title: Chitosan based substrates for wound infection detection based on increased lysozyme activity.
abstract: There is a strong need of point-of-care diagnostics for early detection of wound infection. In this study, substrates based on functionalized chitosan were developed for visual detection of elevated lysozyme activity, an infection biomarker in wound fluids. For efficient hydrolysis by lysozyme, N-acetyl chitosan with a final degree of acetylation of around 50% was synthesized. N-acetylated chitosan and a chitosan-starch composite were labeled with structurally different dyes resulting in lysozyme-responsive biomaterials. Incubation with lysozyme in buffer and artificial wound fluid lead to a release of colored hydrolysis products already after 2h incubation. Tests in human wound fluid from infected wounds indicated a clear visual color change after 2.5h compared to control samples. A higher degree of swelling of the chitosan/starch containing substrate led to faster hydrolysis by lysozyme. This study demonstrates the potential of the lysozyme-responsive materials for diagnosis of wound infection and provides different diagnostic substrates for potential incorporation in point-of-care devices.
authors.affiliation: Institute of Environmental Biotechnology, University of Natural recources and Life Sciences Vienna, Konrad Lorenz Straße 20, 3430 Tulln an der Donau, Austria. Electronic address: gregor.tegl@boku.ac.at.
authors.forename: Gregor
authors.initials: G
authors.lastname: Tegl
authors.affiliation: Institute of Environmental Biotechnology, University of Natural recources and Life Sciences Vienna, Konrad Lorenz Straße 20, 3430 Tulln an der Donau, Austria. Electronic address: alexandra.rollett@boku.ac.at.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Rollett
authors.affiliation: Institute of Environmental Biotechnology, University of Natural recources and Life Sciences Vienna, Konrad Lorenz Straße 20, 3430 Tulln an der Donau, Austria. Electronic address: jasmin.dopplinger@boku.ac.at.
authors.forename: Jasmin
authors.initials: J
authors.lastname: Dopplinger
authors.affiliation: Qualizyme GmbH, Neue Stiftingtalstrasse 2, 8010 Graz, Austria; ACIB-Austrian Centre of Industrial Biotechnology, Konrad Lorenz Straße 20, 3430 Tulln, Austria. Electronic address: clemens.gamerith@qualizyme.com.
authors.forename: Clemens
authors.initials: C
authors.lastname: Gamerith
authors.affiliation: Institute of Environmental Biotechnology, University of Natural recources and Life Sciences Vienna, Konrad Lorenz Straße 20, 3430 Tulln an der Donau, Austria; ACIB-Austrian Centre of Industrial Biotechnology, Konrad Lorenz Straße 20, 3430 Tulln, Austria. Electronic address: guebitz@boku.ac.at.
authors.forename: Georg M
authors.initials: GM
authors.lastname: Guebitz
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D048271:Chitosan / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis; D009113:Muramidase / Q000378:metabolism*; D013213:Starch; D014946:Wound Infection / Q000175:diagnosis*
chemical_list: D001672:Biocompatible Materials; C012693:N-acetylchitosan; D013213:Starch; D048271:Chitosan; D009113:Muramidase
keywords: Degree of N-acetylation; Diagnostics; Dye; Enzyme responsive; Glucosamine modification; Staining