Chelating Surfaces for Native State Proteins Patterning: The Human Serum Albumin Case

The paper reports a new “soft” surface functionalization strategy, based on a highly selective ion metal chelation process. The proposed stepwise methodology implies at first the construction of a monolayer of terpyridine-based thiol (Tpy), whose highly packed structuring has been followed in situ by using quartz crystal microbalance (QCM-D) measurements, showing that the monolayers consist of about 2.7 × 1014 Tpy/cm2. Then, the tridentate sites of the each Tpy moiety are employed to partially chelate divalent metal ions, providing an effective platform to anchoring proteins by completing the metal ion coordination with an available site on the protein of interest. We report the case study of the application of the process to the HSA immobilization onto various surfaces, including Tpy–Fe(II) and Tpy–Cu(II) complexes, as well as hydrophilic bare gold substrates and hydrophobic self-assembled Tpy-based monolayers. It is shown that the chelation interaction between Tpy–Cu(II) complexes and HSA produces the h...