Led by Dr Daojing Wang and Dr Peidong Yang, researchers from the Lawrence Berkeley National Laboratory (LBNL) and University of California in the US have developed a multinozzle naonelectrospray emitter which will allow the integration of microfluidic chips that can separate proteins with mass spectrometers.
"Lab-on-a-chip technology has enormous potential for proteomics research, but for this potential to be fully realized, a major advance in interfacing microfluidics with mass spectrometry is needed. Our device provides that interface," said Wang.
According to Dr Wang of the LBNL, the benefits of using microfluidic electrophoresis or chromatography separation techniques include higher throughput, less sample and reagent consumption as well as eliminating cross contamination as the chips could be disposable.
The device, which the researchers have dubbed M3 emitters (microfabricated monolithic multinozzle emitters), will feature in an article in an upcoming issue of Analytical Chemistry.
Proteomics, the study of which proteins are present in cells, how they interact and what they do, has been part of a radical transformation of biological and medical research.
The difference in the abundance of different proteins in different cells has led to the identification of cellular functions and pathways affected by disease as well as providing disease biomarkers.
"Proteomics has become an indispensable tool in biological research, be it diagnostics, therapeutics, bioenergy or stem cell research, and mass spectrometry is proteomics' enabling technology," said Wang.
Indeed, many major suppliers have recently released new mass spectrometers to make this research easier. These include the Synapt from Waters, The LTQ XL from Thermo Fisher Scientific and an updated version of Applied Biosystems/MDS Sciex' 4800 Plus.
Both the Synapt and the LTQ XL use an ionisation method known as electrospray ionisation (ESI) which is one of the most common "soft ionisation" methods that overcomes the tendency of large molecules to fragment.
The technique works by pushing a liquid through a very small, charged capillary and the combining of these to microfluidic systems has, until now, been expensive and troublesome.
According to the authors this is the first time a silicon/silica microfluidic channel has been integrated with a multinozzle nanoelectrospray emiiter.
"This paves the way for the large scale integration of mass spectrometry and lab-on-a-chip analysis in proteomics research," said Wang.
Wang believes that the M3 emitters could be commercialised immediately and the researchers have already filed a patent application.
"We are now in the process of creating a chip that integrates sample processing and preparation as well as detection and analysis," said Wang.
"The ability to perform the full process on a single chip has enormous commercial potential."
