Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Material from shellfish delivers a boost to bioassays and medical tests

18.07.2017

Scientists at the University of Washington have discovered a simple way to raise the accuracy of diagnostic tests for medicine and common assays for laboratory research. By adding polydopamine -- a material that was first isolated from shellfish -- to these tests at a key step, the team could increase the sensitivity of these common bioassays by as many as 100 to 1,000 times.

More sensitive tests would allow scientists to identify pathogens, diseases and specific cellular proteins even when these "biomarkers" are present at levels far below the detection threshold of today's standard tests. Initial results show polydopamine boosted the accuracy and resolution of these tests for biomarkers of HIV, Zika virus and proteins on cancerous tumors.


An artistic rendering of a virus particle (light blue, foreground) bound by brightly-colored reporter molecules in a common laboratory assay.

Credit: Junwei Li/Xiaohu Gao

"Common bioassays are the real workhorses of laboratory experiments and medical tests," said Xiaohu Gao, a UW professor of bioengineering. "By boosting the sensitivity of these tests, we can enable more accurate medical diagnoses earlier in a disease or condition, and enable more certainty and less waste in the research process."

Gao led the team that developed this simple modification for many common medical and laboratory assays. They recently published their approach -- known as enzyme-accelerated signal enhancement, or EASE -- in Nature Biomedical Engineering.

EASE centers on the simple addition of two biochemical components, dopamine and horseradish peroxidase, or HRP, at a key step. HRP is a common protein enzyme used to speed up the rate of reactions in biomedical research. Gao and his team discovered that HRP can connect dopamine molecules together to form the polymer chain polydopamine.

Polydopamine, in turn, accumulates on the surfaces of reaction vessels, such as small Petri dishes. Once the polydopamine is present, scientists can continue the traditional steps of their protocols, but now with a substantially increased test sensitivity. Gao hopes that this simple modification will mean that scientists and medical professionals can easily incorporate EASE into their common practices and procedures.

"Scientists have been trying to improve the accuracy of these common tests for decades, but solutions often involve entirely new protocols or costly pieces of equipment," said Gao. "Understandably, researchers can be reluctant to invest in unfamiliar protocols or expensive new equipment -- but EASE is a simple addition to tried-and-true assays. It's like a software upgrade, instead of changing your operating system."

These assays include some of the most common medical and laboratory tests, such as ELISA, microarrays, FISH and immunohistochemistry imaging. Some of these assays have been used for decades to help hospitals and doctors detect signatures of a disease, ailment or other conditions by looking at a patient's blood, other body fluids or cells. Depending on the test, these telltale signs could be pieces of a bacteria or virus, a chemical, antibodies made by white blood cells, a hormone or even pieces of DNA.

But if these compounds are present at extremely low levels, diagnostic tests can miss them and return inaccurate medical information. By increasing sensitivity, EASE reduces uncertainty and even increases the amount of information these tests can provide. For example, the team used EASE to detect the presence of Zika virus in the placental tissues of primates. But EASE made the assay so sensitive that they were able to see which types of cells within the placenta were infected with Zika, Gao said.

As often happens in research, Gao and his team did not originally set out to solve this problem. Polydopamine was originally isolated from mussels decades ago, and researchers already knew that the substance can react with proteins. But the only protocol they had to form polydopamine necessitated a passive, time-consuming protocol. Lead author Junwei Li, a UW doctoral student in materials science and engineering, was using this approach to coat nanoparticles with polydopamine. But Li noticed that HRP can react with dopamine to form polydopamine, and that this approach is substantially faster than existing methods to make polydopamine.

The scientists don't fully understand why adding polydopamine boosts the sensitivity of these bioassays, and future research could elucidate the mechanism. But Gao's focus is on applying EASE to even more diagnostic tests and diseases.

"EASE has potential to solve real, long-standing problems in research and medical tests," said Gao.

###

UW co-authors are pharmacology doctoral student Madison Baird; research scientists Michael Davis and Wanyi Tai; Larry Zweifel, associate professor of pharmacology and psychiatry and behavioral sciences; Kristina Adams Waldorf, professor of obstetrics and gynecology; Michael Gale, professor of immunology; and Lakshmi Rajagopal, associate professor of pediatrics. An additional co-author is Robert Pierce with the Fred Hutchinson Cancer Research Center. Adams Waldorf is also a faculty member with the Sahlgrenska Academy in Sweden, and Rajagopal is also associate professor at the Seattle Children's Research Institute. The research was funded by the National Institutes of Health, the University of Washington and the Howard Hughes Medical Institute.

For more information, contact Gao at xgao@uw.edu or 206-543-6562.

Grant numbers: R21CA192985, R01AI100989, AI083019, AI104002, AI060389.

Media Contact

James Urton
jurton@uw.edu
206-543-2580

 @UW

http://www.washington.edu/news/ 

James Urton | EurekAlert!

Further reports about: Zika virus dopamine polydopamine proteins shellfish

More articles from Materials Sciences:

nachricht Atomic structure of ultrasound material not what anyone expected
21.02.2018 | North Carolina State University

nachricht Hidden talents: Converting heat into electricity with pencil and paper
20.02.2018 | Helmholtz-Zentrum Berlin für Materialien und Energie

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Stiffness matters

22.02.2018 | Life Sciences

Magnetic field traces gas and dust swirling around supermassive black hole

22.02.2018 | Physics and Astronomy

First evidence of surprising ocean warming around Galápagos corals

22.02.2018 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>