In the June issue of the journal Biomedical Materials, researchers reported the design and fabrication of a new material to be used for vascular grafts that in the future could ultimately be implanted in patients undergoing coronary artery graft surgery.
A scanning electron micrograph to illustrate the fibrous structure of the tube wall. The fibers are fewer than 500 nanometers in diameter, compared with the average hair shaft, which is 80,000-100,000 nanometers. Photo courtesy of Scott A. Sell/VCU.
The material is a blend of polydioxanone (PDO), a synthetic biodegradable polymer that has been used in suture materials for years, and elastin fibers, used to enhance elasticity and bioactivity of the graft. Elastin, a natural polymer, is also a major component of the arterial wall and is critical to the graft in providing a base for the cells to recognize and interact with the body. Using a technique known as electrospinning, researchers were able to manipulate the PDO-elastin composite into a conduit, or hose, for use as a small diameter vascular graft.
“We have created a vascular graft with a combination of strength and bioactivity – two things we need to maintain and regenerate the graft. Although the body is the best bioreactor for tissue regeneration or wound healing, we hope this new material will be recognized by the body as an environment conducive for regeneration,” said lead author Gary Bowlin, Ph.D., the Harris professor of biomedical engineering in the VCU School of Engineering.
According to Bowlin, the composition of the material reinforces the graft’s mechanical strength, which is critical in order to hold the blood pressure and forces while the regeneration process is taking place. The PDO-elastin blend undergoes slow degradation and causes few adverse reactions compared with previous materials used for the same purpose, he said. The purpose of the new material would be to help a patient regenerate a new artery. If it works as designed the researchers hope that at six months post-surgery, there would be no more synthetic structure left, he said.
“Regeneration needs to be timed just right, and the cells regrowth needs to be strong enough so that the patient’s own artery can take over for the synthetic material and promote regeneration,” Bowlin said. “Additionally, the synthetic material must degrade, because any foreign material in the body for an extended time is susceptible to inflammatory response or even severe infection such as staphylococcus.”
Bowlin and his colleagues are now evaluating how cells respond and interact with the different structures.
For more than 30 years, surgeons have used Teflon as a conduit or “artery” for such operations. Teflon is inert and once implanted in a patient, remains forever. However, this can lead to complications, especially in small diameter grafts in the arms, lower legs and coronary arteries. In addition, synthetic biodegradable polymers that are currently used may be adversely reactive and cause inflammatory responses, which degrades the materials faster and results in poor wound healing.
This work was supported by a grant from the American Heart Association Mid-Atlantic Affiliate.
Bowlin collaborated with Scott A. Sell, B.S.; Michael J. McClure, B.S.; Catherine P. Barnes, M.S.; and Danielle C. Knapp, M.S., all of the VCU School of Engineering’s Division of Biomedical Engineering; David G. Simpson, Ph.D., VCU Department of Anatomy and Neurobiology; and B. H. Walpoth, M.D., who is affiliated with the University Hospital in Geneva, Switzerland.
Sathya Achia-Abraham | EurekAlert!
Biofilm discovery suggests new way to prevent dangerous infections
23.05.2017 | University of Texas at Austin
Another reason to exercise: Burning bone fat -- a key to better bone health
19.05.2017 | University of North Carolina Health Care
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