Research supports emerging medical device technology
“All sorts of bits and pieces go into people’s bodies,” said Peter Bradley, Ph.D., professor of biology and coordinator of the College’s graduate program in biotechnology. “Metal pins and plates, electrical pacemakers, and plastic joints and bones are just a few of the items routinely used in medical care.”
Last year, Bradley and Orpha James, M.S. ’08—then a biotech graduate student who already held a master’s degree in plastics engineering—conducted research into an area of emerging interest in the medical device field. They tested the biocompatibility of nanomaterials used in the production of thermoplastics designed for medical use. Their research appeared in the July 2009 issue of Convergent Technologies.
James explained that in an effort to enhance the properties of thermoplastic materials for medical devices, scientists are increasingly investigating the use of nanotechnology, a relatively new field of research that focuses on particles smaller than a billionth of an inch. The addition of nanoparticlesto the polymer matrix can enhance the thermal, mechanical, and electrical properties of the polymers. However, the particles must be compatible with both the polymer and the biological systems.
“Research into all types of polymers is ongoing,” James said. “At present there are hardly any nano materials which are biocompatible.”
Bradley and James’s research involved growing cells on plastic embedded with nanoparticles. James supplied the plastic, complements of Foster Corp of Putnam, Connecticut . The Biology Department supplied the cells.
“We have a line of cells that came from the kidney of a Vervet, commonly known as an African Green Monkey,” Bradley explained. “This is a Vero cell line established in Japan in the 1960s. It has the properties of an immortal cell, in that it replicates itself through many cycles of division.” Vero cells, which are stored in an incubator and sustained by a liquid nutrient, are widely used in scientific research.
To test the biocompatibility of various thermoplastics containing nanomaterials, Bradley and James placed Vero cells on plastic sheets and tracked the cells’ growth over a week. All of the plastics used in the study, including polypropylene and nylon, are currently used in the medical industry and are biocompatible. However, the plastics were imbedded with nanoparticles which had not been previously tested for biocompatibility.
Their research showed that the nanoparticles were harmless, but Bradley cautioned that the results of a single study are not conclusive. “The cells multiplied normally and showed no signs of toxicity,” he said. “But much more research needs to be done, and the time when patients will receive implants containing nanoparticles is a long way off.”
Still, their research contributes an important piece of evidence to a field of growing interest. And it demonstrates the strength of the College’s biology and biotechnology programs.
“Tissue culture is very specialized,” said Bradley. “We teach undergrad and graduate students how to do research in this field. And we require each of our graduate students to do a quality research project and report their results in a master’s thesis.”
James describes her experience at WSC as “excellent.” “The College has excellent programs, excellent labs, and is engaged in excellent research,” she said. “I would recommend Worcester State to anyone in a heartbeat,” she said.
Bradley, who teaches tissue culture, is equally enthusiastic about the College’s graduate program in biotechnology. “I like this group,” he said. “Most of the students are professionals. They’re very bright. And since Massachusetts is a leader in biotech initiatives, there is always some fascinating new area of research to pursue.”
Worcester Statement, fall 2009