A bundle of Kevlar fiber

Waite’s body armor stopped the bullet. He and Edwards returned fire and dropped the assailant. Waite was treated at a local hospital for severe bruising – even with body armor, the bullet had the same impact as if someone had slammed him in the chest with a hammer – but he lived to tell the tale.

Waite is one of 2,750 law

While meeting surging war-time demand for the fiber in military body armor in the past two years, the Kevlar team has unveiled an upgraded body-armor product for the U.S. law-enforcement market and introduced anti-terror protections for aircraft such as armored cockpit doors and blast-resistant cargo containers. Meanwhile, on the home front, Spruance has developed an entirely new civilian product -- high-strength panels to guard homeowners against debris hurled by tornadoes.                                          More >>

Cato T. Laurencin, Chair of Orthopaedic Surgery and Professor of Biomedical Engineering and Chemical Engineering at the University of Virginia.

Polymers to Repair the Body

Note: This article is republished by permission of Explorations, a quarterly publication of the University of Virginia office of Research and Graduate Studies.

Dr. Cato Laurencin has been attracted to the versatility of polymers since he first encountered them in a college chemistry class. “At the time, we were just beginning to understand their applications in a biomedical setting,” he recalls. “I thought it was fascinating.” Today, Laurencin, the Lillian T. Pratt

Distinguished Professor and chair of the department of orthopaedic surgery, is leading the effort to use polymers as drug delivery systems and to help regenerate bone, ligament, and tendon tissues.

Laurencin has worked to develop a number of polymers, including the polyphosphazenes and polyanhydrides, that have the advantage of degrading into nontoxic substances that can be readily excreted by the body. “One of the advantages of these polymers is that they degrade in a dependable and reproducible manner in the presence of water,” Laurencin explains. “This makes them particularly advantageous.”

In the 1980s, Laurencin was part of the team that developed a dime-sized polymer wafer to deliver chemotherapy to tumor sites in the brain. It is used to treat glioblastoma multiforme (GBM), one of the deadliest of all cancers. The wafer, impregnated with carmustine, is placed in the cavity left after surgery to remove a GBM tumor, where it dissolves evenly like a bar of soap, discouraging the appearance of new tumors. Its dependable degradation ensures the release of a steady flow of this potent anticancer drug, reducing the danger of overdose. His work has also led to the development of degradable polymer systems that deliver antibiotics locally for the treatment of osteomyelitis, a bone disease.

Laurencin is using biodegradable polymers to create scaffolding that can be used to support bone grafts. Today, the gold standard for bone grafts is bone taken from another part of a patient’s body, but this technique has its limitations. Patients run the risk of inflammation, infection, and chronic pain that occasionally outlasts the pain of the primary surgical procedure. Quantities of bone tissue that can be harvested are limited, creating a supply problem as well.

Laurencin uses a polymer that can be formed into a three-dimensional matrix incorporating tiny microspheres. These microspheres are connected, creating a scaffold along which new bone tissue can grow. These structures can carry bone-forming cells from the patient’s body as well as factors that promote the growth of bone tissue and blood vessels. As new bone is created, the polymer matrix is slowly resorbed by the body.

Laurencin’s research is driven by his firsthand experience as a physician specializing in shoulder and knee surgery. “ My clinical practice serves as the motivator for my work,” he says. “Many of the repairs orthopaedic surgeons perform could be enhanced with engineered tissue.”

Because Laurencin’s work spans a number of disciplines, he was attracted by the University’s eagerness to foster collaborative research. He holds professorships in biomedical engineering and chemical engineering in addition to orthopaedic surgery—and has been named one of only fifteen University Professors, an appointment that entitles him to teach in any school or department.

The Fall Issue of Explorations described other cutting-edge nanotechnology research underway at the University of Virginia. Other articles include:

• To Our Readers
• The Quest for Leadership in Nanotechnology
• A Fluid Approach to Life
• A New Spin on Electronics
• The Complex Ethics of Small Changes
• Designing New Metals
• Next-Generation Catalysts
• Currents in the Blood

Note to readers: Links to these articles are no longer functional.

