**Author details**

*Materials at the Nanoscale*

stream [67, 71].

**10. Conclusion**

resistant pathogens.

with nanoparticle exposure. [65]. Impact of NPs on beneficial bacteria in humans should be of high concern [66, 67]. It has been reported that NPs can cause hemeolysis thus, may impair blood coagulation [68]. The precise mechanism of toxic effects of NPs is not so clear, but it has been observed that nanoparticles larger in size pose a greater threat on human health. In most of the invitro studies conducted on AgNPs, it has been observed that AgNPs are more toxic for cell lines [69, 70]. Deposition of AgNPs has been observed in many organs such as liver, lungs, spleen which has been linked to organ damage [24]. In blood and urine of burn patients elevated levels of Ag have been reported, this may be due to leaching from Ag wound dressing (Acticoat®),which is composed of Ag nanocrystals, into the blood

Neurotoxicity has been associated with Al2O3 NPs which interact with cellular components [33]. CuONPs have been observed to induce oxidative damage. CuO NPs induce hepatotoxicity and nephrotoxicity through the generation of free radical-mediated oxidative stress [20, 72, 73]. DNA damage has been associated with ZnO or TiO2 NPs thus, limiting their use [24]. Hagens et al. [74] have reported that NPs that are administered intravenously could get accumulated in bone marrow, colon, lung, liver, spleen as well as lymphatic system. Inhalation of NPs has

In various *in vivo* studies, it has been reported that there is lethal toxicity associated with the use of NPs [29, 76–78]. Nevertheless, the assessment of toxicity at the cellular level as well as mode of administration is crucial for clinical use of NPs [67].

Silver and Zinc NPs have the ability to interact with and influence the growth of a variety of microorganisms. Therefore, Ag and Zn NPs could be employed as a broad-spectrum antibiotic agents to combat bacterial infections. Plant extracts are used to make Ag and Zn NPs, which is cost-effective and eco-friendly. The antibacterial action of Ag and Zn NPs appears to be attributed to their structure, ultrasmall size, and increased surface area, which allows them to damage and pass the bacterial membrane that is responsible for intracellular damage. It has been described that NPs in combination with antibiotics can be a promising strategy to overcome bacterial resistance. Synthesis of Ag and Zn NPs via green-synthesis methods and mechanisms of action against bacteria have been elucidated. We have also shed light on toxicity associated with the use of NPs. Ultimately, it can be conluded that both Ag and Zn sNP have broad-spectrum antibiotic activity against bacteria, making them prospective therapeutic agents for bacterial infections and multidrug-

been associated with cytotoxicity in the lungs [75].

**166**

Gulzar Ahmed Rather1 \*, Saqib Hassan2,3, Surajit Pal2 , Mohd Hashim Khan4 , Heshu Sulaiman Rahman<sup>5</sup> and Johra Khan6

1 Department of Biomedical Engineering, Sathyabama Institute of Science and Technology, Deemed to be University, Tamil Nadu, India

2 Department of Microbiology, School of Life Sciences, Pondicherry University, Puducherry, India

3 Division of Non-Communicable Diseases, Indian Council of Medical Research (ICMR), New Delhi, India

4 School of Life Sciences, B.S. Abdur Rahman Crescent Institute of Science and Technology, Tamil Nadu, India

5 Department of Physiology, College of Medicine, University of Sulaimani Kurdistan Region, Iraq

6 Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Majmah University, Kingdom of Saudi Arabia

\*Address all correspondence to: rathergulzar5@gmail.com

© 2021 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
