An alternative to avidin and streptavidin that performs better and costs less.

Thermo Scientific NeutrAvidin Protein is a deglycosylated form of avidin biotin-binding protein. Removal of the excess carbohydrate from by an exclusive process yields a protein with a more neutral isoelectric point and less nonspecific binding properties than native avidin. Purified and conjugated forms of NeutrAvidin Protein provide exceptional performance in Western blot, ELISA and IHC applications that require biotin-binding probes. Assay specificity, sensitivity, and signal-to-noise ratios with NeutrAvidin Protein are generally equivalent or better than with the significantly more expensive streptavidin.

Dont let throw money out the window by using streptavidin conjugates when value-priced NeutrAvidin Protein conjugates will provide equal or better assay performance!

 

Avidin is a glycoprotein found in the egg white and tissues of birds, reptiles and amphibia. The biotin-binding protein contains four identical subunits having a combined mass of 67,000-68,000 daltons. Removing the glycosylation from avidin yields NeutrAvidin Protein with a mass of 60,000 daltons. Carbohydrate-based lectin-binding is reduced to undetectable levels, yet biotin-binding affinity is retained. NeutrAvidin Protein offers the advantages of a neutral pI to minimize nonspecific adsorption, along with lysine residues that remain available for derivatization or other customized conjugation. NeutrAvidin Protein yields the lowest nonspecific binding among the known biotin binding proteins. The specific activity for biotin-binding is approximately 14 µg/mg of protein, which is near the theoretical maximum activity.

Highlights of NeutrAvidin Biotin-Binding Protein:

• Near-neutral isoelectric point – pI = 6.3, more neutral than native avidin
• Nearly devoid of glycosylation – decreased possibility of lectin binding like avidin
• No RYD recognition sequence – no known off-target binding domains like streptavidin
• Affordable – significantly less expensive than streptavidin
• Available in multiple formats – choose purified NeutrAvidin Protein, prepared HRP and AP conjugates or activated forms for immediate use or customized application in a variety of techniques. Also available are NeutrAvidin Protein Agarose and UltraLink Resins and Coated Microplates.

Comparison of available biotin-binding proteins.
	Avidin	Streptavidin	NeutrAvidin Protein
Molecular Weight	67K	53K	60K
Biotin-binding Sites	4	4	4
Isoelectric Point (pI)	10	6.8-7.5	6.3
Specificity	Low	High	Highest
Affinity for Biotin (Kd)	10-15 M	10-15 M	10-15 M
Nonspecific Binding	High	Low	Lowest

Applications for NeutrAvidin Protein:

• Western blotting – use NeutrAvidin Protein Conjugates (HRP or AP) instead of streptavidin conjugates for detection of biotinylated target proteins or biotinylated primary or secondary antibodies in Western blots.
• ELISA – NeutrAvidin Protein Conjugates (HRP or AP) replace corresponding streptavidin conjugates for direct or indirect sandwich ELISA detection schemes involving biotin-labeled proteins and antibodies. Depending on the specific assay components (e.g., blocking buffers, etc.), NeutrAvidin Protein Conjugates provide similar or better assay performance measured as signal-to-noise ratio.
• Immunohistochemistry – try NeutrAvidin Protein in place of avidin in customized IHC detection systems, including signal-amplification methods like the avidin-biotin complex (ABC) technique. Depending on other assay components, decreased background and lower limits of detection may be possible.
• In Situ Hybridization – NeutrAvidin-AP Conjugate is currently being used by the Allen Institute for Brain Science to create the Allen Brain Atlas.

  Product #	Description	Pkg. Size
  31000	NeutrAvidin Protein 11-17 µg biotin bound/mg NeutrAvidin Protein	10 mg
  31050	NeutrAvidin Protein 11-17 µg biotin bound/mg NeutrAvidin Protein	100 mg
  31055	NeutrAvidin Protein 11-17 µg biotin bound/mg NeutrAvidin Protein	1,000 mg
  31001	NeutrAvidin Protein, Horseradish Peroxidase Conjugated 1-2 moles HRP/mole NeutrAvidin Protein 3-8 µg biotin bound/mg conjugate Also consider our High Sensitivity NeutrAvidin-HRP Conjugates	2 mg
  31002	NeutrAvidin Protein, Alkaline Phosphatase Conjugated 3-8 µg biotin bound/mg conjugate	2 mg
  31006	NeutrAvidin Protein, Fluorescein Conjugated Absorption: 490 nm; Emission 520 nm >2 moles fluorescein/mole NeutrAvidin Protein Also consider our complete line of DyLight Fluor NeutrAvidin Conjugates	5 mg
  31007	Maleimide Activated NeutrAvidin Protein for conjugation to sulfhydryl groups on antibodies and other molecules. 4-8 moles maleimide/mole NeutrAvidin Protein	5 mg