Creative Biolabs is the recognized leader in single domain antibody library fields. A wide range of unique services are available, including construction of immunized single domain antibody libraries using llama and camel, construction of synthetic camelised human single domain antibody libraries using DNA synthesis, bio-panning of single domain antibodies libraries and large scale production of recombinant single domain antibodies. 

A single domain antibody (sdAb, also called domain antibody or nanobody) is an antibody fragment consisting of a single monomeric variable antibody domain, and lacking the light chain and CH1 domain of the heavy chain. The first single domain antibodies were engineered from heavy chain antibodies found in camelids (dromedaries, camels, llamas and alpacas); these are called VHH fragments. Cartilaginous fishes (for example sharks) also have heavy chain antibodies (IgNAR, immunoglobulin new antigen receptor), from which single domain antibodies called VNAR fragments are obtained. An alternative approach is to split the dimeric variable domains from common immunoglobulin G (IgG) from humans or mice into monomers by camelising a few key residues.

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