scFv (single-chain variable fragment) is the smallest functional antibody fragment, consisting of VH and VL domains connected by a flexible peptide linker.

Size

~25-30 kDa

Valency

Monovalent (1 binding site)

Format

Single polypeptide chain

Production

Bacterial expression

​
Structure

Linker length (typically 15-20 amino acids) is critical for proper folding and stability.
  • VH domain - Variable heavy
  • VL domain - Variable light
  • Flexible linker - Common: (Gly₄Ser)₃

​
Key Applications

Easy library display and selection
Ideal for applications requiring small size and single-gene expression.