title: An in-situ infection detection sensor coating for urinary catheters.
abstract: We describe a novel infection-responsive coating for urinary catheters that provides a clear visual early warning of Proteus mirabilis infection and subsequent blockage. The crystalline biofilms of P. mirabilis can cause serious complications for patients undergoing long-term bladder catheterisation. Healthy urine is around pH 6, bacterial urease increases urine pH leading to the precipitation of calcium and magnesium deposits from the urine, resulting in dense crystalline biofilms on the catheter surface that blocks urine flow. The coating is a dual layered system in which the lower poly(vinyl alcohol) layer contains the self-quenching dye carboxyfluorescein. This is capped by an upper layer of the pH responsive polymer poly(methyl methacrylate-co-methacrylic acid) (Eudragit S100®). Elevation of urinary pH (>pH 7) dissolves the Eudragit layer, releasing the dye to provide a clear visual warning of impending blockage. Evaluation of prototype coatings using a clinically relevant in vitro bladder model system demonstrated that coatings provide up to 12h advanced warning of blockage, and are stable both in the absence of infection, and in the presence of species that do not cause catheter blockage. At the present time, there are no effective methods to control these infections or provide warning of impending catheter blockage.
authors.affiliation: Department of Chemistry, University of Bath, Bath BA2 7AY, UK.
authors.forename: Scarlet
authors.initials: S
authors.lastname: Milo
authors.affiliation: Department of Chemistry, University of Bath, Bath BA2 7AY, UK.
authors.forename: Naing Tun
authors.initials: NT
authors.lastname: Thet
authors.affiliation: Department of Chemistry, University of Bath, Bath BA2 7AY, UK.
authors.forename: Dan
authors.initials: D
authors.lastname: Liu
authors.affiliation: School of Pharmacy and Biomolecular Sciences, University of Brighton, BN2 4GJ, UK.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Nzakizwanayo
authors.affiliation: School of Pharmacy and Biomolecular Sciences, University of Brighton, BN2 4GJ, UK; Queen Victoria Hospital NHS Foundation Trust, East Grinstead RH19 3DZ, UK.
authors.forename: Brian V
authors.initials: BV
authors.lastname: Jones
authors.affiliation: Department of Chemistry, University of Bath, Bath BA2 7AY, UK. Electronic address: a.t.a.jenkins@bath.ac.uk.
authors.forename: A Toby A
authors.initials: ATA
authors.lastname: Jenkins
mesh_terms: D015374:Biosensing Techniques / Q000379:methods; D055499:Catheter-Related Infections / Q000175:diagnosis*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D003692:Delayed-Action Preparations / Q000737:chemistry; D005452:Fluoresceins / Q000008:administration & dosage / Q000032:analysis; D005456:Fluorescent Dyes / Q000008:administration & dosage / Q000032:analysis; D006801:Humans; D020100:Hydrogels / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D011109:Polymethacrylic Acids / Q000737:chemistry; D011512:Proteus Infections / Q000175:diagnosis*; D011513:Proteus mirabilis / Q000302:isolation & purification*; D062885:Urinary Catheters / Q000009:adverse effects*; D014552:Urinary Tract Infections / Q000175:diagnosis*
chemical_list: D020099:Coated Materials, Biocompatible; D003692:Delayed-Action Preparations; D005452:Fluoresceins; D005456:Fluorescent Dyes; D020100:Hydrogels; D011109:Polymethacrylic Acids; C038300:methylmethacrylate-methacrylic acid copolymer; C024098:6-carboxyfluorescein
keywords: Carboxyfluorescein; Catheter-associated urinary tract infections; Hydrogels; Proteus mirabilis; Sensor