Anti-microbial and Anti-inflammatory Materials & Surfaces, and Monitoring Technologies

Biomaterial-centred and medical device-related infections and sustained inflammation are a major health care problem today with an adverse impact on the quality of life of patients, prolonged hospital stays and high costs. One reason of implant infection is the combination of primary infection during surgery or contamination in the event of a trauma with the slow healing and insufficient integration of the implant material. Although progress has been made in recent years in the protective strategy for some medical device infection, the risk of implant-associated infection is still considerable with > 30% in open polytrauma fractures, 10-30% for cardiovascular systems, and 2-5% for orthopaedic devices. Furthermore, degradation products or substances released over long time periods of implanted devices may induce chronic inflammation or an undesirable immune response in a considerable number of patients.

Various surface modification strategies, particularly topographical and (bio)chemical ones, have been addressed in the past to reduce the risk of interfacial biofilm formation and infection and thereby prevent sustained inflammation at implant sites. Such approaches include (a) creation of surface properties that favour differential host cell attachment and device integration of implants over bacterial colonization and biofilm formation, increasing the chances of host cells to win the “race for the surface”. (b) The functionalisation of materials and surfaces with anti-microbial and/or anti-inflammatory components, either as “permanently” bound moieties or as controlled release systems.

More recently proposed research concepts aimed at overcoming some of the inherent drawbacks of current approaches, which are, for example, development of resistance, reduced activity when surface-linked, rapid loss of anti-microbial functionality as a consequence of, for example, dead bacteria debris contamination, or cell toxicity risk. Promising novel approaches include (i) Molecularly designed biocidal/anti-inflammatory drug release systems with a well controlled spatio-temporal release profile and/or exploiting a dual drug delivery strategy; (ii) The use of anti-microbials evolutionary developed by plants or animals, e.g., agents known to interfere with the bacteria’s quorum sensing mechanism, and anti-microbial peptides, for which development of bacterial resistance has rarely been reported; (iii) Strategies aimed at locally detoxifying implant surfaces or releasing substances in order to prevent development of chronic inflammation. Concurrently, there is an important need for more predictive, efficient and statistically significant assays compatible with bioactive interfaces, such as novel methodology based on the use of surface-functionalized, bioactive microparticles suspended in bacterial cultures combined with efficient readouts such as FACS.

• Biocompatible Films, Foams, Fabrics, and Surfaces from Poly(isobutylene)–Oligopeptide Conjugates - Project approved, to start in 2010

• Serrulatane-based  antimicrobial surface platforms - Project approved, to start in 2010