Molecular fluorescent and chemiluminescent probes for cancer diagnosis and therapy

• Main Author: Xin, Wei
• Other Authors: Pu Kanyi
• Format: Thesis-Doctor of Philosophy
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Science::Biological sciences; Science::Chemistry
• Online Access: https://hdl.handle.net/10356/164268
• Institution: Nanyang Technological University

Cancer, one of the most threatening diseases facing humanity, is estimated to be responsible for 10 million deaths worldwide in 2022 alone. The most common cancer types for male and female patients include prostate, pancreatic, breast, colorectal, lung, and liver cancer. Many cancers could be averted or prevented if screening or early detection of primary tumors or potential metastases were done in time; more importantly, they significantly minimize the complexity of the therapy regime and could reduce the overall mortality rate. Thus, early cancer detection is critical in diagnosis, intervention, and follow-up treatment. Organic molecular probes, including polymer nanoparticles and small molecular probes, have obtained increasing research interest owing to their diversified and tunable optical properties, multifunctionality, and outstanding biophysical features. In this thesis, three different research works are introduced and discussed. A dye molecule was embedded into the middle of biocompatible polyester; the presence of the long polymer chains on both sides of the fluorophore minimized the aggregation caused quenching effect, producing highly fluorescent colloidal nanoparticles after incorporation with amphipathic surfactant. In addition, we have synthesized a dual-locked activatable phototheranostic probe that can turn on its Near-infrared fluorescence (NIRF) signal for real-time imaging and display different phototherapeutic effects upon response to different biomarkers at different locations of the tumor. This auto-regulated phototherapeutic feature complements the intrinsic drawbacks of a singular therapeutic modality and offers a complete ablation of the tumor with a single excitation source. Moreover, an excitation-free chemiluminescence probe has been chemically modified to have NIRF emission. This modality eliminates the requirement of constant light excitation, which is critical for the fluorescent imaging process, providing a high signal-to-background ratio and enhanced tissue penetration depth.