26 year old AIBN PhD student Will Anderson is two years into his research. We asked him about how his work is progressing and what he hopes to accomplish in his final year.
What is your project?
Single particle analysis in nano/micro-resistive pulse sensing devices.
What does that mean?
My research involves developing technologies that can more easily measure the size, shape, concentration and charge of micro and nanoparticles. Particles in this size range include viruses, vaccines, nanotubes, microvesicles and drug delivery particles and therefore knowing the physical characteristics of these particles is essential as they can determine a particle’s suspension stability, effectiveness and even its toxicity. Unfortunately these measurements can be very time consuming or difficult to make, limiting the insights researchers can make into their particle based systems.
How do you go about your research?
A major focus on my PhD work has been to improve upon the fundamental knowledge in a new class of particle characterization devices, known as a “Tuneable Resistive Pulse Sensors”. This type of sensor has been developed and commercialised by the New Zealand company Izon Science and is being sold as the qNano. This system is capable of individually interrogating single particles, one at a time, to obtain information about their physical properties. Measuring many thousands of particles this way can give a detailed distribution of the different particle characteristics in a sample. We have worked closely with Izon Science to help understand the fundamental physicals behind their tuneable sensors, and this his has allowed us to improve and develop their technology so that it is now capable of measuring individual particles size, charge and (hopefully soon) its shape in a single measurement.
What other lab equipment do you use as part of your research?
I use an array of equipment for particle characterization such as light and electron microscopes and dynamic light scattering devices.
You are involved in a project with an industry partner. Tell us more about that.
It has been very helpful to have a company interested in my research. Izon has been very supportive, providing the major scientific equipment that is integral to my research. Additionally, being able to discuss my findings with their researchers allows me to interpret and understand my results more efficiently. On a professional level I have gained a great deal of insight into how small technology start-ups operate. This experience will be invaluable if I ever decide to pursue an industry or entrepreneurial career.
What stage is your project at now?
As of June 2013 I am two years into my PhD. I would like to finish in the next 12 months as I have dreams of being one of those crazy spectators at the 2014 Tour de France…
Could you tell us more about the 3D imagery you use in your work?
An important part of our research on Tuneable Resistive Pulse Sensors has been the accurate measurement of the geometry of pores used in this system. Pore geometry plays an important role in the sensitivity of particle measurements and also dictates the magnitude of various forces that particles are subjected to as they pass through the pore for analysis. The pores are conical in shape, typically having large openings at ~50 μm and small openings at ~1 μm. To obtain measurements of pore geometry, Trau Group uses optical z-stack microscopy, in combination with software deconvolution, to generate highly detailed 3D images of the pore openings. This method is much faster than conventional confocal microscopy and does not submit the pores to the harsh conditions typical of EM measurements.
What has your research indicated so far?
One of the most exiting discoveries I have been involved in during my PhD was in 2012, when my supervisor Darby Kozak and I, were able to demonstrate for the first time, the single particle size and charge measurements using the Izon qNano system. More recently, I had a paper published that directly compared the ability of Tuneable Resistive Pulse Sensors to size particles against several other methods. The results were promising, indicating that “Tuneable Resistive Pulse Sensors” were equal to, or better than, existing technologies when it came to measuring the size distribution of complex samples, where particles of many different sizes are present.
What is the ultimate outcome of your research? Is it more preventative; diagnostic or treatment-based?
There is a growing field where resistive pulse sensors have been used to detect biomarkers that can indicate disease, such as mutant DNA and abnormal proteins. I hope that the work I am doing in Trau Group will help improve fundamental knowledge of these devices so that diagnostic measurements become simpler and more reliable. Ideally I would hope to see this technology improve to a point where it becomes the ‘go to’ particle analysis platform in biomarker research labs.
What would the holy grail of your research be?
I am very interested in exploiting as much information about a particle as possible with this technology, or similar technology. There is still a great deal of work to be done, however the holy grail would be a completely autonomous device that a researcher could simply squirt a sample into and confidently obtain detailed information about all the particles present.
What problems have you encountered?
My undergraduate degree (Biotechnology) did not have a strong maths background, so one of the biggest challenges to my PhD is the large amount of physics, statistics and programming I have had to learn – or have tried to learn – to fully understand the results we have obtained from our experiments. Fortunately I have been able to get help from some very skilled researchers and students within the AIBN, who have assisted me in these areas when I have been stuck.
If you could change one thing from the time you’ve been doing your PhD, what would it be?
If I were to change anything it would be to not sweat the small stuff, but focus on the aim of the research at hand. By looking at the big picture you stress less and the small fiddly bits will eventually come together on their own.
How does your research fit into the larger workings of the Trau Group lab, the Centre for Biomarker Research and Development?
Every project in our group is linked to at least one other project in some way, whether it’s sharing equipment and expertise, or a major collaboration between two different projects. For example, I will frequently analyse particle suspensions for other members of my group. I am currently collaborating with some other members of Trau Group to use the qNano to detect particles found in blood that have the potential to be effective biomarkers for cancer.
Are you able to collaborate a lot with members of other groups within the AIBN?
Yes. I have worked with other groups to share expertise and equipment many times during my PhD. I have also worked with many of the internal special research groups such as the CMM and the ANFF.
Once you complete your PhD, what do you plan to be the next step in your career?
I haven’t decided what I would like to pursue after my PhD is complete. I think I am going to wait and see if any opportunities present themselves before I make any major decisions about my future.
What was your road to getting to AIBN?
In Trau Group I am the work experience kid who never left. I originally did a semester research project in Trau Group in 2009, after one of my undergrad friends suggested I would enjoy working there. This project involved working with one of the early prototypes of the qNano device I am using now. I came back in 2010 to do honours on a similar project and finally, after briefly working with Izon in Christchurch during the summer of 2010/11, I returned to start my PhD in 2011.
When you one day retire and have a chance to look back at your life, what would you like to say that you’ve accomplished?
I would like to be able to say that I helped advance the field of particle analysis during my PhD. However, as I plan on living much longer after my PhD, hopefully I will also be able to say I did a few other things as well.
Source: AIBN Quarterly