The Stevens group uses transformative bioengineering approaches that will overcome severe limitations in current materials in two main areas, namely 1) Biosensing and 2) Regenerative Medicine. A key focus is on understanding and engineering the biomaterial interface using innovative designs and state of the art materials characterisation methods. The Stevens group uses highly multidisciplinary approaches and comprises bioengineers, material scientists, chemists, surgeons and biologists.
Nanomaterials as Diagnostic Platforms
New cost-amenable approaches using innovative designs for nanomaterial-based assays could transform the biosensing field. DNA-, protein- or peptide-functionalised nanoparticle aggregates are particularly useful systems since triggered changes in their aggregation states may be readily monitored. For example, dispersion of gold NP assemblies results in a blue-to-red shift in the visible spectrum. The ability to dynamically assemble and dis-assemble such structures under physiologically accessible environmental conditions, as triggered for example by changes in pH is valuable for the generation of novel tunable and/or switchable materials. Conceptually novel approaches to real-time monitoring of enzyme action using modular peptide functionalized gold NPs and quantum dots are ongoing as is the development of new drug delivery systems. Other innovations of the Stevens group in biosensor design involve both building on their existing highly successful work on plasmonic biosensors and also the design and development of completely new polymersome and fluorescent based biosensors.
Engineering the Cell-Material Interface
Cells are inherently sensitive to local mesoscale, microscale, and nanoscale patterns of chemistry and topography. The Stevens group is developing approaches to control cell behaviour through the nanoscale engineering of materials surfaces including monolayer-protected metal, nanotubes and other nanotopographies/nanochemistries. Far-reaching implications are emerging for applications including medical implants, cell supports, and materials that can be used as instructive three-dimensional environments for tissue regeneration.
Innovative Materials Characterisation of Cells & Tissues
One of the key focuses of the Stevens group is on understanding and engineering the biomaterial interface using state of the art materials characterisation techniques. Raman microspectroscopy shows tremendous promise for the analysis of biological processes within living cells, such as cell cycle dynamics, cell differentiation and cell death. Unlike conventional biological assays, laser-based Raman spectroscopy enables rapid and non-invasive biochemical analysis of cells in the absence of fixatives or labels. The Raman spectrum of a cell is a biochemical 'fingerprint', containing molecular-level information about all biopolymers contained within the cell. The Stevens group is applying live cell Raman spectroscopy and multivariate analytical techniques to study cell differentiation/tissue engineering, heart valve calcification and toxicological studies, whilst they have also developed cutting-edge microscopies for correlative cell imaging.
Bioactive Scaffolds and Tissue Engineering
The goal of regenerating failing organs before the body as a whole is ready to surrender, is now timelier than ever and one in which the design of new bio-inspired materials can play an important role. The Stevens group designs 3-dimensional tissue engineering scaffolds and addresses an important new direction in the engineering of new bio-inspired polymers as tissue engineering materials to promote tissue regeneration. First-in-field biomaterials-based innovations are designed to enable far more effective regeneration of functional tissues, such as bone or heart tissue, which has been notoriously difficult to achieve thus far. These innovations are truly multidisciplinary in nature and will be accelerated towards clinical translation through the numerous clinical, scientific and industrial collaborations established with the Stevens group.