Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Novel microfluidic HIV test is quick and cheap

19.07.2010
Microfluidic device uses antibodies to 'capture' white blood cells called T cells affected by HIV

UC Davis biomedical engineer Prof. Alexander Revzin has developed a "lab on a chip" device for HIV testing. Revzin's microfluidic device uses antibodies to "capture" white blood cells called T cells that are affected by HIV. In addition to physically binding these cells the test detects the types and levels of inflammatory proteins (cytokines) released by the cells.

Revzin's team collaborated with UCLA electrical engineer Prof. Aydogan Ozcan to integrate an antibody microarray with a lensfree holographic imaging device that takes only seconds to count the number of captured cells and amount of secreted cytokine molecules. The test returns results six to twelve times faster than traditional approaches and tests six parameters simultaneously, based on a small blood sample. The Revzin team published the results of their experiments in the May 2010 issue of Analytical Chemistry.

With further refinements, the test will have wide potential use for multi-parametric blood analysis performed at the point of care in the developing world and resource-poor areas. Its affordability will also make it an attractive option in wealthier areas. Revzin has filed for a patent and is looking for ways to bring his test into clinical use.

"In addition to HIV testing and monitoring, this device will be useful for blood transfusions, where the safety of blood is frequently in question," Revzin says.

The most accurate and effective way to diagnose and monitor HIV infection involves counting two types of T-cells, calculating the ratio between the two types of T-cells, and measuring cytokines. Scientists do this using a method called flow cytometry that requires an expensive machine and several highly trained specialists. Healthcare workers and AIDS activists in the developing world have called for less expensive, more easily performed tests.

"While the point of care field focuses on detection of single parameter (e.g. CD4 counts), we believe that the simplicity of the test need not compromise information content. So, we set out to develop a test that could be simple and inexpensive but would provide several parameters based on a single injection of a small blood volume," explains Revzin.

The HIV test addresses two distinct challenges of blood analysis: 1) capturing the desired cell type from blood, which contains multiple cell types, and 2) connecting the desired blood cell type with secreted cytokines. The test consists of polymer film imprinted with an array of miniature spots. Each spot contains antibodies specific to the two kinds of T-cells (CD4 and CD8) and three types of cytokines printed in the same array. When the blood flowed across the antibody spots, T cells stopped and stuck on the spots.

Each T-cell type was captured next to antibody spots specific for the cytokines they might produce. When antibodies activated the cells, spots adjacent to the cells captured the cytokines they secreted. This connected a specific T-cell subset to its secreted cytokines. The visible color intensity of antibody spots revealed differences in cytokine production by T-cells. Prof. Ozcan's lensfree on-chip imaging allowed the scientists to rapidly image and count T-cell arrays without the use of any lenses or mechanical scanning. Analysis of CD4 and CD8 T-cell numbers, the CD4/CD8 ratio and three secreted cytokines took only seconds.

In the future, Prof. Revzin envisions adding microarrays to the test that can detect proteins from the HIV and hepatitis C viruses.

Lensfree Holographic Imaging of Antibody Microarrays for High-Throughput Detection of Leukocyte Numbers and Function Gulnaz Stybayeva, Onur Mudanyali, Sungkyu Seo, Jaime Silangcruz, Monica Macal, Erlan Ramanculov, Satya Dandekar, Anthony Erlinger, Aydogan Ozcan, and Alexander Revzin Analytical Chemistry, Vol. 82, No. 9, May 1, 2010 3736�.

Holly Ober | EurekAlert!
Further information:
http://www.ucdavis.edu

More articles from Health and Medicine:

nachricht Team discovers how bacteria exploit a chink in the body's armor
20.01.2017 | University of Illinois at Urbana-Champaign

nachricht Rabies viruses reveal wiring in transparent brains
19.01.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>