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Membrane proteins are responsible for significant proportion of cellular functions and therefore, implicated in many diseases. For example, more than 60% of therapeutics to date target membrane proteins to alter cellular functions that lead to disease. Recent work has shown that the local membrane environment made up of specific lipids surrounding the protein may be critical in regulating their function. Over the past several decades, supported lipid bilayers (SLB) have emerged as a useful model membrane system to investigate these essential protein functions along with their lipid environment because they can be compatible with wide range of surface-based analytical techniques to quantitatively analyze the biological outcome. However, it is still challenging to capture membrane proteins in functional states along with the native components of the plasma membrane. In this thesis, I proposed a novel strategy to take native cell membrane vesicles budded directly from living cell plasma membranes as intermediates to incorporate the native lipids and proteins into SLB platforms, without suffering from the significant downsides of traditional detergent-based reconstitution. This strategy allows preservation of the complexity of the cell plasma membrane and retention of the natural protein structure and functionality. Another critical advance I introduced to this platform was integration of supporting surface that is a transparent, conductive polymeric material that not only supports the membrane to increase its robustness, but also is capable of reporting protein function as well. These polymeric materials can be tuned so their mechanical property mimics native tissues and these materials are biocompatible with cell membranes, while their cushioning ability mitigates the deleterious interaction from commonly used silica-based surfaces. Due to the merits of the conducting polymer, I developed a biomembrane-based organic electronic device combining the native lipid environment, functional membrane proteins, soft tissue like supporting surfaces, and an electroactive surface that acts as a sensor and reporter. Altogether, with such a device I have demonstrated a variety of biosensing applications including pathogen detection, antibiotic screening, ligand-receptor binding, lipid constituent detection, and, perhaps most significantly, ion channel monitoring. These ion channel receptors are important therapeutic targets for pain management, yet little is understood about how they actually work and furthermore, the role of the membrane in their functions. This new biosensing platform may prove to be a useful new approach for pharmaceutical screening and development, as well as basic science studies of ion channel regulation and biology.

The issue that this thesis addresses is how to integrate Chinese poetry in the teaching of Mandarin in Australian schools. To address this problem, the purpose of this study is to explore which aspects of speaking and writing can be effectively taught with which poetry features to a class of Year 8 non-background beginning L2 learners in an Australian school. To gather data, three cycles of action research were conducted with three features of poetry respectively-repetition, rhyme and rhythm, and grammar, and each cycle lasted for three to nine lessons. The evidences were collected from the researcher’s reflection journals and observation of students, the students’ work samples, test results and focus group interviews, and a mentor teacher’s evaluations and an interview. The data lead to the results that Chinese poetry has efficacy in enhancing L2 learners’ language awareness, reinforcing their memorisation of language content and stimulating their engagement in class activity. Aspects of speaking and writing are identified with the support of poetry, for example, rhyme and rhythm is useful to improve learners’ acquisition of pinyin and phonological awareness. The study may contribute to a new understanding on how to use poetry in L2 classroom in general, and how to use Chinese poetry to effectively teach Mandarin in particular. Also, the identified facilitating and constraining factors in the application of Chinese poetry in Mandarin teaching provide a diversity of teaching strategies.

Emerging technologies to study membrane proteins, protein-lipid interactions, and to create new kinds of sensing and analytical devices, use cell plasma membrane vesicles or ‘blebs’ as an intermediate to form molecularly complete, planar cell surface mimetics that are compatible with a variety of characterization tools and microscopy methods. This approach enables direct incorporation of membrane proteins into supported lipid bilayers without using detergents and reconstitution, preserving the native lipids and other species within the plasma membrane. However, the impact of methods used to induce cell blebbing (vesiculation) on protein and membrane properties is still unknown. This study focuses on characterization of the cell blebs created under various bleb-inducing conditions and its result on protein behavior (orientation, mobility, activity, etc.) and lipid scrambling in this platform. This work enriches our understanding of cell plasma membrane bleb bilayers as a biomimetic platform and represents one of few ways to make molecularly-complete supported bilayers from cell membranes. Such a model system can be widely applied to studies aimed at understanding the roles of membrane proteins as drug targets in drug delivery, in virus-host interactions, and in tissue engineering platforms, among many other bioanalytical and sensing applications. Here, we applied this biomimetic model system to studies of oncogenic micrcrovesicle interaction with stem cell surface. Combined with TIRF, the impact of microenvironment on binding and entry of microvesicle to stem cell surface will be revealed at the single particle level.