Inorganic Nanoparticles and Composite Films for Antimicrobial Therapies

Abstract

The development of drug-resistant microorganisms has become a critical issue for modern medicine and drug discovery and development with severe socio-economic and ecological implications. Since standard and conventional treatment options are generally inefficient, leading to infection persistence and spreading, novel strategies are fundamentally necessary in order to avoid serious global health problems. In this regard, both metal and metal oxide nanoparticles (NPs) demonstrated increased effectiveness as nanobiocides due to intrinsic antimicrobial properties and as nanocarriers for antimicrobial drugs. Among them, gold, silver, copper, zinc oxide, titanium oxide, magnesium oxide, and iron oxide NPs are the most preferred, owing to their proven antimicrobial mechanisms and bio/cytocompatibility. Furthermore, inorganic NPs can be incorporated or attached to organic/inorganic films, thus broadening their application within implant or catheter coatings and wound dressings. In this context, this paper aims to provide an up-to-date overview of the most recent studies investigating inorganic NPs and their integration into composite films designed for antimicrobial therapies.

Iron Oxide–Silica Core–Shell Nanoparticles Functionalized with Essential Oils for Antimicrobial Therapies

“…Moreover, the increased antimicrobial activity of the nanoparticles synthesized through the hydrothermal method could be related to the smaller Fe 3 O 4 nanoparticle size, which is generally associated with a higher capacity to penetrate and disrupt microbial cell walls [ 9 ]. Furthermore, since there was a higher amount of silica within these samples, the intrinsic antimicrobial activity of the Fe 3 O 4 nanoparticles could be reduced due to the limited contact between the cores and the bacterial cells.…”

“…While ancient times witnessed the deaths of more than half of born individuals before reaching sexual maturity [ 8 ], the discovery of antimicrobial drugs has greatly impacted the global health system by significantly reducing morbidity and mortality associated with infectious diseases [ 9 ]. However, microorganisms have acquired or developed numerous resistance mechanisms over time against all commercially available antimicrobial drugs [ 9 , 10 ].…”

“…While ancient times witnessed the deaths of more than half of born individuals before reaching sexual maturity [ 8 ], the discovery of antimicrobial drugs has greatly impacted the global health system by significantly reducing morbidity and mortality associated with infectious diseases [ 9 ]. However, microorganisms have acquired or developed numerous resistance mechanisms over time against all commercially available antimicrobial drugs [ 9 , 10 ]. The main causes involved in the development of such mechanisms include genetic modifications of microorganisms, gratuitous over-prescription of antibiotics and broad-spectrum antibiotics, easy access to over-the-counter antibiotics, and contaminations due to antimicrobial drug manufacturing [ 11 ].…”

“…The main causes involved in the development of such mechanisms include genetic modifications of microorganisms, gratuitous over-prescription of antibiotics and broad-spectrum antibiotics, easy access to over-the-counter antibiotics, and contaminations due to antimicrobial drug manufacturing [ 11 ]. As antimicrobial resistance has led to ineffectiveness of currently existing drugs, a worldwide catastrophic issue for the public system, there is an urgent necessity to identify novel alternative strategies [ 5 , 7 , 9 , 11 , 12 , 13 , 14 , 15 ].…”

Biomaterials for the Prevention of Oral Candidiasis Development

“…Several nanoscale metal oxides have also been observed to have antifungal properties. Nanoparticles of iron oxide [85][86][87][88], zinc oxide [89][90][91][92][93], magnesium oxide [93][94][95][96], calcium oxide [94,97], copper oxide [98][99][100], titanium dioxide [101][102][103][104], bismuth oxide [105,106], and silver oxide [107] display fungistatic and/or fungicidal activities that are useful in the treatment and prevention of oral candidiasis.…”