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Scheme S1. The synthetic route to prepare PTMM, TTNA, and TTBI. Figure S1 1 H NMR spectrum of PM. Figure S2 1 H NMR spectrum of PTMM. Figure S3 13 C NMR spectrum of PTMM. Figure S4. LC-MS spectrum of PTMM. Figure S5 1 H NMR spectrum of TTA. Figure S6 1 H NMR spectrum of TTNA. Figure S7 13 C NMR spectrum of TTNA. Figure S8. MALDI-TOF-MS spectrum of TTNA. Figure S9 1 H NMR spectrum of TTBI. Figure S10. 13 C NMR spectrum of TTBI. Figure S11. LC-MS spectrum of TTBI. Figure S12. The absorption spectrum of AIEgens in different solvents. Figure S13. PL spectra of AIEgens of AIEgens with different water fractions. Table S1. Comparison of absorption and emission peak between experimental and ML predicted. Table S2. Particle size of AIEgens NPs. Table S3. Zeta potentials of AIEgens NPs. Figure S14. Calculated LUMO and HOMO of PTMM, TTNA, and TTBI. Figure S15. Z-stack images of phantom of PTMM NPs. Figure S16. Z-stack images of phantom of TTNA NPs. Figure S17. Z-stack images of phantom of TTBI NPs. Figure S18. Experimental and predicted data are compared using 10-fold cross-validation. Figure S19. ML prediction error distribution. Figure S20. Model scalability. Figure S21. Comparison of ML accuracy and TD-DFT. Figure S22. Illustration of 10-fold cross-validation.

Superposition of a Bessel beam with another beam was usually achieved using an Axicon or a SLM. Here we demonstrate a straightforward but powerful method to superpose a Bessel beam with another Bessel beam or a Gaussian beam based on a Digital Mirror Device (DMD). Different ring or circular patterns could be loaded in the DMD to generate Bessel beams or Gaussian beams respectively. By combining the ring and circular patterns, superposition of a Bessel beam with other Bessel beams or Gaussian beams could be achieved without using beam splitting or other complicated optical setups. The new DMD based Bessel beam superposition method could be easily controlled, quickly switched, or conveniently packed.

We have developed aggregation-induced emission (AIE) dye loaded polymer nanoparticles with deep-red emission for siRNA delivery to pancreatic cancer cells. Two US Food and Drug Administration (FDA) approved surfactant polymers, Pluronics F127 and PEGylated phospholipid, were used to prepare the dye-loaded nanoparticle formulations and they can be used as nanovectors for gene silencing of mutant K-ras in pancreatic cancer cells. The successful transfection of siRNA by the developed nanovectors was confirmed by the fluorescent imaging and quantified through flow cytometry. Quantitative real time polymerase chain reaction (PCR) indicates that the expression of the mutant K-ras oncogene from the MiaPaCa-2 pancreatic cancer cells has been successfully suppressed. More importantly, our in vivo toxicity study has revealed that both the nanoparticle formulations are highly biocompatible in BALC/c mice. Overall, our results suggest that the AIE dye-loaded polymer nanoparticle formulations developed here are suitable for gene delivery and have high potential applications in translational medicine research.

In the last two decades, quantum dots (QDs) have demonstrated great potential for biophotonics applications such as optical imaging and analytes sensing. For these purposes, cadmium-based (Cd-based) QDs are most commonly used because of their excellent optical properties, while cadmium-free (Cd-free) QDs are attracting increasing attention due to the low toxicity of their components. Generally, for use in biological fluids, QDs are either prepared using the aqueous synthesis method or the hot colloidal synthesis method followed by a phase transfer process. This thesis studies the preparation of water-dispersible Cd-based and Cd-free QD by using these two methods and explores their potential for biophotonics applications. First, this thesis presents a facile aqueous synthesis method for preparing the biofunctionalized Cd-based QDs. The CdTe QD nanocrystals were fabricated in a microfluidic chip by using protein molecules as coordination ligands. Compared to the conventional bench-top method, the microfluidic synthesis approach produced the CdTe QDs with enhanced stability and improved biofunctionalization efficiency. Another method of preparing the aqueous QDs, phase transfer of the QDs synthesized in organic solvents, was also examined. Hydrophilic ligands with different chain lengths and functional groups were applied to render the QDs water-dispersible by using the ligand exchange method. Each set of QDs capped with specific surface ligands displayed strengths and limitations in certain aspects of their physicochemical properties, and induced different cellular responses. To mitigate toxicity concerns in biophotonics applications, Zn-Cu-In-S QDs, which are quaternary and Cd-free QDs, were prepared using a facile aqueous synthesis method. The composition effect on their optical properties is demonstrated and correlated with the evolution of their structure and energy band gap. Using the same strategy of composition control, Zn-Ag-In-S QDs with different emission wavelengths were synthesized in the organic phase and then transferred into the aqueous phase via the encapsulation method. The resulting water-dispersible ZAIS QDs exhibited bright photoluminescence and long fluorescence lifetime and were applied in temporally multiplexed imaging of cells. Finally, ZnO QDs, a type of Cd-free QDs made from wide-band-gap oxides, were prepared using the sol-gel method. Their optical properties were modified via chemical doping and photodoping techniques. Their redox-sensitive photoluminescence and plasmonic properties make them promising candidates for biosensing applications. In summary, this thesis covers the manipulation of optical properties, surface chemistry and biocompatibility of Cd-based and Cd-free QDs using versatile strategies in synthesis and surface modification processes, and demonstrates the potential of using these QDs in biophotonics applications. Doctor of Philosophy (EEE)

Individualised medicine, which aims to comprehensively optimise diagnostic and therapeutic strategies for individual patients, has been greatly advanced by the recent development of novel devices based on micro-electro-mechanical system (MEMS) technology. This dissertation presents two approaches that make use of microfluidics & MEMS technology for design, fabricate and test lab-on-a-chip devices intended to provide individualised medicine. The first approach is an implantable drug delivery device for localized administration of chemotherapy. The device enables the efficient and controllable delivery of chemotherapeutic drugs to tumors to enable the reduction of side effects during treatment. The device was tested using cancer cells and animal models to evaluate its reliability and safety for clinical use. In the second approach, we developed two prototypes of lab-on-a-chip platform for cancer drug screening and testing. Its low cost, ease of use and flexibility were designed to meet the requirements of individualised medicine. Using this platform, we demonstrated drug testing on cultured cells and multicellular spheroids to investigate novel cancer drugs. DOCTOR OF PHILOSOPHY (EEE)