A label-free immunosensor array using single-chain antibody fragments

作者：Backmann N; Zahnd C; Huber F; Bietsch A; Pluckthun A; Lang HP; Guntherodt HJ; Hegner M^*; Gerber C

来源：Proceedings of the National Academy of Sciences of the United States of America, 2005, 102(41): 14587-14592.

DOI：10.1073/pnas.0504917102

• cantilever arrays
• nanomechanics
• proteomics

We report a microcantilever-based immunosensor operated in static deflection mode with a performance comparable with surface plasmon resonance, using single-chain Fv (scFv) antibody fragments as receptor molecules. As a model system scFv fragments with specificity to two different antigens were applied. We introduced a cysteine residue at the C terminus of each scFv construct to allow covalent attachment to gold-coated sensor interfaces in directed orientation. Application of an array enabled simultaneous deflection measurements of sensing and reference cantilevers. The differential deflection signal revealed specific antigen binding and was proportional to the antigen concentration in solution. Using small, oriented scFv fragments as receptor molecules we increased the sensitivity of microcantilevers to approximate to 1 nM.

• 出版日期2005-10-11