The Zetasizer Nano particle characterization system from Malvern
Instruments (Malvern, UK) is proving to be an ideal research tool for advanced
healthcare applications such as gene therapy and selective-target carrier molecules.
University of Washington researchers say that accurate zeta potential and particle
size measurements were critical to their successful development of fluorescent,
tumour-targeting iron oxide nanoparticles.
Able to safely cross the blood-brain barrier and selectively illuminate brain
cancer cells during a magnetic resonance imaging (MRI) scan, the innovative
molecules resulting from this research are set to make brain cancer imaging
much safer.
"Safe molecular penetration of the blood-brain barrier depends on a particle's
size, fat content and electric charge. It wasn't until we obtained the Zetasizer
Nano in 2006 that we were able to efficiently measure, monitor and optimise
these properties and develop nanoparticles that deliver the desired half-life
in blood but remain stable long enough to support imaging," explained Professor
Miqin Zhang from the University of Washington's Department of Materials Science
and Engineering.
The blood-brain barrier protects the brain from infection. Current imaging
techniques require the injection of both dyes and a drug to forcefully open
the barrier. Professor Zhang and her team have formulated particles approximately
33 nanometres in diameter. Three times smaller in wet conditions than anything
previously formulated in the lab, these particles can naturally penetrate the
blood-brain barrier without exposing the patient to the risk of infection, and
represent a highly significant advance in brain cancer imaging.
The Nanoparticle Lab within the University of Washington's Department of Materials
Science and Engineering focuses its research on cancer diagnosis and treatment
through imaging enhancement and targeted and controlled therapeutic payload
delivery. This is accomplished by use of nanoconjugates or multifunctional nanovectors.
A nanoconjugate is a chemically modified nanoparticle serving as a "vehicle"
that carries biomolecules to target cells. The term "nanovector" here
refers to a nanosized entity that plays a functional role in the perspective
of therapeutics.
The Zetasizer Nano which plays an integral part in the research work is one
of a series of instruments from Malvern Instruments that delivers particle size
and zeta potential monitoring capabilities at the nanometre scale. Widely used
for characterizing a broad range of nanosized materials from high concentration
colloids through to dilute protein solutions, the Zetasizer range supports the
current trends in frontline scientific research.