Bio-Synthesis offers Alexa 647 fluorescent dye oligonucleotide labeling services. Alexa 647 is a bright far red fluorescent dye that can be excited using the 594 nm or 633 nm laser lines. This dye is pH insensitive over a wide molar range which ensure stable signal generation in imaging and flow cytometry.

Characteristic features of the label are  high fluorescence quantum yield, and high thermal and photo-stability that allow detection of low-abundance biological structures with great sensitivity. Alexa Fluor® 647 is an alternative dye for Cy5. This molecules can be attached to oligo at multiple sites without significant self-quenching, enabling brighter conjugates and more sensitive detection.

  • Far-red fluorescence
  • Produces conjugates that are brighter than those of the Cy5 dye
  • pH-insensitive fluorescence between pH 4 and 10

Alexa 647 dye can be incorporated at any position within an Oligonucleotide. A primary amine modified oligonucleotide is used to covalently attach with dye via NHS conjugation chemistry; other cross-linking chemistries are also available depending on particular project specifications. Dual HPLC purification is used to remove failure sequences during first HPLC purification,  after labeling, the second HPLC is performed to remove unlabeled oligonucleotides and excessive dye in order to obtain a full length labeled oligonucleotide.

Contact us for Alexa 647 fluorescent dye oligonucleotide labeling services.

Product Information


Product Name:

Alexa 647 Oligo Labeling


Fluorescent dye Label, Cy5

Modification Code:


Excitation (nm):

650 nm

Emission (nm):

6665 nm


Dual HPLC required

Delivery Format:


Shipping Conditions:

Room Temperature

Storage Conditions:

-20°C To -70°C
Oligonucleotides are stable in solution at 4°C for up to 2 weeks. Properly reconstituted material stored at -20°C should be stable for at least 6 months. Dried DNA (when kept at -20°C) in a nuclease-free environment should be stable for years.