Nanotechnology Approaches to Treating Antimicrobial Resistant Infections Caused by Biofilms: Research Needs for Translation from In Vitro to In Vivo Applications

Antimicrobial resistance [AMR] to antibiotics and the multi drug resistance phenomenon has become a burden posing a critical challenge in public health, causing morbidity, increased treatment cost and fatalities. Analysis reveals 65-80% of infections to be associated with biofilms that are 100-1000 times less susceptible to antibiotics compared to their planktonic counterparts. The failure of conventional antibiotics and an increase in AMR microbes has warranted the need for alternative antimicrobials. Nanoparticles, namely: metals, metal-oxides, natural and synthetic polymers in the nanoscale between 1-100nm have been very effective in combating MDR pathogens and their biofilms. Nanoparticles in the size range of 1-20nm have been shown to possess very low MICs ranging from 1.6-25µg/mL, essentially the concentration ranges at which most of the antibiotics work. For in-vivo application of nanoparticleS, norms of the therapeutic index have to be met. Synthesis of metal and metal-oxide nanoparticles [MONs] in the size ranges of 1-20nm has been another challenging task. In lieu of this, there has been a quest for studies investigating novel synthesis routes to obtain NPs of low size, exhibiting low MICs and broad-spectrum activity. The need of the hour is to concentrate on studies aimed at synthesizing MONs in the range of less than 10nm with low MICs and therapeutic ratios and to carry out preclinical studies using animal models followed by clinical trials for biofilm control. This chapter deals with emerging efforts, novel approaches, concepts and developments in the application and efficacy of nanomaterials and their realization as potent alternatives.