TY - JOUR
T1 - Study of adsorption of globular proteins on hydrophobic surfaces
AU - Kao, Ping
AU - Allara, David L.
AU - Tadigadapa, Srinivas
N1 - Funding Information:
Manuscript received February 14, 2011; revised May 11, 2011; accepted May 18, 2011. Date of publication June 09, 2011; date of current version October 21, 2011. This work was supported in part by the National Science Foundation (NSF) under Grant ECCS 0925438, the U.S. Army Research Office under Grant W911NF-07-1-0327, and the NSF-funded PSU Center for Nanoscale Science (MRSEC DMR0080019). This is an expanded paper from the IEEE SENSORS 2010 Conference. The associate editor coordinating the review of this manuscript and approving it for publication was Dr. Thomas Kenny.
PY - 2011
Y1 - 2011
N2 - In this paper, we use micromachined, high-frequency, quartz bulk acoustic wave resonators to systematically study the physical and viscoelastic properties of spontaneously adsorbed globular protein films with molecular weights (MWs) spanning three decades on hydrophobic surfaces. Specifically, changes in the frequency and the Q-factor of the micromachined resonator array were studied as a function of concentration for five proteins, namely human serum albumin (HSA), immunoglobulin G (IgG), human fibrinogen (Fib), alpha-2-macroglobulin (AMG), and immunoglobulin M (IgM) at the fundamental and third resonance modes. The results obtained were interpreted using equivalent electrical impedance models for the multilayer stack on the quartz crystal microbalances surface. Discrete changes in the protein adsorption and the viscoelastic behavior with solution concentration were observed for all the five protein films. The spherical core-shell protein model is used to provide a simple explanation of the results. The work presents the first systematic and quantitative evaluation of the density, thickness, viscosity, and elastic modulus of adsorbed globular protein films and demonstrates the advantages of using micromachined high-frequency bulk acoustic wave resonators for obtaining these types of data.
AB - In this paper, we use micromachined, high-frequency, quartz bulk acoustic wave resonators to systematically study the physical and viscoelastic properties of spontaneously adsorbed globular protein films with molecular weights (MWs) spanning three decades on hydrophobic surfaces. Specifically, changes in the frequency and the Q-factor of the micromachined resonator array were studied as a function of concentration for five proteins, namely human serum albumin (HSA), immunoglobulin G (IgG), human fibrinogen (Fib), alpha-2-macroglobulin (AMG), and immunoglobulin M (IgM) at the fundamental and third resonance modes. The results obtained were interpreted using equivalent electrical impedance models for the multilayer stack on the quartz crystal microbalances surface. Discrete changes in the protein adsorption and the viscoelastic behavior with solution concentration were observed for all the five protein films. The spherical core-shell protein model is used to provide a simple explanation of the results. The work presents the first systematic and quantitative evaluation of the density, thickness, viscosity, and elastic modulus of adsorbed globular protein films and demonstrates the advantages of using micromachined high-frequency bulk acoustic wave resonators for obtaining these types of data.
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U2 - 10.1109/JSEN.2011.2157819
DO - 10.1109/JSEN.2011.2157819
M3 - Article
AN - SCOPUS:80054905585
SN - 1530-437X
VL - 11
SP - 2723
EP - 2731
JO - IEEE Sensors Journal
JF - IEEE Sensors Journal
IS - 11
M1 - 5871999
ER -