SBIR-STTR Award

The goals of this SBIR project are to develop an antimicrobial nano-coating (AMNC) in order to address these important problems: 1) prevention of nosocomial infections by treating hand contact surfaces (e.g. door knobs, railings and bathroom fixtures) and improving the microbicidal and biofilm preventative properties of materials used in medical care (e.g. indwelling catheters, central lines, prostheses and other invasive devices); and 2) treating dental and surgical instruments to help prevent infections in non-ideal settings (e.g.3rd world or battlefield) where maintenance of sanitary facilities is extremely difficult. The AMNCs will be deposited from the vapor phase using a plasma-enhanced chemical vapor deposition (PECVD) process onto a variety of surfaces. Development of a viable AMNC requires thorough understanding of the following areas: 1) Deposition of nanometer-scale films via PECVD that contain leachable silver ions. These will be synthesized with at least two different matrix polymers (organic and inorganic) and a range of silver content via inclusion of silver-containing precursors in PECVD process. The bioavailability of the active metal ions will be controlled by providing these nanocoatings with a range of hydrophilicity and nanometer scaled porosity. 2) Establishing antimicrobial effectiveness of silver-containing PECVD films as a function of structure and composition; and 3) investigation of the specific mechanisms by which AMNCs inhibit bacterial growth and biofilm development. Film composition, thickness, and morphology are all controllable by suitable choice of specific reactant gases and deposition conditions. A successful Phase I project will result in the demonstration of a nanometer-scale antimicrobial coating that has been tested on a panel of approximately 20 of the top bacterial pathogens.

Thesaurus Terms:
antibacterial agent, antisepsis, biomaterial development /preparation, communicable disease control, disinfectant, silver, surface coating biofilm, hospital equipment /supply, nosocomial infection control, surgery material /equipment nanotechnology

Nosocomial (hospital acquired) infections represent one of the most severe problems facing the health care industry. Of the approximately two million hospital acquired infections reported annually in this country, about half are associated with catheters, ureteral stents, central lines and other percutaneous devices that provide a support surface for organisms to track into deeper tissue. A typical infection can cost as much as $47,000 per patient to treat. Although invasive medical devices such as stents and catheters are pre-sterilized and inserted or implanted under the most sterile conditions available; biofilm growth, encrustation, and subsequent infection are the most common mode of failure. Coatings that could render these devices inherently resistant to biofilm formation and encrustation could significantly reduce the incidence of infections and unnecessary illness, allow better use of health care resources, reduce healthcare costs, and save lives. Encrustation results from mineral incorporation into biofilms on device surfaces. These deposits inhibit drainage; are virulent bacterial reservoirs; and increase susceptibility of the local tissues to infection. Antibiotic strategies have proven to be of little value in preventing biofilm formation and encrustation of stents and catheters. One technique for producing antimicrobial surfaces is to apply a coating which is capable of releasing metal ions when exposed to moisture. Antimicrobial silver ions are particularly useful for in vivo use due to the fact that they are not substantially absorbed into the body. In Phase I, Brighton Technologies Group developed and characterized a novel antimicrobial nanocoating (AMNC) based on gas-phase deposition of a silver salt-containing polymer that effectively inhibits biofilm formation for a wide range of microorganisms. Phase II will extend these results to create an antimicrobial surface that will inhibit biofilm formation and encrustation on medical devices such as stents and indwelling catheters through: 1. Developing techniques for depositing these films on urinary devices such as ureteral stents, Foley catheters, and ureteral catheters. 2. Evaluating important AMNC characteristics such as hydrophobicity/hydrophilicity, coefficient of friction, adhesion and wear resistance. 3. Developing predictive knowledge of activity and effective lifetime of AMNC's as a function of structure and composition. 4. Initiating in vivo performance and biocompatibility evaluations. Approximately two million hospital-acquired infections are reported annually in the USA, 90,000 of which result in death. Reducing the spread of infectious diseases within healthcare facilities, and in the general community would ultimately translate to saving lives, increasing productivity, and improving the quality of life for millions. Brighton Technologies Group, Inc.'s Antimicrobial Nanocoating is designed to render medical device and hand-contact surfaces self-sterilizing to eliminate some the most common conduits for infection transmission