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arXiv · 1503.02704

Protein Adsorption into Mesopores: A Combination of Electrostatic Interaction, Counterion Release and van der Waals Forces

Sebastian T. Moerz·Patrick Huber
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Abstract

Bovine heart cytochrome c has been immobilized into the mesoporous silica host material SBA-15 in both its native folded and urea-unfolded state. The comparison of the two folding states' behavior casts doubt on the commonly used explanation of cytochrome c adsorption, i.e. the electrostatic interaction model. A detailed investigation of the protein binding as a function of pH and ionic strength of the buffer solution reveals the complex nature of the protein-silica interaction. Electrostatic interaction, van der Waals forces and entropic contributions by counterion release each contribute to adsorption on the silica pore walls.

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Sebastian T. Moerz, Patrick Huber. 2015-03-09. Protein Adsorption into Mesopores: A Combination of Electrostatic Interaction, Counterion Release and van der Waals Forces. https://doi.org/10.1021/la404947j

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