Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.797987
Title: Photodynamically-active electrospun fibres with selective on-demand antibacterial capability
Author: Contreras, Amy Louise
ISNI:       0000 0004 8506 0335
Awarding Body: University of Leeds
Current Institution: University of Leeds
Date of Award: 2019
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Abstract:
The design of advanced biomaterials is a promising strategy to aid the regeneration of oral soft tissue which can be lost during surgery or disease. Bacterial infection is a common surgery-associated complication which could prevent successful tissue integration. Misuse of antibiotics has led to the concerning spread of antimicrobial resistance (AMR) so alternative antibiotic-free treatments need to be explored. PhotoTherixTM is a product concept based on a bioresorbable electrospun polymer scaffold equipped with antimicrobial photodynamic therapy (aPDT) technology aimed for use in maxillofacial applications. Typically, in aPDT, a photosensitiser (PS) is loaded in its inert form and then activated on-demand through a light source to enable its antibacterial function and this principle is central to the PhotoTherixTM concept. To enable translation to clinical use, this thesis aims to investigate how the scaffold architecture, antimicrobial functionality and selectivity can be controlled via variation of chemical and physical properties of the polymer as well as process electrospinning parameters. Fibrous scaffolds based on Food and Drug Administration (FDA)-approved biodegradable polyesters (poly(e-caprolactone) (PCL) and poly(lactic-coglycolic acid) (PLGA)) were obtained via electrospinning. Electrospinning parameters were investigated to establish defined structure-function relationships. The incorporation and controlled release of two PS (methylene blue and erythrosin B) from the material was studied with regards to scaffold bactericidal effectiveness against two model bacterial strains (Streptococcus mutans and Escherichia coli). Evaluation of the viability of cells populating the scaffold was performed using L929 fibroblasts to determine cell-scaffold relationships. Finally, the selectivity achievable between the bacterial and mammalian cells was determined through in vitro models. The resulting prototype, PhotoTherixTM, could be further developed into a commercial medical device aimed to improve patient outcomes, reduce the health economic burden and control the spread of AMR.
Supervisor: Tronci, Giuseppe ; Raxworthy, Mike ; Wood, Simon Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.797987  DOI: Not available
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