plants (lotus leafs). A common disadvantage of many nanomaterial
enabled disinfection approaches is the lack of
disinfection residue, which is crucial for controlling microbial
growth during water storage and distribution. Nevertheless,
nanotechnology enabled disinfection can reduce DBP formation
as chlorine or other chemical disinfectants are only
needed as secondary disinfectants. Long term efficacy is
another major uncertainty for all the aforementioned technologies.
Antimicrobial nanomaterials that rely on release of
biocidal ions will be eventually depleted. Controlled release
and the replenish strategies are thus needed. A potential “ondemand”
release strategy is to encapsulate antimicrobial
agents into a matrix gated by materials responsive to the
presence of microorganisms or biofilms. This “on-demand”
mechanism can be further coupled with recognition mechanisms
for targeted release (Fig. 2). For nanomaterials relying
on direct contact, fouling may largely suppress or even eliminate
their antimicrobial activity.