Ni(II)-modified solid substrates as a platform to adsorb His-tag proteins

LAURA E. VALENTI; VITOR MARTINS; ELISA HERRERA; ROBERTO M. TORRESI; CARLA E. GIACOMELLI

Journal of Materials Chemistry B

RSC

Año: 2013 vol. 1 p. 4921 - 4921

2050-750X

his work investigated a simple and versatile modification to a solid substrate to develop electrochemical bio-recognition platforms based on bio-affinity interactions between histidine (His)-tagged proteins and Ni(II) surface sites. Carboxylate (COO)-functionalized substrates were prepared in multiple steps, initiated with an amino-terminated self-assembled monolayer (SAM) on polycrystalline gold. Surface enhanced Raman spectroscopy (SERS), quartz crystal microbalance with dissipation monitoring (QCM-D) and contact angle measurements were used to follow the modification process. Upon completion of the modification process, the surface COO?Ni(II) chelate complex and the coordination mode used to bind the His-tag proteins were characterized by X-ray absorption near-edge spectroscopy (XANES). Finally, the electrochemical stability and response of the modified substrates were evaluated. The versatility of the modification process was verified using silica as the substrate. QCM-D and S