Nanobody (also called domain antibody or sdAb), is an antibody fragment consisting of a single monomeric variable antibody domain, and lacking the light chain and CH1 domain of the heavy chain. Like a whole antibody, it is able to bind selectively to a specific antigen. With a molecular weight of only 12–15 kDa, nanobody are much smaller than common antibodies (150–160 kDa), and even smaller than Fab fragments (~50 kDa, one light chain and half a heavy chain) and single-chain variable fragments (~25 kDa). The first nanobody were engineered from heavy-chain antibodies found in camelids; these are also called VHH fragments. That's what I leanred from here. Could anyone tell me more about it? What are the advantages? Any answers will be appreciate.