About event
Modern biomedical research and clinical practice relies on a wide range of materials formed into complex structures to provide suitable environments for cells and tissues. These materials range from metals and glasses to plastics and hydrogels. Constraints on mechanical and optical properties required for particular in-vivo and in-vitro applications are usually not compatible with providing the optimum biological microenvironments for the interfacing cell types.
Here we describe rapid, wet-chemistry free, plasma-based approaches that utilise environmentally-friendly ionised gases to activate a range of materials and structures for spontaneous, reagent-free, covalent functionalisation with bioactive molecules. Molecules that can be immobilised whilst retaining their functions include but are not limited to oligonucleotides, enzymes, peptides, aptamers, cytokines, antibodies, cell-adhesion extra-cellular matrix molecules and histological dyes. Their immobilisation occurs via surface-embedded radicals that are created by energetic ions from the ionised gas bombarding the materials surfaces prior to contact with the biomolecules. Typical time scales of cell cultures necessitate covalent tethering because physical bonding would be susceptible to exchange with biomolecules from the culture media and robust spatial patterning of the molecules is required to replicate physiologically relevant structures.
This presentation will examine the fundamental science and process adaptions that enable such surface modifications to be applied to the internal surfaces of multi-well plates, complex, porous materials and micro/nanostructures whilst retaining favourable optical properties. Strategies to pattern immobilised molecules on the surfaces will be examined. Applications enabling biological studies of the response of individual cells to proteins on a sub-cellular scale, and the preparation of multi-functionalisable nanoparticles will be discussed. The surface embedded radicals are shown to enable polymerisation of hydrogels from thus activated surfaces and control of the density and orientation of surface-immobilised bioactive peptides through pH variations and/or the application of external electric fields during the immobilization.
