Nanobody-Traps are made by coupling recombinant, alpaca-derived single-domain antibody fragments (VHHs) to monovalent matrices (agarose beads or magnetic particles). The result is an invaluable tool for quantitative isolation of fusion proteins and transiently bound factors from various cell extracts and organelles–from all organisms. Designed for use with immunoprecipitation or affinity purification protocols.