Bio-Synthesis offers Alexa 405 fluorescent dye oligonucleotide labeling services. Alexa 405 is a blue-fluorescent dye with excitation ideally suited for the 407 nm spectral line of the krypton laser or the 408 nm violet laser diode. This dye is pH-insensitive over a wide molar range which ensure stable signals in live-cell imaging application.  The fluorescence conjugates has peak excitation wavelength in 401nm and emission wavelength in 421 nm. Alexa Fluor® 405 dye provides versatility in the blue channel for imaging and is compatible with the violet laser for flow cytometry. It is extremely useful in stochastic optical reconstruction microscopy (STORM) where it is used as an activator. It is also used to label conjugates for SIM, STED and TPE.

  • Cascade Blue derivative containing a spacer between the fluorophore and the reactive SE
  • Near-perfect match to the 405 nm violet diode laser
  • Absorption at 402 nm
  • Emission at 421 nm

Alexa 405 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 405 fluorescent dye oligonucleotide labeling services.

Product Information


Product Name:

Alexa 405 Oligo Labeling


Fluorescent dye Label

Modification Code:


Chemical Formula:


Exact Mass:


Formula Weight:


Excitation (nm):

402 nm

Emission (nm):

421 nm

Extinction Coefficient, ε(λ):



Bio-Synthesis Inc. Oligo Structure


dual HPLC

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.