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Various methods to synthesize diverse nanoparticles with their different applications.

There is a growing demand for durable advanced wound dressings for the management of persistent infections after deep burn injuries. Herein, we demonstrated the preparation of durable antimicrobial nanofiber mats, by taking advantage of strong interfacial interactions between polyhydroxy antibiotics (with varying number of OH groups) and gelatin and their in-situ crosslinking with polydopamine (pDA) using ammonium carbonate diffusion method. Polydopamine crosslinking did not interfere with the antimicrobial efficacy of the loaded antibiotics. Interestingly, incorporation of antibiotics containing more number of alcoholic OH groups (N ≥ 5) delayed the release kinetics with complete retention of antimicrobial activity for an extended period of time (20 days). The antimicrobials-loaded mats displayed superior mechanical and thermal properties than gelatin or pDA-crosslinked gelatin mats. Mats containing polyhydroxy antifungals showed enhanced aqueous stability and retained nanofibrous morphology under aqueous environment for more than 4 weeks. This approach can be expanded to produce mats with broad spectrum antimicrobial properties by incorporating the combination of antibacterial and antifungal drugs. Direct electrospinning of vancomycin-loaded electrospun nanofibers onto a bandage gauze and subsequent crosslinking produced non-adherent durable advanced wound dressings that could be easily applied to the injured sites and readily detached after treatment. In a partial thickness burn injury model in piglets, the drug-loaded mats displayed comparable wound closure to commercially available silver-based dressings. This prototype wound dressing designed for easy handling and with long-lasting antimicrobial properties represents an effective option for treating life-threatening microbial infections due to thermal injuries.

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Understanding and engineering interfaces, and controlling the friction and wear of materials, are extremely important for many technological applications, particularly for magnetic storage technologies and micro-and nanoelectromechanical systems (MEMS and NEMS), where one sliding/moving surface comes into contact with another. Ultrathin carbon fi lms are generally employed in most of these technologies. However, their wear and friction mechanisms are not well understood, especially the role of the fi lm-substrate (FS) interface has not been deeply explored and discussed to date. This limits further developments in this fi eld. Through experimental and theoretical experiments, we are able to report on the engineering of a FS interface consisting of high sp 3and high sp 2 -bonded ultrathin carbon fi lms on Al 2 O 3 -TiC substrates by introducing a silicon nitride (SiN x ) interlayer and tuning the carbon ion energy. All carbon-based overcoats show a low coeffi cient of friction (COF) in the range of 0.08-0.16; however, the high sp 3 -bonded C/SiN x bilayer overcoat reveals the lowest and most stable friction. The friction mechanism is explained using an integrated framework of surface passivation, rehybridization, material transfer, tribolayer formation, and interfaces. We discover that FS interface engineering substantially reduces the wear of ultrathin carbon fi lms while maintaining/ reducing the friction. In general, this approach can be applied to control the friction and wear of ultrathin fi lms of diverse materials.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a new virus in coronavirus family that causes coronavirus disease (COVID-19), emerges as a big threat to the human race. To date, there is no medicine and vaccine available for COVID-19 treatment. While the development of medicines and vaccines are essentially and urgently required, what is also extremely important is the repurposing of smart materials to design effective systems for combating COVID-19. Graphene and graphene-related materials (GRMs) exhibit extraordinary physicochemical, electrical, optical, antiviral, antimicrobial, and other fascinating properties that warrant them as potential candidates for designing and development of high-performance components and devices required for COVID-19 pandemic and other futuristic calamities. In this article, we discuss the potential of graphene and GRMs for healthcare applications and how they may contribute to fighting against COVID-19.