  Citation: Munir, M.U.; Ahmad, M.M. Nanomaterials Aiming to Tackle Antibiotic-Resistant Bacteria. Pharmaceutics 2022, 14, 582. https:// doi.org/10.3390/pharmaceutics14030582 Academic Editors: Elia M. Grueso and Rosa María Giráldez-Pérez Received: 9 February 2022 Accepted: 4 March 2022 Published: 7 March 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). pharmaceutics Review Nanomaterials Aiming to Tackle Antibiotic-Resistant Bacteria Muhammad Usman Munir 1, * and Muhammad Masood Ahmad 2 1 Department of Pharmaceutical Chemistry, College of Pharmacy, Jouf University, Sakaka 72388, Aljouf, Saudi Arabia 2 Department of Pharmaceutics, College of Pharmacy, Jouf University, Sakaka 72388, Aljouf, Saudi Arabia; mmahmad@ju.edu.sa * Correspondence: mumunir@ju.edu.sa Abstract: The global health of humans is seriously affected by the dramatic increases in the resistance patterns of antimicrobials against virulent bacteria. From the statements released by the Centers for Disease Control and Prevention about the world entering a post-antibiotic era, and forecasts about human mortality due to bacterial infection being increased compared to cancer, the current body of literature indicates that emerging tools such as nanoparticles can be used against lethal infections caused by bacteria. Furthermore, a different concept of nanomaterial-based methods can cope with the hindrance faced by common antimicrobials, such as resistance to antibiotics. The current review focuses on different approaches to inhibiting bacterial infection using nanoparticles and aiding in the fabrication of antimicrobial nanotherapeutics by emphasizing the functionality of nanomaterial surface design and fabrication for antimicrobial cargo. Keywords: antimicrobial nanomaterial; antibiotic resistance; metallic nanoparticle; bacterial biofilm; multidrug-resistant bacteria 1. Introduction The most important current issue related to human health is bacterial resistance against antibiotics. One survey estimates approximately two million cases of severe illnesses caused by bacterial resistance to antibiotics, and 23,000 deaths are reported annually in the U.S. The latest research shows that infection caused by bacteria will be approximately ten million annually in the future [1], which is much greater than recent cancer numbers [2]. Prolonged treatment using antibiotics is required in multidrug-resistant conditions, along with debridement of tissue, but in a small number of cases, the high costs of healthcare and low patient compliance prevent this treatment from succeeding. Estimated reports indicate that in the U.S., societal and health costs annually total almost USD 55 billion [3]. In addition, bacterial cell tolerance is increasing due to the increased use of antibiotics caused by bacterial resistance. It is known from a literature survey from U.S. hospitals that 46–60% of isolated bacterial strains of S. aureus are resistant to methicillin and even to vancomycin and carbapenems in some instances [4]. The focal target of antibiotics is mainly on cell wall inhibition, protein synthesis, RNA, and DNA. Bacteria have an intrinsic ability to overcome antibacterial threats by transferring and changing the form of DNA [5,6]. The same microbe can acquire multi-drug resistance that evolves in different organisms. Recent research has shown that super-resistance by resistant bacterial gene NDM-1 in beta-lactam antibiotics causes enzymatic degradation and bacterial resistance against many antibiotics [7]. In current antibiotics, multidrug-resistance in tuberculosis-causing bacteria (mycobacterium) has been reported [3,8]. Resistance against antibiotics will flourish in bacteria, and the growth of more multi-drug-resistant strains of bacteria will be enhanced. It is a formidable situation that requires discoveries of new antibacterial therapies to combat highly resistant bacteria [9]. Pharmaceutics 2022, 14, 582. https://doi.org/10.3390/pharmaceutics14030582 https://www.mdpi.com/journal/pharmaceutics