News

Business

DuPont Engineering Polymers will create 20 new jobs with a major new polymer plant in Chesterfield County . The plant will meet increasing demand for DuPont Zytel HTN high-performance polyamide resins with 30 million pounds per year of capacity. Located adjacent to DuPont’s existing Richmond site in Chesterfield County, the new facility is scheduled for startup by the end of 2004. “The expansion will more than double our base polymer capacity for Zytel HTN,” said Clive Robertson, Global Business Manager for the material. The move supports growing markets for the material in automotive, electronic and other consumer and industrial sectors. “ (Press release, Oct. 20, 2003). More.

Albemarle Corporation has completed its acquisition of Paris-based Atofina S.A.'s bromine fine chemicals business, a unit with annual revenues of over $25 million. Said Albemarle Business Director Joe Tedder: "This acquisition establishes global leadership positions for Albemarle in bromine and bromine fine chemicals, particularly for pharmaceutical and agricultural markets." Albemarle, head-

quartered in Richmond, Virginia, operates two business units, Polymer Chemicals and Fine Chemicals, which generate revenues of $1 billion serving the life sciences market. (Press release, Dec. 2, 2004.)

Airgas, Inc., a distributor of industrial, medical and specialty gases, has dedicated its new liquid carbon dioxide and dry-ice manufacturing plant in Hopewell. The $10 million, world-class facility on the grounds of Honeywell's Hopewell complex began producing liquid carbon dioxide for customers earlier in the year. The production of ammonia at Honeywell’s Caprolactam production site generates a steady, reliable stream of gaseous carbon dioxide that feeds the new Airgas facility. (Press release, Nov. 12). More.

Industrial TurnAround Corporation, a Chester-based construction and engineering firm serving the chemical, film and fibers sector, has announced its merger with Electrical Mechanical Services, Inc., an industrial service company also based in Chester. The combination creates a company with more than 250 professional and field personnel and revenues of $30 million. (Website, October 15, 2003). More. 

Alfa Laval Inc., a global leader in high-

speed separators, and Millipore Corporation, a multinational bioscience company, have announced a joint marketing agreement in the USA for the integration of equipment used for the recovery of biopharmaceutical proteins generated by cell culture and fermentation. Under the agreement, the partnership will promote Alfa Laval’s high-speed biotechnology centrifuges. Alfa Laval USA's corporate offices and Process Technology Division are located in Richmond. (Website, December 2003). More. 

Ethyl Corporation, a Richmond-based producer of chemical additives, has launched its first line of additives created specifically for the metalworking industry. Under the brand name TecGARD, the new line includes emulsifiers, extreme pressure/antiwear agents, corrosion inhibitors, demist additives, quench additives, industrial additives, and lubricity additives. Ethyl contends the chemicals will enhance machine performance in the industry's toughest working environments, from steel mills to aluminum-container fabricators. (Press release, January 6, 2003.)

Albemarle Corp., the world's largest producer of fire retardants, has introduced SAYTEX RX as an alternative to pentaBDE, a widely used retardant being phased out of production. SAYTEX meets the foam manufacturing industry's need for a high-

efficiency flame retardant, offering superior thermal stability and good anti-scorch properties for high- and low-density foams used in furniture, bedding, automobiles and packaging. Albemarle is headquartered in Richmond. (Press release, Nov. 13, 2003.)

The University of Virginia’s School of Engineering and Applied Science has broken ground on Wilsdorf Hall, a building that will bring researchers in materials science, chemical engineering and nanotechnology under one roof. The $39 million, five-story structure will contain research laboratories, faculty offices, conference rooms, computational facilities and work-study areas. Said Dean Richard Miksad: “By bringing together researchers from different disciplines, this building should encourage interdisciplinary research, especially in the field of nanotechnology.” (News story, Sept. 18). More.