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Adsorption and Desorption of Proteins from Environmentally- and Medically-relevant Surfaces

Hanh Thi My Phan, University of Nebraska - Lincoln


Protein function can be influenced by attachment to surfaces. Understanding of protein adsorption behavior responsible for these functional changes is important for various environmental applications, including prion disease transmission. Infectious prions, a causative agent of prion disease, strongly bind to soil surfaces and medical tools and remain infectious. Studies of prion attachment to soils in the environment and to medical surfaces from the various biologic excreta in which prions are present is limited. To contribute to the knowledge of prion adsorption to surfaces, investigations of different proteins including bovine serum albumin (BSA) and α-synuclein adsorption to a variety of environmentally- and medically- relevant surfaces was conducted using quartz crystal microbalance with dissipation and spectroscopic ellipsometry. Adsorption and desorption of BSA, a model protein, varied as a function of surface properties, BSA concentrations, and pH. The initial adsorption rates, adsorbed layer thickness, and molecule arrangements of BSA adsorbed to the various charged surfaces were strongly dependent on the functional tail groups of the surfaces. α-Synuclein protein, a surrogate for the prion protein, shares many pathologically common traits with prion protein. Understanding the behavior of α-synuclein after binding to environmental surfaces can provide crucial insights into prion conformation and orientation on environmentally- and medically-relevant surfaces. Increased α-synuclein adsorption was observed on the environmental surface compared to the medical surface. α-Synuclein can bind to multiple surface types and decontamination was surface-dependent. Competitive matrices were also found to influence prion adsorption to soil surfaces. Prions were not likely to adsorb to soil in saliva while increased adsorption of prions were observed in the presence of urine or brain homogenate when compared to a buffer solution. Atomic force microscopy images of prion conformation adsorbed to mica, stainless steel, and SiO 2 surfaces were reported. These data provide evidence of the influences of the competitive matrices on prion adsorption to soil surfaces and fundamental information on prion conformational change upon adsorption to environmentally- and medically-relevant surfaces.

Subject Area

Environmental engineering

Recommended Citation

Phan, Hanh Thi My, "Adsorption and Desorption of Proteins from Environmentally- and Medically-relevant Surfaces" (2018). ETD collection for University of Nebraska-Lincoln. AAI10981408.