Buildup of Polyelectrolyte−Protein Multilayer Assemblies on Gold Electrodes. Role of the Hydrophobic Effect

Abstract

The buildup of layer-by-layer assemblies onto gold surfaces from water-soluble charged polyelectrolytes and proteins is examined using quartz crystal microgravimetry (QCM) and electrochemical techniques. Polyelectrolytes such as poly(styrenesulfonate) and poly(ester sulfonic acid) (Eastman AQ-29D polymer) adsorb spontaneously onto gold, contrary to poly(ethyleneimine). From the modification of the gold surface with a thiol and specific adsorption of polymers under polarization conditions, it is concluded that the hydrophobicity of the gold surface seems to be a determining factor in the adsorption process. Alternate adsorption onto gold resonators first coated with AQ-29D polymer gives stable multilayer films in the case of positively charged lysozyme (pI = 11) or polyheme Desulfovibrio vulgaris Hildenborough cytochrome c3 (pI = 10.5). QCM frequency changes with the number of adsorption steps suggest that a linear increase in film mass occurs. Desulfomicrobium norvegicum polyheme cytochrome c3 (pI = 7), which has a null global charge at neutral pH, is shown to give also stable multilayer AQ-29D/cytochrome c3 films, suggesting that several types of interactions, especially the hydrophobic effect, are involved in the buildup process.

Biohydrogen for a New Generation of H2/O2 Biofuel Cells: A Sustainable Energy Perspective

“…In the 1980s, bioelectrochemistry proved to be a powerful tool with which to link electronic transfer data to the structure and function of low-weight redox proteins. [146][147][148][149][150] Huge redox enzymes incorporate redox cofactors during maturation, where conversion of the substrates takes place. Efficient intramolecular electron transfer is ensured by electron relays over distances of less than 14 , allowing electron tunneling from the active site to the surface of the protein.…”

Crosslink Effect and Albumin Adsorption onto Chitosan/Alginate Multilayered Systems: An in situ QCM‐D Study

“…While a covalent attachment of a protein layer to biomaterials surface can distort their conformation and thereby, reduce or even destroy its biochemical activity, proteins can be physically immobilized with the appropriate orientation of the active sites as a way to maximize accessibility and preserve their structural integrity. [4] Different reports have been conducted concerning the nature of the forces behind polymer/protein assembly, [5] the effect of hydrophilic (OH-terminated) and hydrophobic (CH 3 -terminated) surfaces on the adsorption of bovine serum albumin The adsorption of HSA onto CHI/ALG multilayer assemblies was assessed in situ using QCM-D. It was found that the behavior of HSA on biomaterials surface can be tuned by adjusting parameters of the polyelectrolyte system such as pH, layer number, crosslinker and polymer terminal layer.…”

A survey of the 2001 to 2005 quartz crystal microbalance biosensor literature: applications of acoustic physics to the analysis of biomolecular interactions

“…There are a large number of published papers describing the interaction of proteins and peptides with polymeric and planar thin films (Briseno et al, 2001;Yamashita et al, 2001;Fant et al, 2002;Hibbert et al, 2002;Linder et al, 2002;Park et al, 2002;Takada et al, 2002;Andersson et al, 2002a;Forzani et al, 2003;Hamada et al, 2003;Plunkett et al, 2003;Haynie et al, 2004;Heuberger et al, 2004;Lin et al, 2004;Lojou and Bianco, 2004;Notley et al, 2004;Welle, 2004;Evans-Nguyen and Schoenfisch, 2005). There are a further 55 papers in our database that, whilst involving the interaction of polymer films with protein, have been excluded from this review as they were thought to be of minimal relevance to the readership of this journal.…”

“…ferredoxin) and basic (e.g. cytochrome c3) proteins (Lojou and Bianco, 2003;Lojou and Bianco, 2004). Su et al (2005c) investigated the immobilization of horse radish peroxidase (HRP) on a poly(ethylene-co-acrylic acid) film using QCM-D.…”