Biomimetic molecularly imprinted polymers : a new quorum sensing capturing agent to prevent bacterial biofilm formation
department or school: Land and Food Systems, Faculty of
data provider: DSpace
degree campus: UBCV
creator: Ma, Luyao
issued: 2017-04-30T00:00:00
issued: 2016
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: Biofilm is a bacterial community that is responsible for most clinical infections and shows increased resistance to the conventional antimicrobials. Biofilm formation is mediated by quorum sensing (QS), by which bacteria produce and recognize autoinducers (AIs) and thereby coordinate their behaviors in a cell-density dependent manner. The purpose of this thesis project was to design and apply molecularly imprinted polymers (MIPs) to capture AIs, interrupt QS, and subsequently inhibit the formation of bacterial biofilms. Pseudomonas aeruginosa and N-(3-oxododecanoyl)-L-homoserine lactone (3-oxo-C₁₂-AHL) were selected as the bacterial model and target AI molecule, respectively. Photo-initiated bulk polymerization method was conducted to synthesize MIPs using 3-oxo-C₁₂-AHL as the template, itaconic acid (IA) or 2-hydroxyethyl methacrylate (HEMA) as the functional monomer, ethylene glycol dimethacrylate as the crosslinker, 2,2’-azobis(2-methylpropionitrile) as the initiator and N,N-dimethylformamide as the porogen. Different functional monomers and different molar ratios of template: functional monomer: crosslinker were examined to optimize the adsorption capacity and affinity of the synthesized MIPs. Equilibrium rebinding study was conducted to evaluate the adsorption performance of MIPs. MIPs captured 55.2%-61.2% of 3-oxo-C₁₂-AHL in 20% acetonitrile. However, none of them showed good adsorption affinity due to the dominant non-specific binding. In 50% acetonitrile, IA-based MIPs (i.e., 1:6:25 and 1:8:25) demonstrated good adsorption affinity with imprinting factor >1. In biofilm inhibitory studies, P. aeruginosa biofilm was incubated with or without the presence of MIPs for 24 h. Biofilm biomass and sessile cell viability were determined by crystal violet assay and 2,3,5-triphenyl-tetrazolium chloride assay, respectively. Selective HEMA-based polymers (i.e., 1:8:25, 1:6:48 and 1:8:48) significantly (P < 0.05) inhibited the formation of P. aeruginosa biofilms, while al…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/59434
note: BIOMIMETIC MOLECULARLY IMPRINTED POLYMERS: A NEW QUORUM SENSING CAPTURING AGENT TO PREVENT BACTERIAL BIOFILM FORMATION by Luyao Ma B.Sc., Zhejiang University, 2014 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Food Science) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) September 2016 © Luyao Ma, 2016 ii Abstract Biofilm is a bacterial community that is responsible for most clinical infections and shows increased resistance to the conventional antimicrobials. Biofilm formation is mediated by quorum sensing (QS), by which bacteria produce and recognize autoinducers (AIs) and thereby coordinate their behaviors in a cell-density dependent manner. The purpose of this thesis project was to design and apply molecularly imprinted polymers (MIPs) to capture AIs, interrupt QS, and subsequently inhibit the formation of bacterial biofilms. Pseudomonas aeruginosa and N-(3-oxododecanoyl)-L-homoserine lactone (3-oxo-C12-AHL) were selected as the bacterial model and target AI molecule, respectively. Photo-initiated bulk polymerization method was conducted to synthesize MIPs using 3-oxo-C12-AHL as the template, itaconic acid (IA) or 2-hydroxyethyl methacrylate (HEMA) as the functional monomer, ethylene glycol dimethacrylate as the crosslinker, 2,2’-azobis(2-methylpropionitrile) as the initiator and N,N-dimethylformamide as the porogen. Different functional monomers and different molar ratios of template: functional monomer: crosslinker were examined to optimize the adsorption capacity and affinity of the synthesized MIPs. Equilibrium rebinding study was conducted to evaluate the adsorption performance of MIPs. MIPs captured 55.2%-61.2% of 3-oxo-C12-AHL in 20% acetonitrile. However, none of them showed good adsorption affinity due to the dominant non-specific binding. In 50% acetonitrile, IA-based MIPs (i.e., 1:6:25 and 1:8:25) demonstrated good adsorption affinity with imprintin…
has type: Thesis/Dissertation
date issued: 2016-11
is shown at: 10.14288/1.0319091
language: eng
degree discipline: Food Science
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/59434