title: Ultra-low fouling and high antibody loading zwitterionic hydrogel coatings for sensing and detection in complex media.
abstract: For surface-based diagnostic devices to achieve reliable biomarker detection in complex media such as blood, preventing nonspecific protein adsorption and incorporating high loading of biorecognition elements are paramount. In this work, a novel method to produce nonfouling zwitterionic hydrogel coatings was developed to achieve these goals. Poly(carboxybetaine acrylamide) (pCBAA) hydrogel thin films (CBHTFs) prepared with a carboxybetaine diacrylamide crosslinker (CBAAX) were coated on gold and silicon dioxide surfaces via a simple spin coating process. The thickness of CBHTFs could be precisely controlled between 15 and 150nm by varying the crosslinker concentration, and the films demonstrated excellent long-term stability. Protein adsorption from undiluted human blood serum onto the CBHTFs was measured with surface plasmon resonance (SPR). Hydrogel thin films greater than 20nm exhibited ultra-low fouling (<5ng/cm(2)). In addition, the CBHTFs were capable of high antibody functionalization for specific biomarker detection without compromising their nonfouling performance. This strategy provides a facile method to modify SPR biosensor chips with an advanced nonfouling material, and can be potentially expanded to a variety of implantable medical devices and diagnostic biosensors.
  
  
  
  In this work, we developed an approach to realize ultra-low fouling and high ligand loading with a highly-crosslinked, purely zwitterionic, carboxybetaine thin film hydrogel (CBHTF) coating platform. The CBHTF on a hydrophilic surface demonstrated long-term stability. By varying the crosslinker content in the spin-coated hydrogel solution, the thickness of CBHTFs could be precisely controlled. Optimized CBHTFs exhibited ultra-low nonspecific protein adsorption below 5ng/cm(2) measured by a surface plasmon resonance (SPR) sensor, and their 3D architecture allowed antibody loading to reach 693ng/cm(2). This strategy provides a facile method to modify SPR biosensor chips with an advanced nonfouling material, and can be potentially expanded to a variety of implantable medical devices and diagnostic biosensors.
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, WA 98195-1750, USA; Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan.
authors.forename: Ying-Nien
authors.initials: YN
authors.lastname: Chou
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, WA 98195-1750, USA.
authors.forename: Fang
authors.initials: F
authors.lastname: Sun
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, WA 98195-1750, USA.
authors.forename: Hsiang-Chieh
authors.initials: HC
authors.lastname: Hung
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, WA 98195-1750, USA.
authors.forename: Priyesh
authors.initials: P
authors.lastname: Jain
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, WA 98195-1750, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Sinclair
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, WA 98195-1750, USA.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, WA 98195-1750, USA.
authors.forename: Tao
authors.initials: T
authors.lastname: Bai
authors.affiliation: R&D Center for Membrane Technology and Department of Chemical Engineering, Chung Yuan Christian University, Chung-Li, Taoyuan 320, Taiwan.
authors.forename: Yung
authors.initials: Y
authors.lastname: Chang
authors.affiliation: Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan. Electronic address: tcwen@mail.ncku.edu.tw.
authors.forename: Ten-Chin
authors.initials: TC
authors.lastname: Wen
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, WA 98195-1750, USA.
authors.forename: Qiuming
authors.initials: Q
authors.lastname: Yu
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, WA 98195-1750, USA. Electronic address: sjiang@uw.edu.
authors.forename: Shaoyi
authors.initials: S
authors.lastname: Jiang
mesh_terms: D000598:Amino Acids, Cyclic / Q000737:chemistry*; D000906:Antibodies / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D003503:Cyclobutanes / Q000737:chemistry*; D006801:Humans; D020100:Hydrogels / Q000737:chemistry*; D008567:Membranes, Artificial
chemical_list: D000598:Amino Acids, Cyclic; D000906:Antibodies; D020099:Coated Materials, Biocompatible; D003503:Cyclobutanes; D020100:Hydrogels; D008567:Membranes, Artificial; C072735:2-amino-1-hydroxycyclobutane-1-acetic acid
keywords: Carboxybetaine; Complex media; Hydrogel coatings; Sensing and diagnostics; Zwitterionic polymers