BBI Contributing Editor
SYDNEY, Australia The 7th World Biomaterials Congress, hosted by the Australian Society for Biomaterials (Brunswick Lower, Australia), provided a showcase of biomaterials technology in Sydney's Darling Harbour sector, with nearly 2,000 scientists in attendance from 43 countries delivering 2,052 oral or poster presentations. Biomaterials has become one of the most interdisciplinary sciences, as seen in the wide range of applications, such as drug eluting devices, nanocoating technologies and tissue engineering, for use across the full range of medical products.
Commonwealth Scientific and Industrial Research Organization (CSIRO; Dickson, Australia) is Australia's premier life sciences research organization. In its 76-year history, CSIRO has formed strategic alliances with governments, industries and businesses in 80 countries. Its work in biomaterials includes biocompatible polymers and coatings for ophthalmic, orthopedic, tissue engineering and dental applications.
CSIRO's Division of Molecular Science developed the Focus Night and Day extended-wear contact lens for CIBA Vision (Duluth, Georgia), a subsidiary of Novartis (Basel, Switzerland). The organization also is seeking a partner for an implantable contact lens being developed at the Cooperative Research Center at the University of New South Wales (Sydney, Australia) and was described by Professor Brien Holden in a presentation on ophthalmic biomaterials.
CSIRO also has developed Elast-Eon, a biostable silicone-polyurethane copolymer, which was acquired by AorTech Biomaterials Pty (Mulgrave, Australia) and is being evaluated for use in a revascularization graft by Percardia (Merrimack, New Hampshire), as a frame in a heart valve by an undisclosed medical device company, as a spinal disc by several leading orthopedic companies and for use in interventional cardiology products by Abbott Laboratories (Abbott Park, Illinois).
Xceed Biotechnology Ltd. (Perth, Australia) has invested in CSIRO's biodegradable polymer platform technology, the core of a newly formed company, PolymerCo Pty (Melbourne, Australia), which seeks to develop applications for these materials in orthopedics, orthodontics, drug delivery, cartilage repair and wound care.
CSIRO also is partnering with the Industrial and Technical Research Institute of Taiwan in the development of a urethane-based biodegradable polymer for cartilage repair and is collaborating with the University of Adelaide (Adelaide, Australia) in the development of a biological adhesive that is based on a compound isolated from an Australian frog.
Additional development programs at CSIRO include an artificial ligament based on a combination of collagen and a synthetic polymer, and a urethane prepolymer system that can be cured to form a biodegradable polymer for use as a bone substitute.
A new initiative within CSIRO is a program called Future Materials, which is funded by the Australian government to provide consultants to act as intermediaries for small companies (fewer than 100 employees) and assist in their collaboration with universities and with other companies. An example is a tapered and threaded hip implant from Portland Orthopaedics (Mattraville, Australia) that can be screwed into the femur. Some 540,000 hip replacements are performed annually worldwide. To prevent loosening of the implant, CSIRO commenced development at Monash University (Melbourne, Australia) of a plasma-sprayed coating of hydroxyapatite, a substance that enhances bone in-growth and better anchoring of the implant.
In another case, Polartechnics (Sydney, Australia) developed Truscan, a simple and reliable test as an alternative to the Pap smear for detecting cervical cancer, of which there are 370,000 new cases worldwide each year. Truscan utilizes both optical and electrical measurements of the cervical tissue taken by electrodes. During manufacturing, some batches of electrodes suffered loss of capacitance. Using X-ray photoelectron spectroscopy for surface elemental analysis at the Future Materials' facility at the University of New South Wales (Sydney, Australia), it was found that minute quantities of indium and copper contaminants introduced during the sputtering process were the cause of the electrode failures.
Elastagen Pty (Sydney, Australia) is a new company that has demonstrated the ability to produce elastic cellular matrices, based on research conducted over 10 years by professor Tony Weiss at the University of Sydney. Elastin is a major elastic component of tissues and organs and provides a scaffold for tissue engineering and regenerative medicine. However, elastin is currently lacking in tissue-engineered grafts. The company has produced gram-scale quantities of recombinant human elastin protein, tropoelastin, which was described in its poster presentation as being critically lacking in tissue-engineered grafts. Tropoelastin was cross-linked to form a synthetic elastin that acts as a hydrogel onto which cultured cells grow.
Spire Biomedical, a subsidiary of Spire Corp. (Bedford, Massachusetts), recently introduced Decathlon, the third entry in its line of split-tip, high-flow catheters for use by dialysis patients. These catheters utilize Spire's core competencies in surface engineering. They are distributed outside the U.S. by Gambro Renal Products AB, a subsidiary of Gambro AB (Lund, Sweden).
