title: Hydrophilic modification of polystyrene with hydrophobin for time-resolved immunofluorometric assay.
abstract: Herein we reported that a hydrophobin film was used as a solid support on the polystyrene surface for immobilizing antibodies in the time-resolved immunofluorometric assay (TR-IFMA). Quartz crystal microbalance with dissipative monitoring (QCM-D), X-ray photoelectron spectroscopy (XPS) and water contact angle (WCA) measurements, as well as atomic force microscope (AFM) were used to characterize the hydrophilic modification of polystyrene surface with Class I hydrophobin isolated from Grifola frondosa (HGFI). The performance of HGFI-modified polystyrene was evaluated by TR-IFMA of carcinoembryonic antigen (CEA). QCM-D revealed that HGFI formed an intact monolayer on the polystyrene at pH 5. XPS and WCA measurements showed that self-assembling HGFI could render polystyrene surface hydrophilic for three months. AFM indicated that an end-on antibody monolayer was adsorbed on the HGFI film rather than multilayers on the polystyrene in a side-on orientation. Furthermore, a linear calibration curve (from 5 to 600 ng/mL) of CEA showed HGFI-modified polystyrene had higher detection sensitivity than unmodified ones in TR-IFMA. This present method for modifying polystyrene is simple without severe chemical treatment and may have wide applicability to functionalize other supports for immobilizing biomolecules.
authors.affiliation: The Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, No. 94 Weijin Road, Tianjin 300071, PR China.
authors.forename: Zefang
authors.initials: Z
authors.lastname: Wang
authors.forename: Yujian
authors.initials: Y
authors.lastname: Huang
authors.forename: Shan
authors.initials: S
authors.lastname: Li
authors.forename: Haijin
authors.initials: H
authors.lastname: Xu
authors.forename: Markus B
authors.initials: MB
authors.lastname: Linder
authors.forename: Mingqiang
authors.initials: M
authors.lastname: Qiao
mesh_terms: D055910:Antibodies, Immobilized; D002272:Carcinoembryonic Antigen / Q000032:analysis; D015200:Fluoroimmunoassay / Q000379:methods*; D005656:Fungal Proteins / Q000737:chemistry*; D048691:Grifola / Q000737:chemistry; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D018625:Microscopy, Atomic Force; D056951:Photoelectron Spectroscopy; D011137:Polystyrenes / Q000737:chemistry; D058525:Quartz Crystal Microbalance Techniques; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D055910:Antibodies, Immobilized; D002272:Carcinoembryonic Antigen; D005656:Fungal Proteins; D011137:Polystyrenes; D014867:Water