Future projects
For more information on any of these projects below, please contact David Steele
Analysis of osteoblast cell behaviour on nanostructured porous silicon functionalised with chemical gradients of plasma polymerised films
This project involves the development of a high-throughput method for analysing cell response to surface chemistry on nanoporous silicon. Gradients of chemical functional groups will be plasma polymerised onto flat and anodised silicon with controlled pore geometries from < 10 nm to > 100 nm. Following surface characterisation with both XPS and AFM the growth of MG63 osteoblasts on the functionalised nanostructured surfaces will be examined and the effects of both pore size and surface chemistry on cell attachment and spreading studied.
Enhancing nanofiltration processes for retention of organic micropollutants using plasma polymerised nano-coatings
In this project plasma polymerisation techniques will be applied to NF membranes to investigate the possibility of improved retention of MIB and geosmin. Several polymerisation strategies will be trialed using triglyme as the precursor to providing a poly(ethylene glycol) (PEG-like) coating. These plasma polymers have been shown to be resistant to biofouling. The coatings will be prepared then analysed using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Mammalian cell culture techniques will be employed to determine the coating resistance to biofouling. Retention efficiency of the coated NF membranes for MIB and geosmin will be determined using a rapid bench-scale membrane test rig.
Enhancing the attachment of a microcystin-degrading bacterium to sand/silica surfaces
The aim of the proposed project is to study the attachment of microcystin-degrading bacteria onto sand/silica surfaces by evaluating a range of plasma polymer coatings on these surfaces, thereby potentially enhancing the seeding process for biological sand filters. A range of plasma polymer coating on silica surfaces will be prepared and characterised using surface analysis techniques such as SEM and XPS. The well-characterised surfaces will then be evaluated for their ability to attach isolate LH21 initially in simple batch experiments. Molecular methods, such as polymerase chain reaction (PCR), will be utilised in conjunction with other surface characterisation techniques to monitor the attachment. The surface coating which demonstrates the highest affinity for isolate LH21 will then be coated onto sand particles which will ultimately be used in laboratory column experiments to determine the ability of the sand to attach isolate LH21 under plug flow conditions, and to evaluate the ability of the sand column to remove microcystin toxins.
Direct patterning of plasma polymer films onto protein resistant surfaces
The project will use radio-frequency plasma polymerisation to deposit homogeneous protein resistant poly(ethylene glycol) (PEG)-like plasma polymer coatings. The chemistry and topography of these coatings will be characterised by means of X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The protein resistance properties of these coatings will be determined through protein adsorption assays. Micro-plasma jet polymerisation will be used to deposit acrylic acid (AA) plasma polymer films at defined regions onto the PEG-like films. The applicant will then test if proteins are able to adsorb specifically to the AA regions and if the proteins retain their immunological properties.
The influence of heptylamine plasma polymer film loaded with silver nanoparticles surface for 3T3 mouse fibroblast cell growth and determination of proliferation 3T3 fibroblast cell on the surface growth.
Silver, well know as an antimicrobial agent since the ancient Greeks is today widely used in topical gels and impregnated into bandages because of its wide-spectrum antimicrobial activity. Nanoparticles provide a particularly useful platform, demonstrating unique properties with potentially wide-ranging therapeutic applications that include drug delivery, in vivo targeting of tumours and bioimaging. This project will investigate the safe and efficacious use of silver nanoparticles in vitro. Surfaces of a heptylamine plasma polymer, which has proven to support the growth and proliferation of a number of cell types, will be loaded with silver nanoparticles, ranging in both size and concentration.
Characterisation of the fluorescence properties of micro-patterned plasma polymer films
Patterned plasma polymer films are particularly useful in the development of new biomedical devices and can be easily fabricated through physical masking techniques or through direct writing of plasma polymers utilising micro-jet technology. One of the limitations of these films in the development of biomedical devices is that the characterisation of the patterned features usually requires the use of expensive and time consuming surface analytical techniques such as X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry and atomic force microscopy. However, many plasma polymer films also exhibit distinct fluorescence characteristics, which can be used to gain information on the molecular structure of plasma polymer deposit. Therefore, a simpler approach for characterising the patterned features of plasma polymer films, can possibly be accomplished by measuring the fluorescence characteristics of the patterned surface using standard fluorescence microscopy.
In this project, we will prepare plasma polymer films containing different functional groups (including acid, amino and aldehyde groups) under different reaction conditions and analyse the fluorescence properties and surface chemistries of these films to determine a fluorescence finger-print for each plasma polymer deposit. We will then generate patterns of plasma polymer films and determine if the plasma polymer films can be identified according to their fluorescence finger-print.
The Delivery of Bioactive Molecules for Ocular Trauma
Delivering therapeutic compounds into the body in a precisely controlled and targeted manner is an ongoing challenge. Ocular drug delivery is necessary to slow disease progression but is especially difficult due to physiological barriers and the space limitations in and surrounding the eye. Left untreated chronic retinal diseases such as age-related macular degeneration (ARMD), diabetic retinopathy, glaucoma and retinitis pigmentosa can lead to irreversible blindness. Currently available treatment methods include topically and orally administered medications, intraocular injections and surgical intervention.
Intraocular
This discovery project will focus on the use of biodegradable polymer surfaces loaded with biologically active small molecules. A range of techniques including plasma surface engineering and nanotechnology will be employed. Such target molecules include; Bevacizumab, a humanized monoclonal antibody and Ranibizumab, a Fab fragment derived from the same parent molecule as Bevacizumab which are both indicated for the treatment of ARMD; Fluocinolone acetonide (FA) a synthetic hydrocortisone derivative anti-inflammatory indicated for ocular trauma and Ethacrynic acid (ECA) a potential glaucoma drug that can reduce intraocular pressure.
Cornea/Conjunctiva
A parallel project for the surface of the cornea and conjunctiva, utilising similar techniques, will investigate the use of therapeutic soft contact lenses as the delivery vehicle. Target molecules here will include atropine, tetracycline and anti-inflammatory drugs for conditions such as corneal ulcers, trachoma and scleritis.