Polypyrrole-coated gold nanoflowers as multifunctional nanoparticles for cancer theranostics
File(s)
Author(s)
Ma, Yun
Type
Thesis
Abstract
Multifunctional nanoparticle platforms for imaging-based cancer diagnostics and tumour therapy garner considerable attraction due to their non-invasiveness and deep tissue penetration. However, those theranostic platforms still suffer from limited spatial resolution, deficient photothermal conversion, and dissatisfied sub-cellular scale mapping. Herein, a multifunctional hybrid core-shell theranostic nanoparticle platform for in-situ cancer imaging-based diagnostics and photothermal therapeutics is reported in this research. This nanoparticle platform leverages the benefits of semiconductive polypyrrole (PPy) as a coating on gold nanoflowers (AuNF) for Raman imaging and near-infrared photoacoustic (PA) imaging. Such a dual-mode imaging system provides a simple yet effective way to guide tumour in-situ photothermal therapy (PTT). By coating PPy on a AuNF, the absorption window is shifted from 680 to 1200 nm, resulting in an enhanced PA imaging intensity across a wide spatial length scale up to the centimetre-level for in vivo detection. Moreover, the potential of subcellular-level 3D Raman imaging for cancer diagnosis is realised by use of a reversible doping-dedoping process of PPy, activated by the acidity of surrounding media. This allows probing the redox state of intracellular microenvironment and thus compensates for the low spatial resolution of PA imaging when applied in in vitro treatments. Meanwhile, the red-shift absorption properties can significantly improve PTT, stemming from increased photothermal efficiency and deep tissue penetration using near-infrared region (NIR) irradiation. These prominent redox-responsive features open new avenues for conductive polymers for accurate, highly efficient, and intelligent theranostics.
Version
Open Access
Date Issued
2023-12-15
Date Awarded
2024-05-01
Copyright Statement
Creative Commons Attribution NonCommercial Licence
License URL
Advisor
Stevens, Molly
Publisher Department
Materials
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)