This is a scanning electron microscope image of polystyrene nanoparticles. These particles are roughly 100 nanometers in diameter, and are readily detected with the analyzer. The uniform size distribution is used to calibrate the instrument. Credit: J.L. Fraikin and A.N. Cleland, UCSB |
Precision measurement of
nanoparticles has now become a possibility, thanks to scientists at UC Santa
Barbara.
The UCSB research team has developed a new
instrument capable of detecting individual nanoparticles with diameters as
small as a few tens of nanometers. The study will be published in Nature
Nanotechnology.
“This device opens up a wide range of
potential applications in nanoparticle analysis,” said Jean-Luc Fraikin,
the lead author on the study. “Applications in water analysis,
pharmaceutical development, and other biomedical areas are likely to be
developed using this new technology.” The instrument was developed in the
lab of Andrew Cleland, professor of physics at UCSB, in collaboration with the
group of Erkki Ruoslahti, Distinguished Professor, Sanford-Burnham Medical
Research Institute at UCSB.
Fraikin is presently a postdoctoral associate in
the Marth Lab at the Sanford-Burnham Medical Research Institute’s Center for
Nanomedicine, and in the Soh Lab in the Department of Mechanical Engineering at
UC Santa Barbara.
The device detects the tiny particles, suspended
in fluid, as they flow one by one through the instrument at rates estimated to
be as high as half a million particles per second. Fraikin compares the device
to a nanoscale turnstile, which can count and measure particles as they pass
individually through the electronic “eye” of the instrument.
The instrument measures the volume of each
nanoparticle, allowing for rapid and precise size analysis of complex mixtures.
Additionally, the researchers showed that the instrument could detect bacterial
virus particles, both in saline solution as well as in mouse blood plasma.
In this study, the researchers further discovered a surprisingly high
concentration of nanoparticles present in the native blood plasma. These
particles exhibited an intriguing size distribution, with particle concentration
increasing as the diameter fell to an order of 30 to 40 nm, an as-yet
unexplained result.
