Bio-Synthesis offers Alexa  555 fluorescent dye oligonucleotide labeling services. Alexa 555  is an orange fluorescent dye. This dye often used as a replacemnt for for tetramethylrhodamine or Cy®3 dye, exhibiting greater photostability than Cy®3 dye in live and fixed cells. In addition, is used in stochastic optical reconstruction microscopy (STORM)—as an activator in nSTORM and a reporter in dSTORM.

Characteristic features of the label are high fluorescence quantum yield, and high thermal and photo-stability. The dye sallow detection of low-abundance biological structures with great sensitivity. Alexa Fluor® 568 can be substitute for Cy3 or tetramethylrhodamine (TRITC). This molecules can be attached to oligo at multiple sites at high molar ratios without significant self-quenching, enabling brighter conjugates and more sensitive detection.

  • Red-orange fluorescence
  • Bright and photostable tetramethylrhodamine or Cy3 substitute
  • Spectrally similar to Cy3

Alexa 555 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 555 fluorescent dye oligonucleotide labeling services.

Product Information


Product Name:

Alexa 555 Oligo Labeling


Fluorescent dye Label, Cy3, Tetramethylrhodamine Alternative

Modification Code:


Excitation (nm):

555 nm

Emission (nm):

565 nm

Extinction Coefficient, ε(λ):



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.