Oriented Protein Immobilization by Chelate Associated Photochemistry
(English)Manuscript (preprint) (Other academic)
We demonstrate herein the synthesis, characterization and application of a novel chelateassociated photochemistry (CAP) for oriented and robust attachment of biomolecular ligandsto sensing surfaces. The chelation agent is nitrilotriacetic acid (NTA) which is capable ofcoordinating two histidine (His) molecules in the presence of Nickel. Therefore a ligandmodified with a His-sequence can be attached to NTA to form an oriented assembly ofligands on the sensor surface. The ligand is then covalently bound to the surface via a nearbyphotolabile benzophenone (BP) which attacks C-H bonds upon UV light activation. Theligand is then available for analyte interaction. The synthesized compounds used in this studyare based on the well-known organosulphur surface chemistry for proper attachment to goldsurfaces. Besides the two BP and NTA alkane thiols/disulphides we also synthesized a fillermolecule with an oligo (ethylene glycol) (OEG) tail to fine tune the surface composition andto reduce non-specific binding. Results from surface plasmon resonance (SPR) measurementsusing a Biacore 3000 instrument indicate that up to 55% larger analyte response is obtainedwith CAP as compared to the response obtained with the random orientation achieved byphotoimmobilization alone.
IdentifiersURN: urn:nbn:se:liu:diva-20647OAI: oai:DiVA.org:liu-20647DiVA: diva2:235434