The researchers have developed a device that can only be sufficiently described
as an incredible
breakthrough. It may soon revolutionize many aspects of disease
To understand the new device, it is important to grasp how it works.
Many who have suffered through (or enjoyed) an organic chemistry class are
familiar with Nuclear Magnetic Resonance (NMR) imaging machines -- bulky lab
machines designed to detect certain groups of chemicals. It's hard to
imagine an NMR scanner being held in the palm of your hand, but that's
precisely how researchers are approaching the problem.
Nuclear magnetic resonance imaging works by exposing atoms' nuclei to magnetic
fields and then pounding them with radio waves causing them to wobble.
This wobble induces currents in the detector coil, which vary by molecule,
allowing the scanner to detect certain molecular structures. While NMR
scanners are typically found in chemistry labs, they're also commonplace in
resonance imaging (MRI) machines use this phenomena to provide a
non-invasive peek inside people's bodies.
The new handheld device is slightly different from a traditional MRI, in that
it does not produce images. Rather it provides detection of various
molecules. The process starts with the collection of a small fluid
sample, typically blood. The sample is collected using microfluidics
network, which grabs samples of a mere five millionths of a liter (5
microliters) -- some 60 times less than conventional systems.
Hakho Lee, lead author of the research states, "The smaller the system, the
better the sensitivity in terms of absolute amount of sample that can be
The sample is then carried through a series of coils. Inside each of
these coils magnetic nanoparticles, bonded to special detector molecules are
inserted. The detector molecules are designed to bond to molecules on,
say a specific bacteria, or a molecule on the surface of a cancer cell.
Each coil can feature its own separate detection check.
The magnetic nanoparticles make the whole system work, as they are sensitive
even weak magnetic fields from the smaller magnets in a handheld sensor.
This allows for a miniaturized NRM, previously infeasible. Ralph
Weissleder of Harvard Med School and his colleagues devised the new method and
squeezed the electronics for detection onto a chip measuring a mere 2 mm2.
The current prototype features 8 coils and is 800 times more sensitive than
current full-sized medical lab NMRs. In preliminary tests, scientists
were able to identify samples of infectious bacteria with as few as 10
bacteria. They plan to publish additional tests showing that the other 7
coils can be easily tasked with identifying
cancer and diabetes (via blood sugar).
Mr. Lee says the device will revolutionize diagnosis. He states,
"The biggest advantage is that we don't need sample preparation or
purification steps. This method could provide an easy and fast way to
diagnose almost any kind of disease, such as bacterial infection or cancers in
point-of-care settings – right next to the patient or in developing
The device could eventually also be used to analyze water, to aid in public
safety or even to check gaseous samples for airborne pathogens or
pollutants. This could aid in antiterrorism devices by offering rapid
detection of biological or chemical warfare agents.
The new research is generating a great deal of respect and excitement in the
scientific community. Remarks Dusan Uhrin, an NMR spectroscopist at the
University of Edinburgh, "If you came to my lab you would see that our
spectrometers occupy whole rooms, and we are always struggling with sensitivity
in NMR experiments. They have been able to improve the sensitivity such
that they can detect just a few bacteria. It's quite remarkable that they can
detect down to that limit"
The Harvard team hopes to quickly bring the new device to market. Dr.
Weissleder has applied for a patent. He has also founded a new company
named T2 Biosystems to market the product.
DailyTech spoke briefly with T2 Biosystems CEO John McDonough. Mr. McDonough says the product is roughly two years from the mark and will be available in tabletop and handheld versions. He says the key to the product is its ubiquitous nature in that it can test any liquid specimen for virtually anything, anywhere given the proper chemicals.
He states, "T2 is utilizing the science and technology of our founders to develop rapid, accurate and portable diagnostics for nearly any health condition, in nearly any setting. In addition to our advantages of speed to result and ease of use, our miniaturized instrument can accurately identify almost any analyte, including proteins, nucleic acids, or enzymes; bacterial, cancer or other cells; viruses; or small molecule drug compounds within almost any sample, including whole blood, plasma, serum and urine."
If T2 can succeed in this ambitious goal, the future certainly seems bright for this exciting new technology.