Jackson Immuno Research Europe Ltd
specialising in secondary antibodies and conjugates

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Steptavidin, a bacterial protein isolated from Streptomyces avidinii, is similar to egg-white avidin in its ability to bind biotin, and has been used as a replacement for egg-white avidin because of its more favorable chemical properties.

Conjugates of streptavidin are recommended for use with Biotin-SP-conjugated antibodies and Biotin-SP-conjugated ChromPure proteins.
Physical State: Freeze-dried solid
Storage:

Store freeze-dried powder at 2-8°C. When ready to use, rehydrate with indicated volume of d. water and centrifuge if not clear. Product is stable for about 6 weeks at 2-8°C as an undiluted liquid. Prepare working dilution fresh each day. For extended storage after rehydration, add an equal volume of glycerol (ACS grade or better) for a final concentration of 50%, and store at -20°C as a liquid. Note: after the addition of glycerol, the concentration of protein and buffer salts is one-half of the original. Alternatively, aliquot and freeze the product at -70°C or below in the absence of glycerol. Avoid repeated freezing and thawing.
Expiration date: one year from date of rehydration. However, the expiration date may be extended if the product is stored according to the recommendation and the test results are acceptable for its intended use.


Buffer: 0.01M Sodium Phosphate, 0.25M NaCl, pH 7.6
Stabilizer: 15 mg/ml Bovine Serum Albumin (IgG-Free, Protease-Free)
Preservative: 0.05% Sodium Azide

Suggested Working Concentration or Dilution Range:
Western Blot:- 0.5-2 µg / ml
Histo-/Cyto-Chemistry:- 0.5-2 µg / ml

Dilution factors are presented in the form of a range because the optimal dilution is a function of many factors, such as antigen density, permeability, etc. The actual dilution used must be determined empirically.

Cyanine Cy™3

Amax: 550 Emax: 570nm

Cy3 is brighter, more photostable, and gives less background than other orange-red fluorescing dye conjugates. Cy3 conjugates can be excited maximally at 550 nm, with peak emission at 570 nm. For fluorescence microscopy, Cy3 can be visualized with traditional tetramethyl rhodamine (TRITC) filter sets, since the excitation and emission spectra are nearly identical to those of TRITC. We recommend Cy3 as a brighter alternative to TRITC. Cy3 can be excited to about 50% of maximum with an argon laser (514 nm or 528 nm lines), or to about 75% of maximum with a helium/neon laser (543 nm line) or mercury lamp (546 nm line). Cy3 has been used with fluorescein for double labeling; however, the use of a narrow band-pass emission filter for fluorescein is recommended to minimize Cy3 fluorescence in the FITC filter set. Cy3 can also be paired with Alexa Fluor® 647 for multiple labeling when using a confocal microscope. However, a better choice for multiple labeling is Rhodamine Red-X because its fluorescence is midway between a green fluorescing dye (like Alexa Fluor® 488) and a far-red-fluorescing dye like Alexa Fluor® 647.

Above

Pax2 expression in astrocytes of aged rat retina

Tissue specimen of 19 month old (aged) Wistar rat retina illustrates Pax2 expression in retinal astrocytes in the central retina. Triple label immunohistochemistry was executed on retinal wholemount preparations. Pax2 stained for surrounding nuclei of astrocytes (red, biotinylated anti-rabbit Ig, Cy3-conjugated streptavidin - Jackson ImmunoResearch 016-160-084), DAPI stain for cell nuclei (blue), and GFAP stained for astrocytes (green, Alexa 488-conjugated anti-mouse IgG1).

Mansour, H., Chamberlain, C. G., Weible II, M. W., Hughes, S., Chu, Y. and Chan-Ling, T. (2008), Aging-related changes in astrocytes in the rat retina: imbalance between cell proliferation and cell death reduces astrocyte availability. Aging Cell, 7: 526–540. doi: 10.1111/j.1474-9726.2008.00402.x


Below

Confocal micrograph of the ventral horn in the D9 spinal cord segment of a red-eared turtle (Trachemys scripta elegans). The composite image of an electrophysiologically measured and biocytin-injected motor neuron (red, Cy3 016-160-084), in a population of motor neurons (green, Choline acetyltransferase, Alexa Fluor® 488 705-545-147) with a nuclear staining (blue, DAPI).
Kristian Reveles Jensen, University of Copenhagen.

This product is for IN VITRO RESEARCH USE ONLY. It is not a medical device and it is not intended for diagnostic or therapeutic purposes.

Cy is a trademark of GE Healthcare Bio-Sciences Ltd. Jackson ImmunoResearch is licensed by GE Healthcare Bio-Sciences Ltd. to manufacture and sell conjugates of Cy2, Cy3, and Cy5 reactive dyes under US Patent Number 5,268,486, and other patents pending.