Target: Human
Host: Goat
Antibody Format: Fab Fragment
Specificity: IgG, Fcγ fragment specific
Conjugate: Alexa Fluor® 647
Product Category: FabuLight™ - Affinity-Purified Fc Specific Fab Fragments
Clonality: Polyclonal
RRID: AB_2632454

Information

Based on immunoelectrophoresis and/or ELISA, the antibody reacts with the Fc portion of human IgG heavy chain but not with the Fab portion of human IgG. No antibody was detected against human IgM or IgA, or against non-immunoglobulin serum proteins. The antibody may cross-react with immunoglobulins from other species.

Fab fragment antibodies are generated by papain digestion of whole IgG antibodies to remove the entire Fc portion, including the hinge region. These antibodies are monovalent, containing only a single antigen binding site. The molecular weight of Fab fragments is about 50 kDa.

Usage

Physical State: Freeze-dried solid

Storage and Rehydration: Store freeze-dried solid at 2-8°C. Rehydrate with the indicated volume of dH2O (see product specification sheet) and centrifuge if not clear. Prepare working dilution on day of use. Product is stable for about 6 weeks at 2-8°C as an undiluted liquid.
Extended Storage after Rehydration: Aliquot and freeze at -70°C or below. Avoid repeated freezing and thawing. Alternatively, add an equal volume of glycerol (ACS grade or better) for a final concentration of 50%, and store at -20°C as a liquid.
Expiration date: one year from date of rehydration. The expiration date may be extended if test results are acceptable for the intended use.

Purity: The antibody was purified from antisera by a combination of papain digestion and immunoaffinity chromatography using antigens coupled to agarose beads. Fc fragments and whole IgG molecules have been removed.
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:

1:100 - 1:800 for sequential labeling applications.

To complex with primary antibody in solution, use 1:1 weight ratio of Fab:primary antibody (3:1 molar ratio). Vortex and incubate for 30 minutes at room temperature prior to use. Titrate complex to optimal dilution for assay.

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.

Conjugate

Alexa Fluor® 647

Amax: 651 Emax: 667nm

Alexa Fluor® 647-conjugated antibodies absorb light maximally around 651 nm and fluoresce maximally around 667 nm. They are brighter than Cy5 and DyLight 650 in aqueous mounting media. Alexa Fluor® 647- and APC-conjugated secondary antibodies are the best choice for flow cytometry when secondary antibodies fluorescing at these wavelengths are desired. Alexa Fluor® 647 conjugates are the best choice of far red-emitting dyes for multiple-labeling detection with a confocal microscope.

A significant advantage of using Alexa Fluor® 647 over lower wavelength-emitting dyes is the low autofluorescence of biological specimens in this region of the spectrum. However, because of its peak emission at 667 nm, Alexa Fluor® 647 cannot be seen well by eye, and it cannot be excited optimally with a mercury lamp. Therefore, Alexa Fluor® 647 is not recommended for use with conventional epifluorescent microscopes. It is most commonly visualized with a confocal microscope equipped with an appropriate laser for excitation and a far-red detector. Alexa Fluor® 647 conjugates are less expensive alternatives to allophycocyanin conjugates for flow cytometry.

Alexa Fluor® 647-conjugated AffiniPure™ Fab Fragment Goat Anti-Human IgG, Fcγ Fragment Specific