Biofilms are bacterial communities encased in a self-produced hydrated polymeric matrix. An important characteristic of microbial biofilms is their innate resistance to the immune system and to antibiotics. This resistance has made microbial biofilms a common cause of medical infections, and of difficult-to-treat infections caused by colonized foreign bodies. Prevention of biofilm formation is a necessary step in the successful prophylaxis of such infections. More than 60% of bacterial infections currently treated in hospitals are caused by bacterial biofilms. Biofilms are a major cause of infections associated with medical indwelling implants such as catheters. The number of implant-associated infections approaches 1 million/year in the US alone,and their direct medical costs exceed $3 billion annually. Catheter-associated biofilm urinary tract infections (UTI) alone account for approximately 40% of all hospital-acquired infections
Attempts to avoid implant biofilm formation were based mainly on biological mechanisms.
One of the reasons for low efficiency of the existing methods is the non-specific adsorption of organic matter, e.g. proteins, originating from the host on the catheter. The adhesion of these bio-contaminants can restrict the antibacterial activity of the applied antiseptics, and enhance the bacterial growth. Protein adsorption and the subsequent formation of a layer of protein on the surfaces of the catheter provide a conditioning layer for microbial colonization and subsequent bioﬁlm formation.
As a result, urologists have to remove the catheter from the patient after 24-48
hours along with prolonged antibiotic therapy in case of infection, which incurs additional health care costs.
Thus, the overall objective of NOVO project was to develop a technological platform to prevent biofilm production, based on novel and complementary antibacterial agents coated via a novel ultrasonic (US) process. This process is a single step, efficient, environmentally friendly (based on water solution) and low cost.
The strategies to prevent biofilm formation are functionalisation of catheters’ surface with:
A. Inorganic nanoparticles (NPs)
B. Organic polymers
The above complementary approaches were studied also in their combinations and applied on latex and silicone catheters.
The project proved by in vivo studies extention of usage of the coated catheters up to 7 days by preventing biofilm formation while maintaining a significant reduction in the risk of urinary tract infections (UTI) and significant reduction in the need for antibiotic therapy.
It is estimated that the cost of the new catheters will be only 10% higher than the existing products.