Bacterial cellulose is a naturally occurring polysaccharide with numerous biomedical applications that range from drug delivery platforms to tissue engineering strategies. BC possesses remarkable biocompatibility, microstructure, and mechanical properties that resemble native human tissues, making it suitable for the replacement of damaged or injured tissues. In this review, we will discuss the structure and mechanical properties of the BC and summarize the techniques used to characterize these properties. We will also discuss the functionalization of BC to yield nanocomposites and the surface modification of BC by plasma and irradiation-based methods to fabricate materials with improved functionalities such as bactericidal capabilities.

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Device-associated infections are one of the deadliest complications accompanying the use of biomaterials, and despite recent advances in the development of anti-biofouling strategies, biomaterials that exhibit both functional tissue restoration and antimicrobial activity have been challenging to achieve. Here, we report the fabrication of bio-inspired bactericidal nanospikes in bacterial cellulose and investigate the mechanism underlying this phenomenon. We demonstrate these structures affects preferentially stiff membranes like those in Gram-positive bacteria, but exhibit cytocompatibility towards mammalian cells, a requisite for tissue restoration. We also reveal the bactericidal activity of the nanospikes is due to a pressure-induced mechanism, which depends on the cell's adherence time, nanospike's geometry and spacing, cell shape, and mechanical properties of the cell wall. Our findings provide a better understanding of the mechanobiology of bacterial cells at the interface with nanoscale structures, which is fundamental for the rational design bactericidal topographies.

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In extreme ultraviolet lithography (EUVL) environments both laser produced plasma (LPP) and gas discharge produced plasma (GDPP) configurations face serious issues regarding components lifetime and performance under particle bombardment, in particular collector mirrors. For both configurations debris, fast ions, fast neutrals, and condensable EUV radiator fuels (Li, Sn) can affect collector mirrors. In addition, collector mirrors are exposed to impurities (H,C,O,N), off-band radiation (depositing heat) and highly-charged ions leading to their degradation and consequently limiting 13.5 nm light reflection intensity.The IMPACT (Interaction of Materials with charged Particles and Components Testing) experiment at Argonne studies radiation-induced, thermodynamic and kinetic mechanisms that affect the performance of optical mirror surfaces. Results of optical component interaction with singly-charged inert gases (Xe) and alternate radiators (e.g. Sn) are presented for glancing incidence mirrors (i.e., Ru, Pd) at bombarding energies between 100-1000 eV at room temperature. Measurements conducted include: In-situ surface analysis: Auger electron spectroscopy, X-ray photoelectron spectroscopy, direct recoil spectroscopy and low-energy ion scattering spectroscopy; Ex-situ surface analysis: X-ray reflectivity, X-ray diffraction, atomic force microscopy and at-wavelength EUV reflectivity (NIST-SURF).

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