Fluids behave quite differently at the microscale
and this enables us to do experiments that we would otherwise not be able to do
In the laboratory, at the moment we have 3 focus areas of research
which all have a common requirement for producing spherical capsules
The first is in nuclear fusion energy production
where we need small capsules for putting the nuclear fuel in
The second is where we're making protocells, or artificial cells, for studying membrane-protein interactions
and the third is where we're studying encapsulation of the stem cells to go in the spinal cord
to repair your damaged spinal cord if you've been in a car crash
A microfluidic system can be compared to a large-scale plumbing system, say in this building
but reduced in size, onto a chip
Very small tubes delivering fluids to different types of sensors and other actuators in the system
So we can design small circuits to move around small volumes of fluid
generally using techniques borrowed from the microelectronics industry
Recently, we started using 3D printing to make these microfluidic devices
and that has many benefits because it enables us to make microfluidic devices very rapidly
so we can iterate and make new designs and improve upon those designs very rapidly
It also enables us to make things cheaply
Because these printers are cheap and affordable, it's a technology that we can share with our collaborators
and bring microfluidic technology to other people and other researchers who wouldn't otherwise be using it
Traditional microfluidic techniques require very expensive equipment
and also a great deal of knowledge of how to use that equipment
So that puts a lot of people off
whereas with 3D printing, you just need to be able design it on a computer
which is fairly simple to learn
and then press a button and walk away, and then you come back and your device is ready to use
It's also beneficial that you can incorporate it with more traditional techniques quite easily
you can plug it into existing fittings that are readily available
We begin with the very simple modular building blocks; just tubings and junctions
From there, we expanded that to a wider range of different types of microfluidics
We used those different design systems to make a modular system that's based on Lego
that anyone can print out and click them together and make their own microfluidic systems
Previous researchers have discounted this type of printing because they found that it leaked
and they couldn't see through it
But by refining the print characteristics I found that if you avoid under extrusion
you can make the devices both transparent and water-tight
To avoid under extrusion, you have to print quite thin layers and you have to print quite slowly
So 50-micron layers at speeds of 30 millimeters a second or less
The same techniques that make them water-tight also beneficially make them transparent
because the gaps in between the device are what cause you to lose transparency
We're pleased with what we've been able to achieve with 3D printing for microfluidics so far
but what we're really looking forward to is
as the diversity of the materials with which you can print expands
and the resolution of the printers improves
being able to make not just fluidic circuits, but integrate optical and electronic components also
This will enable us to print multifunctional devices from multiple materials in one single device
We're working with researchers from a range of fields around the world
and 3D printing really allows us to be able to send the design to another laboratory
We're working with people in Italy, for example
and we're able to send them designs that they can print out in their labs
conduct experiments and report back the results the very same day
It really makes the process much simpler so that everyone can access the benefits of microfluidics
The beautiful thing about 3D printing is that potentially everybody can have them
Any other walk of life, a hospital, a biological laboratory, anywhere really - everybody can use them
It democratizes the technology of making things