An optimized approach for photodynamic inactivation (PDI) and other singlet oxygen applications
Date
2025
Authors
Tieman, Grace M. O.
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Chapter 1 introduces the relevant background information for the basis of the project, including fundamentals on photodynamic inactivation (PDI), photosensitization and photosensitizers, singlet oxygen (1O2), and diazirines. The overall description of the project is provided and how it aims to diminish the knowledge gap.
Chapter 2 provides the proof-of-concept material for this thesis, where a porphyrin is covalently tethered to polyethylene terephthalate (PET) from thermal activation of diazirines. The material is then assessed for its 1O2 production in conjunction with its antimicrobial efficacy, which was a 1.76 log-reduction of Staphylococcus aureus.
Chapter 3 optimizes the light dose and porphyrin loading onto the surface by exploring how 1O2 production was affected by varying the amounts. With the optimized material in hand, it is then assessed for its durability to photobleaching under different light intensities, high (35,000 lx) and ambient (450 lx), for up to two weeks. The results indicate there was only a loss of 1O2 production after 1 week of high intensity exposure.
Chapter 4 provides the synthesis of other porphyrinoid molecules, including corroles, to explore how structure impacts 1O2 generation. The molecules’ 1O2 quantum yield is determined via direct detection methodology. Two of the porphyrins, with the highest quantum yields, are then tested using the solid-state methodology developed in Chapter 2.
Chapter 5 provides a summary of each chapter and subsequently explores potential future directions for the results from this work.
Description
Keywords
Singlet oxygen, Antimicrobial, Photodynamic