Microfluidics experts, Dolomite,
have announced that they have now optimised the fabrication of quartz microfluidic
chips, enabling instrument manufacturers to benefit from the many important
qualities of synthetic quartz for use within bioscience and medical systems.
Dolomite is a leader in Microfluidics, a technology also known as ‘lab
on a chip'. This is an exciting new field of science and engineering that enables
very small-scale fluid control and analysis, allowing instrument manufacturers
to develop smaller, more cost-effective and more powerful systems. With lab-on-a-chip
technology, entire complex chemical management and analysis systems are created
in a microfluidic chip and interfaced with, for example, electronic and optical
detection systems.
"The standard material for this technology tends to be glass," said
Gillian Davis. "However, the use of synthetic quartz in microfluidic devices
enables natural fluorescence and detection of a wide variety of compounds, especially
proteins, without labeling. This allows detection of proteins in native conditions,
which is important not only for realizing on-chip CZE separation of proteins,
but also for investigations aimed at protein interactions for diagnostics."
The fabrication processes used to create a microfluidic device have some similarity
to those used in the electronics industry. The channels through which the fluids
flow and interact are etched into materials such as glass or polymers using
similar photolithography processes, for example. The patterned layers are then
very accurately aligned and fused together and drilled to provide microscopic
ports through which the chemicals or gases can enter and leave the device.
The advantages of quartz for microfluidics are due to the facts that it is
hard, chemically inert, UV transparent, non-auto-fluorescent and non-porous
- making it a preferred material for applications in the bioscience sector.
However, much of the challenge of the microfluidic device fabrication in this
material comes from the fact that quartz is much harder than glass. Engineers
at Dolomite have been working for the past year to optimize the fabrication
of quartz devices and they can now etch features with depths of up to 150microns.
This is far deeper than most alternative solutions on the market that can only
offer depths in the region of 20microns. The etching process optimized by Dolomite
ensures that the channels are optically smooth.
"The main issue is that etch times with quartz are very long," said
Gillian Davis. "We have made several important breakthroughs in the manufacturing
process that have helped us optimize the process, it is now realistic for us
to get depths of 50microns in regular production and maybe a maximum of 150microns
for very specific projects."
Dolomite is a leader in this field and won £2m funding from the UK Department
of Trade and Industry's Micro and Nano Technology (MNT) Manufacturing Initiative;
this allowed Dolomite to establish excellent microfabrication facilities that
include cleanrooms, precision glass processing facilities and applications laboratories.
In addition to this, Dolomite has managed to attract top quality engineering
and scientific staff with strong backgrounds across the broad range of disciplines
required for success in bringing microfluidics applications to the market, including
chemistry, biotechnology, control system development, electronics, physics and
instrument design and supply.