2050 (Fig. 27.2) that will add an economic burden of 100 trillion USD, unless

serious measures are taken against microbial resistance.

Thus, there is a critical need for the development of new antimicrobial

technologies as alternatives to, or to work in combination with, conventional anti-

microbial treatment methods. The use of metal-based engineered nanomaterials

(ENMs) possessing antimicrobial properties has already started addressing many

of these criteria, with varying success. In particular, metal and metal oxide ENMs

have been studied extensively as they possess a range of innate antimicrobial

mechanisms, including the disruption of the cellular membrane, diffusion into and

degradation of internal cellular components such as DNA, RNA, and enzymes and

the release of ions with antimicrobial activity. Common materials include but are not

limited to silver (Ag), gold (Au), copper (Cu), zinc (Zn), titanium (Ti), magnesium

(Mg), calcium (Ca), nickel (Ni), iron (Fe), palladium (Pd), tellurium (Te), platinum

(Pt), silicon (Si), and their corresponding oxides in some cases, with a range of

shapes and sizes (typically in nanometre range) (Table 27.1).

27.2

Fabrication Techniques

The design of synthetic techniques has been commonly recognized as a key area for

understanding and application of ENMs. The size and shape of ENMs have strong

effect on their properties, thus, demands their morphology and dimensions to be

controlled precisely during synthesis. Metal-based ENMs can be easily synthesized

Fig. 27.2 Annual deaths attributable to AMR compared to other major causes of death (O’Neill

2018)

498

M. Chauhan et al.