To minimize cross-reactivity, these donkey anti-goat IgG whole antibodies have been cross-adsorbed against rabbit, rat, mouse, and human IgG. Cross-adsorption or pre-adsorption is a purification step to increase specificity of the antibody resulting in higher sensitivity and less background staining. The secondary antibody solution is passed through a column matrix containing immobilized serum proteins from potentially cross-reactive species. Only the nonspecific-binding secondary antibodies are captured in the column, and the highly specific secondaries flow through. The benefits of this extra step are apparent in multiplexing/multicolor-staining experiments (e.g., flow cytometry) where there is potential cross-reactivity with other primary antibodies or in tissue/cell fluorescent staining experiments where there are may be the presence of endogenous immunoglobulins.
Alexa Fluor dyes are among the most trusted fluorescent dyes available today. Invitrogen™ Alexa Fluor 488 dye is a bright, green-fluorescent dye with excitation ideally suited to the 488 nm laser line. For stable signal generation in imaging and flow cytometry, Alexa Fluor 488 dye is pH-insensitive over a wide molar range. Probes with high fluorescence quantum yield and high photostability allow detection of low-abundance biological structures with great sensitivity. Alexa Fluor 488 dye molecules can be attached to proteins at high molar ratios without significant self-quenching, enabling brighter conjugates and more sensitive detection. The degree of labeling for each conjugate is typically 2-8 fluorophore molecules per IgG molecule; the exact degree of labeling is indicated on the certificate of analysis for each product lot.
Using conjugate solutions: Centrifuge the protein conjugate solution briefly in a microcentrifuge before use; add only the supernatant to the experiment. This step will help eliminate any protein aggregates that may have formed during storage, thereby reducing nonspecific background staining. Because staining protocols vary with application, the appropriate dilution of antibody should be determined empirically. For the fluorophore-labeled antibodies a final concentration of 1-10 µg/mL should be satisfactory for most immunohistochemistry and flow cytometry applications.
Obtain superior images with the new Invitrogen™ Alexa Fluor™ Plus secondary antibodies. Make your low abundant targets visible, minimize time spent optimizing, and make your precious samples count. Alexa Fluor™ Plus secondary antibodies provide brighter signal while having lower cross-reactivity compared to leading Alexa Fluor secondary antibodies, providing you with higher sensitivity and better signal-to-noise for your critical experiments. Alexa Fluor Plus secondary antibodies represent an advancement in fluorescent conjugate technology. Alexa Fluor Plus secondary antibodies are conjugated using new, proprietary dye chemistry and are pre-adsorbed to reduce background and cross-reactivity so you can generate stunning images. Alexa Fluor Plus secondary antibodies provide up to 4.2 fold higher signal-to-background in imaging applications and up to 5.8 fold higher signal-to-background in fluorescent western applications compared to Alexa Fluor secondary conjugates.
For Research Use Only. Not for use in diagnostic procedures. Not for resale without express authorization.