Antibody Labeling and Conjugation
Labeled and conjugated antibodies streamline assay development and provide faster, more efficient experiments. Proteintech offers conjugated antibodies and a variety of solutions for labeling or conjugating your own unlabeled antibody for direct labeling as well as secondary antibodies for indirect labeling. Whether you are optimizing for signal amplification, convenience, lot-to-lot consistency, quantitative fluorophore-to-protein ratio, or conjugated antibody stability, we have the conjugation solution for you.
Pre-conjugated Antibodies
Conjugated antibodies are the most convenient choice when it comes to simplifying your protocol and multiplexing in performing immunoassays.
Proteintech employs two methods to conjugate antibodies: traditional chemical conjugation and site-specific AccuBright conjugation. Chemical conjugation uses NHS ester or maleimide chemistry. This traditional conjugation method generates antibodies with a range of degree-of-labeling (DOL). The placement of conjugates on the antibody is not known, though each lot is validated using the listed applications on each product page to ensure functionality of the conjugated antibody.
AccuBright conjugation relies on a recombinantly engineered antibody backbone to add conjugation sites at the base of the Fc region. Linked fluorophores or biotin are conjugated enzymatically to the conjugation site. This results in site-specific and stoichiometric conjugation in which the DOL is consistent lot-to-lot.
| Chemical Conjugation | AccuBright Conjugation | |
|---|---|---|
| Available conjugates | CoraLite and CoraLite Plus dyes, FITC, PE, APC, tandem dyes, Biotin, HRP | CoraLite Plus dyes, FITC, PE, APC, tandem dyes, Biotin |
| Applications | WB, IHC, IF, FC, and ELISA | FC |
| Which antibodies | Most Proteintech polyclonal, monoclonal, and recombinant antibodies | FcZero-rAb Recombinant Antibodies and scFv |
| Lot-to-lot consistency | Variable. Each lot is validated in listed applications. | Identical between lots |
Antibody Conjugation and Labeling Kits
FlexAble Antibody Labeling Kits facilitate labeling of antibodies via an easy 15 min protocol, using a high affinity isotype & Fc specific peptide-linker that carries 5 fluorescent dyes (FlexAble 2.0) or 1 or 2 functional groups for attaching functionalized molecules, i.e. Oligos (FlexAble Oligo-Ready). The linker attaches to the Fc fragment with picomolar affinity and high IgG species and isotype specificity, making FlexAble the ideal tool for multiplexing.
FlexAble labeling reactions require as little as 0.5 µg of primary antibody per reaction and work in all common antibody buffers without prior purification.
ChemBright Antibody Labeling Kit
ChemBright is a chemical conjugation kit designed to covalently label an antibody in PBS-only buffer to a CoraLite Plus fluorophore. It is a simple 6-step, 55-minute protocol that does not require column purification, so there is no antibody loss during the conjugation process.
Antibodies conjugated with ChemBright can be stored at 4°C for up to a year.
| ChemBright Antibody Conjugation Kit | FlexAble 2.0 Antibody Labeling Kit | |
|---|---|---|
| Chemistry | Covalent Bond | Affinity Linker |
| Buffer | PBS-only, <0.1% BSA | Any buffer |
| Min. Amount | 100 µg / reaction | 0.5 µg / reaction |
| Antibody type | Any IgG | Isotype Specific, depends on kit |
| Protocol Length | 1 hour | 15 minutes |
| Conjugated Ab Storage | 1 year at 4 °C | Not recommended (use right away) |
| Colors | CoraLite Plus 488 and 647, more to come | CoraLite Plus 405 – 750, FITC, HRP, Biotin, Oligo |
| Kit Storage | 1 year at room temperature (20–25 °C) | −20 °C for 1 year or 4 °C for 6 months |
| Site-specificity | No | Yes |
| Degree of labeling | Variable | Defined |
Secondary Antibodies
Secondary antibodies are the traditional solution to antibody labeling and amplify the signal of the primary antibody. They are the preferred choice for staining low expressing targets and in low-plex assays such as Western blot.
Multi-rAb Recombinant Secondary Antibodies are mixtures of precisely engineered recombinant monoclonal antibodies that recognize multiple complementary epitopes on the same IgG. Each recombinant clone in the final multiclonal secondary mixture is carefully selected after rigorous characterization and screening to ensure the highest level of performance.
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Combines the high sensitivity of polyclonals with the superior specificity of monoclonals
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Unlimited supply, high lot-to-lot consistency, and reproducibility of results throughout your project
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Minimal cross-reactivity with off-target species
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Validated in WB, ELISA, IHC, ICC and Flow Cytometry
Custom Conjugation Services
If your antibody conjugation and labeling needs cannot be met through the options above, Proteintech offers custom conjugation services. We can help with bulk conjugations, ADCs, or even engineer your antibody with AccuBright conjugation sites. Please contact us with your project details for a project proposal and quote.