QVQ routinely equips single-domain antibodies with a proprietary C-Direct tag at the C-terminus.

This low immunogenic tag allows for good production in yeast, affinity purification, and contains an unpaired thiol for directional conjugation to a wide range of labels.

Possible functionalizations of these sdAbs include genetic fusions and site-directed conjugations via maleimide-thiol reactions to the following molecules.

Alternatively, we offer sdAb-DBCO conjugates for conjugation via Click Chemistry to azide-modified labels including fluorophores of different wavelengths. In addition, we offer custom conjugations to your sdAb and label of interest.

Other functionalizations can be introduced by genetic fusion. QVQ offers the generation of multispecific and multivalent single-domain antibody constructs. In addition, we can fuse single-domain antibodies to different Fc-domains, peptides, or proteins. Other fusion proteins can be generated upon request. Please contact us for more information.