title: "Hearing Loss" in QCM Measurement of Protein Adsorption to Protein Resistant Polymer Brush Layers.
abstract: Accurate quantification of nonspecific protein adsorption on biomaterial surfaces is essential for evaluation of their antifouling properties. The quartz crystal microbalance (QCM) is an acoustic sensor widely used for the measurement of protein adsorption. However, although the QCM is highly sensitive, it does have performance limitations when working with surfaces modified with thick viscous layers. In the case of polymer brush surfaces, factors such as the thickness and viscosity of the brush may bring such limitations. In the present work, three types of antifouling molecules were used to explore the applicability of QCM for the evaluation of the protein resistance of hydrophilic polymer brush surfaces. Adsorption was also measured by surface plasmon resonance (SPR) as a reference. It was shown that the detection of adsorbed protein requires that protein be located within a critical distance from the QCM chip surface, determined by the viscosity of polymer brush. For larger proteins like fibrinogen, adsorption is expected to occur mainly "on top" of the polymer brush, and brush thickness determines whether protein is located in the "detectable zone". For smaller proteins like lysozyme, adsorption is expected to occur mainly at the chip surface and within the polymer brush layer and to be detectable by QCM. However, the quantity of adsorbed lysozyme may be underestimated when secondary adsorption also occurred. It is concluded that QCM data suggesting very low protein adsorption on polymer brush surfaces should take account of these considerations and should be treated generally with caution.
authors.affiliation: State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren'ai Road, Suzhou 215123, People's Republic of China.
authors.forename: Yafei
authors.initials: Y
authors.lastname: Luan
authors.affiliation: State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren'ai Road, Suzhou 215123, People's Republic of China.
authors.forename: Dan
authors.initials: D
authors.lastname: Li
authors.affiliation: State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren'ai Road, Suzhou 215123, People's Republic of China.
authors.forename: Ting
authors.initials: T
authors.lastname: Wei
authors.affiliation: State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren'ai Road, Suzhou 215123, People's Republic of China.
authors.forename: Mengmeng
authors.initials: M
authors.lastname: Wang
authors.affiliation: State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren'ai Road, Suzhou 215123, People's Republic of China.
authors.forename: Zengchao
authors.initials: Z
authors.lastname: Tang
authors.affiliation: State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren'ai Road, Suzhou 215123, People's Republic of China.|School of Biomedical Engineering and Department of Chemical Engineering, McMaster University , Hamilton, Ontario, Canada.
authors.forename: John L
authors.initials: JL
authors.lastname: Brash
authors.affiliation: State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren'ai Road, Suzhou 215123, People's Republic of China.
authors.forename: Hong
authors.identifier: 0000-0001-7799-4961
authors.initials: H
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D005340:Fibrinogen / Q000737:chemistry*; D009113:Muramidase / Q000737:chemistry* / Q000378:metabolism; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D058525:Quartz Crystal Microbalance Techniques; D020349:Surface Plasmon Resonance; D013499:Surface Properties; D014783:Viscosity
chemical_list: D011108:Polymers; D005340:Fibrinogen; D009113:Muramidase