Electrospinning - Present
Ongoing work continues to extend the methods and results established in my doctoral work. Using the high speed data capture methods in combination with high speed video I am refining the method to estimate flight time in electrospinning. I am working with Electrospinz Ltd. to develop a new polymer supply mechanism that can operate at constant pressure or constant flow rate and report both rates. This work will allow further investigation into the constant charge density in electrospinning systems, providing the potential to use the observation as the basis for automation algorithms in electrospinning.
Since 2012 I have been working on developing electrospun extra-cellular scaffolds using a proprietary method of controlled fibre deposition. This work aims to use a patented method to provide tailored multi-layer cellular scaffolds for the culturing of a wide variety of tissue. The technology to produce these scaffolds would give the opportunity to produce custom material properties and targeted biological signalling throughout the scaffold thickness.
Since 2012 I have been part of an ongoing development effort at Electrospinz Ltd. to produce an image analysis software package for electrospun fibre. I have developed an algorithm for detecting electrospun fibre in electron microscope images that has subsequently led to the development of software package. This software package will soon be released onto the market and will provide researchers with a time efficient method of analysing electrospun fibre.
Since 2011 I have been working on methods to entrap micro polymer beads with surface biological functionality in electrospun membranes for use in filtration, bioreactors and catalysis.
Electrospinning - Past
From 2006 to 2008 I have worked on examining how solution properties and processing parameters affect charge flow in the electrospinning process. This work examined aspects such as electrode substrate, the addition of ionic salt to poly(vinyl alcohol) in water, varying applied voltage and electrode distance to examine the effect on current at the collector, examining fibre diameter changes in response to the above mentioned changes and the use of high speed video to observe the process. This work was funded by a Technology for Industry Fellowship provided by the New Zealand Government and seed funding by Plant and Food Research. This project resulted in three journal papers, one book, one MSc thesis and the formation of Electrospinz Ltd.
From 2008-2009 I worked with replicating the mathematical models of the electrospinning process. This work aimed to reproduce work previously published and examine the feasibility of producing a complete model of the process from initial conditions to final fibre properties. The results of this work demonstrated that the existing models of electrospinning were not able to describe the process in sufficient detail to allow them to be sensitive enough to initial conditions to be used in a predictive capacity. This work was funded by a Technology for Industry Fellowship provided by the New Zealand Government and ongoing funding by Plant and Food Research.
From 2009-2010 I worked on the controlled deposition of electrospun fibre to produce a filter element for the home ventilation system provided by HRV Ltd. This work aimed to produce a terminal filter that would capture ultra-fine particles such as bacterial spores or viruses and kill them. This work resulted in the formation of Revolution Fibres Ltd. and the production of a commercial biodegradable filter element. This work was funded by a Technology for Business Grant provided by the New Zealand Government and ongoing funding by Plant and Food Research.
From 2010 to 2013 I worked with high speed data capture to measure the electric current at both the high voltage electrode and the collector electrode. This work was able to find that the charge density at the Taylor cone in a quasi-stable state was constant. This work was also able to be adapted to provide a method to estimate the flight time of an electrospun jet which has never been able to be done before. The above method was also easily able to test the assumption that the electrospinning process is a closed system and hence charge would be conserved on the jet. The work has found that charge loss is a general part of the electrospinning process. Some of these elements have been integrated into future designs by Electrospinz Ltd. for commercial production machines. This work was funded by a Mechanical Engineering Premiere PhD Scholarship provided by the University of Canterbury and ongoing lab and equipment support by Plant and Food Research and Electrospinz Ltd. This project resulted in two papers and a PhD thesis.