Alexa Fluor 350 dyeInvitrogen Alexa Fluor 350 dye is a blue-fluorescent dye with moderate photostability and excitation that matches the 350 nm laser line. The brightness and photostability of blue dyes are best suited to direct imaging of high-abundance targets.

Blue-fluorescent probes provide high-contrast discrimination for quantitative imaging applications without compromising performance in the popular red and blue channels. Alexa Fluor 350 protein conjugates are optimally excited at ~346 nm and produce bright, blue fluorescence at a wavelength slightly shorter than that of AMCA or AMCA conjugates, reducing Alexa Fluor 350 dye’s spectral overlap with the emission of fluorescein or Alexa Fluor 488 dye.

We offer Alexa Fluor 350 dye conjugated to a variety of antibodies, peptides, proteins, tracers, and amplification substrates optimized for cellular labeling and detection. In addition, reactive dye forms and protein labeling kits are available to allow you to generate your own antibody conjugates or probes.

Alexa Fluor 350 dye dashboard

Initial brightness

The brightest dye available in the blue channel is best used for high-abundance targets like cytoskeleton markers. Commonly used with Alexa Fluor 488, 594, and 647 dyes for multiplexing.  

Photostability in buffer


Photostability in antifade



Fixed and permeabilized muntjac skin fibroblasts were stained with Alexa Fluor 350 phalloidin, a Mouse anti–ATP Synthase Subunit IF1 Monoclonal Antibody, an anti–α-tubulin antibody, and an anti–cdc6 peptide antibody.


The Mouse anti–ATP Synthase Subunit IF1 Monoclonal Antibody was prelabeled with the Invitrogen Zenon Alexa Fluor 488 Mouse IgG1 Labeling Kit (green), the anti–a-tubulin antibody was prelabeled with the Zenon Alexa Fluor 568 Mouse IgG1 Labeling Kit (red), and the anti–cdc6 peptide antibody was prelabeled with the Zenon Alexa Fluor 647 Mouse IgG1 Labeling Kit (pink). The image was deconvolved using Huygens software (Scientific Volume Imaging).


Alexa Fluor 350 reactive dyes

Select dye-labeling chemistries for conjugation with the following reactive groups: 

Amine Thiol Aldehyde, ketone, carboxylate, or phosphate

Alexa Fluor 350 protein/antibody labeling kits

Select an optimized labeling kit for your target antibody or protein:

Target protein Kit Cat. No.
Site-specific antibody labeling
<1–20 µg mouse IgG1 Zenon Alexa Fluor 350 Mouse IgG1 Labeling Kit Z25000
<1–20 µg mouse IgG2a Zenon Alexa Fluor 350 Mouse IgG2a Labeling Kit Z25100
<1–20 µg mouse IgG2b Zenon Alexa Fluor 350 Mouse IgG2b Labeling Kit Z25200
<1–20 µg rabbit IgG Zenon Alexa Fluor 350 Rabbit IgG Labeling Kit Z25300
Conventional antibody/protein labeling
100 µg antibody/protein Alexa Fluor 350 Antibody/Protein Labeling Kit A20180
1 mg antibody/protein Alexa Fluor 350 Antibody/Protein Labeling Kit A10170

Alexa Fluor dye family

Illuminating research for over 15 years

Alexa Fluor® dyesAlexa Fluor dyes are among the most trusted fluorescent dyes available today. In addition to superior performance, you’ll get a technical support team experienced in problem-solving, >50,000 published references, application and experimental tips, and protocols to help with experimental planning. For an outstanding research experience, choose Alexa Fluor dyes.



Molecular Probes Handbook

Cell stain tool

The significantly revised 11th Edition is the most complete fluorescence labeling and detection reference available. The Molecular Probes Handbook can help you achieve the best experimental results for your fluorescence labeling and detection experiments. View the handbook online or order your own copy.

Go to the Handbook online
Order your copy of the Handbook

Antifade reagents

Cell stain tool

Antifade reagents suppress photobleaching and preserve the signals of your fluorescently labeled target molecules. They offer excellent compatibility with a multitude of dyes across the spectrum, making them especially valuable tools for multicolor applications. For added convenience, some formulations include the nuclear counterstain DAPI, eliminating the need for a separate counterstaining step.

Learn more about SlowFade Antifade reagents
Learn more about ProLong Antifade reagents

Cell stain tool

Cell stain tool

Stain your own cell by using our simulation tool to develop reproducible results with many of our signature fluorescent dyes. Develop your multiplexing strategy for antibody probes, reactive dyes, and counterstains to create your perfectly labeled fluorescent cell.

Go to the cell stain tool

Fluorescence SpectraViewer


Plot and compare spectra and check the spectral compatibility for common fluorophores including all of the fluorescent probes from Thermo Fisher Scientific. The Fluorescence SpectraViewer tool is formatted for both microscope imaging and flow cytometry applications.

Go to the Fluorescence SpectraViewer

Not for resale. Super Bright Polymer Dyes are sold under license from Becton, Dickinson and Company.