Antimicrobial Interfaces - Biointerfaces: Where Material Meets Biology - page 416

little is known about the conformational properties and interactions of the
individual components of a bacterium in such an interface. Moreover, in-
dividual microbial cells can vary extensively from each other (with regards to
their genetic composition, biochemistry, physiology and behaviour) and
such heterogeneity can have a significant effect on several processes, in-
cluding resistance to antibiotics. Recent developments in nanotechnology
and tools such as atomic force microscopy offers significant breakthrough in
evaluating single cells and molecules. 142,143 These advances should be util-
ised to probe the physical and chemical properties of bacterial cell surfaces
and measure their interactions to understand the unfolding pathways of
membrane proteins, cell-surface polymers (especially their conformational
properties) and the surface receptors localisation. 144 Importance must also
be given to studying the role that the nanoscale surface topography has in
the design and manufacturing of an antibacterial surface. Factors that de-
termine the biocompatibility of the antibacterial surface and/or their tox-
icological consequence need thorough analyses. Until now, only a few
studies have been reported which carry out concurrent experiments to ad-
dress these issues.
So far, the major drawback in most of the reported antibacterial materials
is the longevity of their antibacterial activity. Surfaces which work by re-
leasing antibacterial agents are self-limiting as they tend to release the active
components for only a limited period. On the other hand, newly emerging
surfaces with long-lasting contact-based antibacterial mechanisms are con-
fronted with the accumulation of dead cells which causes weakening of their
ecacy over time. From the material design perspective, a recent report on
the production of biodegradable polymer-supported co-ordination of gal-
lium in gallium carboxymethyl cellulose (Ga-CMC) looks very promising. 145
This is because of the ability of the Ga-CMC material to act as 'suicide pills'
for susceptible pathogenic bacteria such as P. aeruginosa that are capable of
breaking the CMC moiety and releasing the highly active gallium ions. 145
However, surfaces which possess broad spectrum antibacterial activity for
prolonged periods will enhance the application of such materials. So the
quest for biofilm prevention should continue on innovative ideas and
strategies to produce one or more successful solutions.

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Acknowledgements
I thank Dr Christopher K. Hope for his constructive comments during the
preparation of this manuscript.

References
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2. Editorial., Nat. Rev. Microbiol, 2010, 8, 836-836.
3. S. Richard and C. Joanna, Br. Med. J., 2013, 346, f1493.