A new initiative at Spire is its biophotonics lifesciences program, aimed at developing optoelectronic components for use in biophotonic instruments such as a fiber, laser-based surgical systems for treating glaucoma in a program sponsored by the National Institutes of Health (NIH; Bethesda, Maryland), for ear myrinogotomy and in an instrument for noninvasive blood glucose monitoring. The Centers for Disease Control and Prevention (CDC; Atlanta, Georgia) is funding Spire's development of a portable optical instrument for plague detection.
Spire also has launched research and development programs in nanotechnology and has a grant from the NIH to explore nanostructured coatings for orthopedic implants and a grant from the National Science Foundation (Arlington, Virginia) for investigating the use of a biocompatible nanostructured semiconductor as a smart neural scaffold and nerve guide.
SurModics (Eden Prairie, Minnesota), known for its work on the drug eluting Cypher coronary stent sold by Cordis, a subsidiary of Johnson & Johnson (New Brunswick, New Jersey), is collaborating with the Doheny Eye Institute, an affiliate of the University of Southern California (Los Angeles, California), in the development of a drug eluting coating on an implanted ophthalmic coil for treating retinal diseases including macular degeneration and diabetic retinopathy. The product will be marketed by InnoRx (Mobile, Alabama).
SurModics also is working with Novacell (Irvine, California) on encapsulated pancreatic islet cells which is in animal trials and is expected to enter human trials later this year.
Hyaluron (Burlington, Massachusetts), a contract manufacturer and marketer of hyaluronic acid and its derivatives, produces an injectable formulation of sodium hyaluronate for treating osteoarthritis of the knee. It is sold in Europe by Hexal AG (Holzkirshen, Germany) and is similar to Orthovisc from Anika Therapeutics (Woburn, Massachusetts), which is sold by Johnson & Johnson's Ortho Biotech (Bridgewater, New Jersey) unit, and Synvisc from Genzyme (Cambridge, Massachusetts).
Hemoteq (Wuerselen, Germany) was founded by researchers on hemocompatible biomembranes at the nearby Polytechnic University (Aachen, Germany). It provides customized surface modifications of medical devices and featured at the biomaterials congress its nanocoating technology, which enables the deposition of a covalently bound single molecular layer of a biomaterial on a wide range of substrates, including metals and alloys, polymers and plastics, ceramics and glass.
The company's Camouflage thrombo-protective and biomimetic coating is a covalently bonded synthetic carbohydrate. Its Repulsion antirestenotic coating is biodegradable and hemocompatible to prevent platelet aggregation and clot formation and long-term patency. Ouverture is Hemoteq's proprietary combination of the above coatings and is intended for use in drug-eluting stents. Its Lubriteq coatings are used to provide lubricity. Hemoteq is working on interventional cardiology products with U.S. companies.
Scandinavian Micro Biodevices (SMB; Farum, Denmark), a subsidiary of Inverness Medical Innovations (Waltham, Massachusetts), combines microfluidics and surface modification for use in biochips in diagnostic products. It is used to produce SMB's SpotOn and SoftPlasma DNA microarray slides. SMB's -Surface patented plasma surface modification technology can be used to deposit polymeric thin films onto a wide range of substrates to impart biological properties, such as hydrophilic/hydrophobic and cytophilic/cytophobic surfaces. SMB develops and manufactures customized surfaces on a contract basis. The coating process entails placing a material in a vacuum chamber where a plasma field is created and into which a monomer is introduced, leading to polymerization of the monomer onto the material's surface.
Invibio (Greenville, South Carolina), a subsidiary of Victrex (Lancashire, UK), recently received the CE mark for use of its Peek-Optima thermoplastic polymer in a dental implant. The polymer is sold by Icotec (Altst tten, Switzerland) for use in a continuous carbon fiber that is fabricated into orthopedic pins and plates. The company is developing a bioactive grade of Peek-Optima by combining it with hydroxyapatite for use in dental implants. Peek-Optima has good resistance to gamma, steam and ethylene oxide sterilization methods as well as resistance to commonly used solvents and cleaning agents.
NovaMatrix (Oslo, Norway), a subsidiary of FMC (Philadelphia, Pennsylvania), is a supplier of chitosan, hyaluronic acid and alginates. Its Protasan ultrapure chitosan is used as a scaffold in wound dressings. It is being developed for use in a nasal drug delivery system because of its cationic and bioadhesive properties that increase the transport of polar drugs across epithelial surfaces. The company's Pronova sodium alginate is used as a bulking agent to prevent bladder reflux.
