Fluorescence enhanced sensing platform: from UV towards near infrared-ii biological window
File(s)
Author(s)
Fothergill, Sarah
Type
Thesis or dissertation
Abstract
The field of fluorescence is used globally within biosciences, from diagnostic laboratories, research institutes, imaging facilities and in vitro diagnostic companies. One popular application for fluorescence is in fluorescence sensing, such that the intensity of the signal can be correlated with a
disease marker concentration. In clinical practice, these tests could be present in laboratories, with
results used to inform clinicians of the stage of disease or response to treatment, forming a vital tool.
There are multiple formats that this can take, from microarrays printed, to plate-based sensing, to even point of care-based devices. One of the key issues with sensing work, or any fluorescence-based technique, is that there exists a concentration below which no signal can be detected, or the signal
may not be distinguishable from the background noise. This limit of detection is of particular
importance for hard to diagnose diseases, for example some cancers. In the case of hard to diagnose diseases, early and accurate diagnosis of disease is of upmost importance for patient outcomes, allowing for earlier intervention and treatment.
The development of nanotechnology has opened up a realm of new possibilities in multiple fields,
from optics to medicine. Many of the interesting properties of nanomaterials can be attributed to
their quantum properties, namely their behaviour beyond the classical domain. As their physical
dimensions approach the wavelength of light, plasmon resonances occur. In the simplest form, these are vibrations matched between the excitation input source and of the structure’s electron cloud.
Importantly, these resonances can be manipulated advantageously for fluorescence applications, particularly through metal enhanced fluorescence (MEF). MEF states that when the resonance of a metallic nanoparticle matches that of the incoming excitation, and a fluorophore is in close proximity, increased fluorescence may occur.
This thesis explores the potential for nanotechnology-based platforms for fluorescence enhanced
sensing. The focus has particularly been on the generation of scalable, and affordable platforms that could have real world applications beyond the lab. One key concept that is introduced is broadband sensing which extend the applicability of traditional MEF based platforms, making them relevant to a wider variety of fluorophores.
disease marker concentration. In clinical practice, these tests could be present in laboratories, with
results used to inform clinicians of the stage of disease or response to treatment, forming a vital tool.
There are multiple formats that this can take, from microarrays printed, to plate-based sensing, to even point of care-based devices. One of the key issues with sensing work, or any fluorescence-based technique, is that there exists a concentration below which no signal can be detected, or the signal
may not be distinguishable from the background noise. This limit of detection is of particular
importance for hard to diagnose diseases, for example some cancers. In the case of hard to diagnose diseases, early and accurate diagnosis of disease is of upmost importance for patient outcomes, allowing for earlier intervention and treatment.
The development of nanotechnology has opened up a realm of new possibilities in multiple fields,
from optics to medicine. Many of the interesting properties of nanomaterials can be attributed to
their quantum properties, namely their behaviour beyond the classical domain. As their physical
dimensions approach the wavelength of light, plasmon resonances occur. In the simplest form, these are vibrations matched between the excitation input source and of the structure’s electron cloud.
Importantly, these resonances can be manipulated advantageously for fluorescence applications, particularly through metal enhanced fluorescence (MEF). MEF states that when the resonance of a metallic nanoparticle matches that of the incoming excitation, and a fluorophore is in close proximity, increased fluorescence may occur.
This thesis explores the potential for nanotechnology-based platforms for fluorescence enhanced
sensing. The focus has particularly been on the generation of scalable, and affordable platforms that could have real world applications beyond the lab. One key concept that is introduced is broadband sensing which extend the applicability of traditional MEF based platforms, making them relevant to a wider variety of fluorophores.
Version
Open Access
Date Issued
2021-09
Online Publication Date
2024-01-31T00:01:14Z
2024-04-16T15:53:58Z
Date Awarded
2022-02
Copyright Statement
Creative Commons Attribution NonCommercial NoDerivatives Licence
Advisor
Xie, Fang
Sponsor
Engineering and Physical Sciences Research Council
Publisher Department
Materials
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)