Biocide-releasing surfaces

Abstract In this review, the general principles of antimicrobial surfaces will be discussed in detail. Because many common products that keep microbes off surfaces have been banned in the past decade, the search for alternatives is in full run. In recent research, numerous new ways to produce so-called self-sterilizing surfaces have been introduced. These technologies are discussed with respect to their mechanism, particularly focusing on the distinction between biocide-releasing and non-releasing contact-active systems. New developments in the catalytic formation of biocides and their advantages and limitations are also covered. The combination of several mechanisms in one surface modification has considerable benefits, and will be discussed. 

The first contact-killing surface was described by Isquith et al., who modified glass substrates with the silane 3-(trimethoxysilyl)-propyldimethyloctadecylammonium chloride, often referred to as DOW5700 [39], However, the claim was made on the basis of the DOW suspension test (see Sect. 2.2), which cannot distinguish between biocide release and contact activity. In subsequent work, neither the original authors nor followers proposed a working model for a mechanisms that was able to explain the contact activity of this surface modification. The first model for contact activity was proposed in 2001 (see Fig. 5) [40],... 

All release systems that liberate an immobilized biocide into the surroundings will exhaust rather quickly. Furthermore, the constant release is an environmental issue and supports the building of biocide-resistance in microbial strains. If a release system is the only possible option, then it would be desirable to release the biocide on demand, e.g., in cases of infection or the start of biofilm formation. This can be achieved by either degrading or swelling the matrix with an infection-specific enzyme or metabolite, or by cleaving the linker between biocide and surface with a biochemical factor. 

Fig. 8 Concept of simultaneous microbe repulsion and biocide release of a specifically designed network. The network is composed of poly(2-hydroxyethylacrylate) crosslinked with polyethyleneimine and surface-grafted with polyethylene glycol. The polyethyleneimine junctions take up silver ions, which then form nanoparticles due to the template character of these nanocontainers. Reproduced and adapted from [90]...

Poly [2- (t-butylamino)ethy 1 methacrylate]-f-amine/PP-g-MA Melt processed as fibers/antibacterial activity against E. co/i/copolymer formation prevented release of the polymethacrylate biocide from surface of fibers Thomassin et al. 2007... 

Contact biocidal biomaterial surfaces kill bacteria on contact as the bactericidal agents are not released and are active following direct interaction with the bacterial cells. Acting through direct contact with bacteria, however, these bioactive surfaces can... 

Triggered Release of Bacterial Cete from Biocidal Nanopattemed Surface... 

Keywords Antibacterial Antimicrobial Bacteria Biocide Contact-active Light-activated Photocatalytic Release Self-polishing Surface... 

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