Better diagnosis of parasitic infections: rapid, simple enrichment of rare cells by using ultrasound
Parasitic infections like malaria and sleeping sickness affect hundreds of millions of people, primarily in the poorest regions of the world. Diagnosis of these diseases is often difficult because the concentration of parasites in the blood can be very low.
British scientists have now developed a simple chip-based method for enriching rare cells in blood samples. As they report in the journal Angewandte Chemie, this allows the detection limit for the parasites that cause malaria and sleeping sickness to be lowered by two to three orders of magnitude.
Existing techniques for the separation and enrichment of parasites in blood samples are difficult to use in isolated regions and developing countries because they usually require complex chemistry for labeling cells, costly instruments, or extensive infrastructure. An inexpensive technique that requires only small amounts of power, works without labeling the cells, and uses just a drop of blood from a fingertip, is needed.
A team headed by Jonathan M. Cooper at the University of Glasgow has now developed such an approach. Their innovative method is based on an acoustically controlled microchip that is used in a battery-driven, hand-held device. The researchers successfully used their technique to enrich malaria-infected blood cells and the parasite that causes sleeping sickness in blood samples.
The chip contains a special electrode that produces ultrasound when a voltage is applied. If a drop of liquid is placed in a specific location on the device, the form of the acoustic field elicits a particular pattern of flow within the drop: a circular rotational motion.
Particles whose density is lower than that of the liquid are carried against gravity with the upward rising current and transported toward the outer edge of the drop, where they accumulate. In contrast, particles with a higher density collect in the center of the droplet, because they cannot be lifted up.
This works for cells too. Red blood cells infected with the malaria parasite are less dense than non-infected cells. If the density of the drop of blood being examined is adjusted by simply adding a small amount of reagent, the acoustic chip allows the infected red blood cells to be concentrated by a factor of one hundred to one thousand at the outer edge of the blood drop.
The non-infected red blood cells remain at the center of the drop. The method is also suitable for concentrating free-swimming parasites in blood. The researchers were able to enrich trypanosomes, the pathogens that cause sleeping sickness, by using their acoustic chip. Simple staining techniques then make it possible to detect the parasites.
In the future, the technique may be adapted to allow other infectious diseases and rare circulating tumor cells to be detected more readily use of this new technology.
About the Author
Professor Jon Cooper is a Fellow of the Royal Academy of Engineering and holds the Wolfson Chair in Bioengineering at the University of Glasgow. His academic interests include the use of micro- and nanotechnologies for the development of medical diagnostics.
Author: Jonathan M. Cooper, University of Glasgow (UK), http://www.gla.ac.uk/schools/engineering/staff/jonathancooper/
Title: Rare-Cell Enrichment by a Rapid, Label-Free, Ultrasonic Isopycnic Technique for Medical Diagnostics
Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201310401
Jonathan M. Cooper | Angewandte Chemie International Edition
An evolutionary heads-up – The brain size advantage
22.05.2015 | Veterinärmedizinische Universität Wien
Endocrine disrupting chemicals in baby teethers
21.05.2015 | Goethe-Universität Frankfurt am Main
Physicists have developed an innovative method that could enable the efficient use of nanocomponents in electronic circuits. To achieve this, they have developed a layout in which a nanocomponent is connected to two electrical conductors, which uncouple the electrical signal in a highly efficient manner. The scientists at the Department of Physics and the Swiss Nanoscience Institute at the University of Basel have published their results in the scientific journal “Nature Communications” together with their colleagues from ETH Zurich.
Electronic components are becoming smaller and smaller. Components measuring just a few nanometers – the size of around ten atoms – are already being produced...
Development and implementation of an advanced automobile parking navigation platform for parking services
To fulfill the requirements of the industry, PolyU researchers developed the Advanced Automobile Parking Navigation Platform, which includes smart devices,...
The world's first electrical car and passenger ferry powered by batteries has entered service in Norway. The ferry only uses 150 kWh per route, which...
On Tuesday, 19 May 2015 the research icebreaker Polarstern will leave its home port in Bremerhaven, setting a course for the Arctic. Led by Dr Ilka Peeken from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) a team of 53 researchers from 11 countries will investigate the effects of climate change in the Arctic, from the surface ice floes down to the seafloor.
RV Polarstern will enter the sea-ice zone north of Spitsbergen. Covering two shallow regions on their way to deeper waters, the scientists on board will focus...
Nanoengineers at the University of California, San Diego developed a gel filled with toxin-absorbing nanosponges that could lead to an effective treatment for skin and wound infections caused by MRSA (methicillin-resistant Staphylococcus aureus), an antibiotic-resistant bacteria. This "nanosponge-hydrogel" minimized the growth of skin lesions on mice infected with MRSA - without the use of antibiotics. The researchers recently published their findings online in Advanced Materials.
To make the nanosponge-hydrogel, the team mixed nanosponges, which are nanoparticles that absorb dangerous toxins produced by MRSA, E. coli and other...
20.05.2015 | Event News
18.05.2015 | Event News
12.05.2015 | Event News
22.05.2015 | Materials Sciences
22.05.2015 | Information Technology
22.05.2015 | Materials Sciences