluorescent dyes

  • License-free use in commercial or diagnostic applications
  • Proprietary IDT fluorophores for commonly used dye wavelengths
  • Includes fluorescein, Cy®, rhodamine, and ATTO™ dyes
  • Pair with ZEN™ and Iowa Black® quenchers to create probes with lower background and higher signal

Freedom fluorescein dyes

Dye5'Internal3'Excitation
(nm)
Emission
(nm)
Alternative
6-FAM (Fluorescein)detailsdetails495520N/A
6-FAM (NHS Ester)details

details
496516N/A
Fluorescein dTdetails
details
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495520N/A
HEXdetails

538 555 Yakima Yellow®
Yakima Yellowdetails--524551HEX
JOE (NHS Ester)details

details
529 555 MAX (NHS Ester)
MAXdetails

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524 557 JOE (NHS Ester)
TETdetails


522539N/A

6-FAM (Fluorescein): A single isomer derivative of fluorescein. FAM is the most commonly used fluorescent dye attachment for oligonucleotides and is compatible with most fluorescence detection equipment. It becomes protonated and has decreased fluorescence below pH 7; it is typically used in the pH range 7.5–8.5. FAM can be attached to 5' or 3' end of oligos.

6-FAM (NHS Ester): A post-deprotection reaction is used to attach this fluorophore to the oligonucleotide. This is commonly used to modify RNA oligos with FAM.

Fluorescein dT: Fluorescein is attached to position 5 of the thymine ring by a 6-carbon spacer arm.

HEX: Hexachlorofluorescein is a chemical relative of fluorescein that is commonly used for multiplexed assays with FAM and TET. HEX can be added only to the 5' end of an oligonucleotide.

JOE (NHS Ester): JOE (6-carboxy-4',5'-dichloro-2',7'-dimethoxyfluorescein) is available only as an NHS ester and must be attached to an amino-modified oligonucleotide. JOE is frequently used in multiplex reactions with FAM.

MAX (NHS Ester): Most often used to multiplex with FAM. It can be used as a VIC™ substitute because its spectral profile is nearly identical to VIC. Importantly, MAX is efficiently excited by either a 488 nm laser or a broad emission light source; therefore, it can be used with most commercial detection platforms.

TET: Tetrachlorofluorescein is a chemical relative of fluorescein that is commonly used for multiplexed assays with FAM and HEX. TET can be added only to the 5' end of an oligonucleotide.

Freedom Cy dyes

Dye5'Internal3'Excitation
(nm)
Emission
(nm)
Alternative
Cy 3details
details
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550564TYE™ 563
Cy 5details
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648668TYE 665
Cy 5.5details
details
685 706 TYE 705

Cy 3: A standard orange-fluorescent label for nucleic acids used in imaging, flow cytometry, and genomic applications.

Cy 5: A standard far red-fluorescent label for nucleic acids used in imaging, flow cytometry, and genomic applications.

Cy 5.5: Used as a fluorescent label in 5' nuclease probes for qPCR, Scorpion® primers, and Molecular Beacons. Cy 5.5 can also be used to label DNA oligos for use as hybridization probes in other applications, such as fluorescent in situ hybridization (FISH).

Freedom rhodamine dyes

Dye5'Internal3'Excitation
(nm)
Emission
(nm)
Alternative
ROXdetailsdetails588608ATTO Rh101 (NHS Ester)
TAMRA
details
559583N/A
TAMRA™ (NHS Ester)details
details
details
559583N/A
TEX 615details

details
596613Texas Red®-X (NHS Ester)

ROX (NHS Ester): ROX (carboxy-X-rhodamine) is available only as an NHS ester; therefore, it must be attached to an amino-modified oligonucleotide. It has spectral properties similar to Texas Red.

TAMRA: This phosporamidite modification is only available at the 3' end of an oligonucleotide. This was used as a quencher in first generation real-time PCR.

TAMRA (NHS Ester): The internal and 3' versions of this modification are attached to the oligonucleotide through a dT base; therefore, a dT nucleotide will be added at the position of these modifications. To avoid adding an extra nucleotide, replace an existing T nucleotide in your sequence with the required modification.

TEX 615: A red wavelength dye commonly used in multiplex reactions with FAM or in fluorescence-activated cell sorting (FACS) and microscopy applications using the rhodamine filter. TEX 615 can be used as a direct substitute for Texas Red or CAL Fluor 610.

Freedom ATTO Dyes

Dye5'Internal3'Excitation
(nm)
Emission
(nm)
Alternative
ATTO 488details

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502522Alexa Fluor® 488
ATTO 532details
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534554VIC®
ATTO 550details

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560575Alexa Fluor 555
ATTO 565details
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570591PET™
ATTO Rho101details

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592609ROX
ATTO 590details
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602624Alexa Fluor 594
ATTO 633details

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635653LIZ®
ATTO 647Ndetails
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649662Alexa Fluor 647

ATTO dyes are patented fluorescent markers that feature strong absorption and sensitivity, enhanced photostability, and high fluorescence quantum yield. ATTO dyes are perfect substitutes for dyes such as ROX, VIC, LIZ, and Alexa Fluor dyes. The dyes offer alternatives for applications including fluorescence in situ hybridization (FISH), fluorescence resonance energy transfer (FRET), and dual-labeled probes used in real-time PCR experiments. For real-time PCR applications, dye calibration will be needed for each real-time PCR instrument.

Other Freedom Dyes

Dye5'Internal3'Excitation
(nm)
Emission
(nm)
Alternative
TYE 563detailsdetails549563Cy 3
TYE 665details

details
645665Cy 5
TYE 705details


686704Cy 5.5

TYE dyes are proprietary fluorophores from IDT that are available for commonly used dye wavelengths. The numerical value in the name of these dyes represents the emission wavelength when attached to an oligo.

TYE 563: A bright fluorescent dye that can be used in microarray applications. TYE 563 can be used as a direct substitute for Cy 3.

TYE 665: A bright fluorescent dye that can be used in microarray applications. TYE 665 can be used as a direct substitute for Cy 5.

TYE 705: A bright fluorescent dye that can be used in microarray applications. TYE 705 can be used as a direct substitute for Cy 5.5.

Additional fluorophores (which may include licensing restrictions) are available. Click here to see our full catalog of fluorophore modifications.