Measurements taken at the molecular scale have for the first time confirmed a key property that could improve our knowledge of how the heart and lungs function.
University of Washington researchers have shown that a favorable electrical property is present in a type of protein found in organs that repeatedly stretch and retract, such as the lungs, heart and arteries. These findings are the first that clearly track this phenomenon, called ferroelectricity, occurring at the molecular level in biological tissues.
The researchers published their findings online June 23 in the Proceedings of the National Academy of Sciences.
“We wanted to bring in different experimental techniques, evidence and theoretical understanding of ferroelectricity in biological functions,” said Jiangyu Li, a UW professor of mechanical engineering and corresponding author of the paper. “We certainly have much more confidence now in the phenomenon itself.”
Ferroelectricity is a response to an electric field in which a molecule switches from having a positive to a negative charge. This switching process in synthetic materials serves as a way to power computer memory chips, display screens and sensors. This property only recently has been discovered in animal tissues and researchers think it may help build and support healthy connective tissues in mammals.
A research team led by Li first discovered ferroelectric properties in biological tissues in 2012, then in 2013 found that glucose can suppress this property in the body’s connective tissues, wherever the protein elastin is present. But while ferroelectricity is a proven entity in synthetic materials and has long been thought to be important in biological functions, its actual existence in biology hasn’t been firmly established.
This study proves that ferroelectric switching happens in the biological protein elastin. When the researchers looked at the base structures within the protein, they saw similar behavior to the unit cells of solid-state materials, where ferroelectricity is well understood.
“When we looked at the smallest structural unit of the biological tissue and how it was organized into a larger protein fiber, we then were able to see similarities to the classic ferroelectric model found in solids,” Li said.
The researchers wanted to establish a more concrete, precise way of verifying ferroelectricity in biological tissues. They used small samples of elastin taken from a pig’s aorta and poled the tissues using an electric field at high temperatures. They then measured the current with the poling field removed and found that the current switched direction when the poling electric field was switched, a sign of ferroelectricity.
They did the same thing at room temperature using a laser as the heat source, and the current also switched directions.
Then, the researchers tested for this behavior on the smallest-possible unit of elastin, called tropoelastin, and again observed the phenomenon. They concluded that this switching property is “intrinsic” to the molecular make-up of elastin.
The next step is to understand the biological and physiological significance of this property, Li said. One hypothesis is that if ferroelectricity helps elastin stay flexible and functional in the body, a lack of it could directly affect the hardening of arteries.
“We may be able to use this as a very sensitive technique to detect the initiation of the hardening process at a very early stage when no other imaging technique will be able to see it,” Li said.
The team also is looking at whether this property plays a role in normal biological functions, perhaps in regulating the growth of tissue.
Co-authors are Pradeep Sharma at the University of Houston, Yanhang Zhang at Boston University, and collaborators at Nanjing University and the Chinese Academy of Sciences.
The research was funded by the National Science Foundation, National Institutes of Health, the National Natural Science Foundation of China and the UW.
For more information, contact Li at firstname.lastname@example.org or 206-543-6226.
Michelle Ma | Eurek Alert!
Discovery of a Key Regulatory Gene in Cardiac Valve Formation
24.05.2017 | Universität Basel
Carcinogenic soot particles from GDI engines
24.05.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.
In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
24.05.2017 | Physics and Astronomy
24.05.2017 | Physics and Astronomy
24.05.2017 | Event News