For most applications, alginate microbeads are used because of their high surface to volume ratio. Alginate microbeads are being evaluated as a protective barrier by immobilizing living cells that can excrete therapeutic products for the treatment of cancer and diabetes. NovaMatrix, in collaboration with the Animal Health Trust in the UK, is evaluating the use of alginate entrapped cells that release endostatin, an angiogenesis inhibitor, for the treatment of brain cancer, alginate microbeads containing Factor VIII for the treatment of hemophilia and, in collaboration with the NIH, alginate encapsulated cells that release l-dopamine for the treatment of Parkinson's disease.
CollTech (Subiaco, Australia) has developed a patented process for extracting collagen from sheep (ovine) skins using a closed, veterinary-controlled and disease-free herd, thereby obviating the concern of "mad cow" disease from bovine-derived collagen. In all, there are 53 million sheep in Western Australia. CollTech's collagen is being sold for food, cosmetic and skin care applications, and a highly purified form will be commercially available by the end of this year, upon completion of a manufacturing plant, for medical and biopharmaceutical uses.
Other developers and commercial suppliers of collagen exhibited their products at the conference. FibroGen (South San Francisco, California) is developing a recombinant collagen and presented a paper on recombinant human gelatin fragments of defined molecular weight and charge for use as biomaterials. Devro Pty (Bathurst, Australia) supplies bovine collagen that is produced from a disease-free cattle herd in Australia for use as a hemostat and in vascular grafts, and is a leading supplier of collagen as an edible sausage casing for the meat products industry.
Encoll (Newark, California) has developed a line of bovine collagen-based products for use in dental surgery and for treating periodontal disease that are sold outside the U.S. They include Periodontal Plus AB, collagen fibrils containing tetracycline; Osseograft, demineralized bone-derived collagen void filler; Osseomold, a mixture of calcium sulfate and collagen for bone regeneration; and Healiguide, a collagen membrane for guided tissue regeneration.
Hi-Por Ceramics Ltd. is a subsidiary of Dyson plc (Sheffield, UK), a supplier of industrial ceramics. Hi-Por is developing medical-grade ceramics that are based on hydroxyapaptite (HAp) and can be cast into multiple shapes. Its products are not yet sold commercially. Synaphor is a highly porous bioceramic implant produced by a patented process that replicates the properties of bone. It is made from synthetic non-resorbable HAp and resorbable biphasic HAp/ -tricalcium phosphate for use as a bioactive scaffold for generating new bone tissue. As a fully synthetic product, Synaphor avoids the problems of disease transmission and lack of suitable donor material that are associated with autografts and allografts. Collagen-coated Synaphor is under investigation at the University of Strathclyde (Glasgow, Scotland) and has been found to yield greater and faster cell proliferation. Hi-Por also is developing a ceramic-biodegradable polymer composite for controlled drug delivery.
Plasma Biotal (Derbyshire, UK) supplies orthopedic companies with HAp and -tricalcium orthophosphate powders for use as coatings on prosthetic joints and for bone grafting. The company also provides a coating service using a plasma process for applying HAp and textured titanium to orthopedic implants.
Professor Hala Zreiqat and her team at the University of New South Wales are researching the enhancement of bone formation at the site where bone meets implant. They reported their findings that the incorporation of magnesium or zinc into a titanium alloy that is commonly used in orthopedic implants alters the molecular component of the implant and enhances bone formation.
MIV Therapeutics (Vancouver, British Columbia) presented details of its nanoporous calcium phosphate thin coating on coronary stents as well as its research conducted at the University of British Columbia (also Vancouver) on in situ formation of nano-dispersed HAp in a poly(propylene fumarate) matrix.
Absorbable Polymers International (Pelham, Alabama), a subsidiary of Durect (Cupertino, California), is in a Phase I trial of bupivacaine contained in its Saber delivery system for use as a spray or paint-on to reduce post-surgical pain. The company has licensed to Pain Therapeutics (South San Francisco, California) an oral gel capsule for oxycodone, a narcotic analgesic.
Polymer Technology Group (Berkeley, California) exhibited its commercial polymers, BioSpan segmented polyurethane, Bionate polycarbonate-urethane, and silicone urethane copolymers, PurSil and CarboSil. The company also offers a selection of developmental and custom polyurethane materials and a new analytical tool, sum-frequency generation, a non-destructive laser technique designed for the study of polymer surfaces.