title: Comparison between polyethylene glycol and zwitterionic polymers as antifouling coatings on wearable devices for selective antigen capture from biological tissue.
abstract: Selective capture of disease-related proteins in complex biological fluids and tissues is an important aim in developing sensitive protein biosensors for in vivo applications. Microprojection arrays are biomedical devices whose mechanical and chemical properties can be tuned to allow efficient penetration of skin, coupled with highly selective biomarker capture from the complex biological environment of skin tissue. Herein, the authors describe an improved surface modification strategy to produce amine-modified polycarbonate arrays, followed by the attachment of an antifouling poly(sulfobetaine-methacrylate) (pSBMA) polymer or a linear polyethylene glycol (PEG) polymer of comparative molecular weight and hydrodynamic radius. Using a "grafting to" approach, pSBMA and linear PEG coatings yielded comparative antifouling behavior in single protein solutions, diluted plasma, or when applied to mouse flank skin penetrating into the vascularized dermal tissue. Interestingly, the density of immobilized immunoglobulin G (IgG) or bovine serum albumin protein on pSBMA surfaces was significantly higher than that on the PEG surfaces, while the nonspecific adsorption was comparable for each protein. When incubated in buffer or plasma solutions containing dengue non-structural protein 1 (NS1), anti-NS1-IgG-coated pSBMA surfaces captured significantly more NS1 in comparison to PEG-coated devices. Similarly, when wearable microprojection arrays were applied to the skin of dengue-infected mice using the same coatings, the pSBMA-coated devices showed significantly higher capture efficiency (>2-fold increase in signal) than the PEG-coated substrates, which showed comparative signal when applied to naïve mice. In conclusion, zwitterionic pSBMA polymers (of equivalent hydrodynamic radii to PEG) allowed detection of dengue NS1 disease biomarker in a preclinical model of dengue infection, showing significantly higher signal-to-noise ratio in comparison to the PEG controls. The results of this study will be useful in the future development of a range of protein biosensors designed for use in vivo.
authors.affiliation: Delivery of Drugs and Genes Group (D2G2), Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Queensland 4072, Australia and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, St. Lucia, Queensland 4072, Australia.
authors.forename: Kye J
authors.initials: KJ
authors.lastname: Robinson
authors.affiliation: Delivery of Drugs and Genes Group (D2G2), Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Queensland 4072, Australia and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, St. Lucia, Queensland 4072, Australia.
authors.forename: Jacob W
authors.initials: JW
authors.lastname: Coffey
authors.affiliation: Delivery of Drugs and Genes Group (D2G2), Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Queensland 4072, Australia and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, St. Lucia, Queensland 4072, Australia.
authors.forename: David A
authors.initials: DA
authors.lastname: Muller
authors.affiliation: School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Queensland 4072, Australia; Australian Infectious Diseases Research Centre, St. Lucia, Queensland 4067, Australia; and Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia.
authors.forename: Paul R
authors.initials: PR
authors.lastname: Young
authors.affiliation: Delivery of Drugs and Genes Group (D2G2), Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Queensland 4072, Australia; Australian Infectious Diseases Research Centre, St. Lucia, Queensland 4067, Australia; Faculty of Medicine and Biomedical Sciences, The University of Queensland, St. Lucia, Queensland 4072, Australia; and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, St. Lucia, Queensland 4072, Australia.
authors.forename: Mark A F
authors.initials: MA
authors.lastname: Kendall
authors.affiliation: Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Queensland 4072, Australia; Center for Advanced Imaging, The University of Queensland, St. Lucia, Queensland 4072, Australia; and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, St. Lucia, Queensland 4072, Australia.
authors.forename: Kristofer J
authors.initials: KJ
authors.lastname: Thurecht
authors.affiliation: School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Queensland 4072, Australia.
authors.forename: Lisbeth
authors.initials: L
authors.lastname: Grøndahl
authors.affiliation: Delivery of Drugs and Genes Group (D2G2), Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Queensland 4072, Australia; School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Queensland 4072, Australia; Australian Infectious Diseases Research Centre, St. Lucia, Queensland 4067, Australia; and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, St. Lucia, Queensland 4072, Australia.
authors.forename: Simon R
authors.initials: SR
authors.lastname: Corrie
mesh_terms: D000327:Adsorption; D000818:Animals; D000941:Antigens / Q000378:metabolism*; D000956:Antigens, Viral / Q000032:analysis; D057219:Biofouling / Q000517:prevention & control*; D015374:Biosensing Techniques; D003715:Dengue / Q000175:diagnosis; D004195:Disease Models, Animal; D004864:Equipment and Supplies; D008689:Methacrylates / Q000737:chemistry*; D051379:Mice; D011092:Polyethylene Glycols / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D000941:Antigens; D000956:Antigens, Viral; D008689:Methacrylates; C521589:sulfobetaine methacrylate polymer; D011092:Polyethylene Glycols