The ongoing pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a substantial stressor that is greatly impacting environmental sustainability. Besides, the different pre-existing environmental stressors and coronavirus disease-2019 (COVID-19)-related stressors are further worsening the effects of the viral disease by inducing the generation of oxidative stress. The generated oxidative stress results in nucleic acid damage associated with viral mutations, that could potentially reduce the effectiveness of COVID-19 management, including the vaccine approach. The current review is aimed to overview the impact of the oxidative stress damage induced by various environmental stressors on COVID-19. The available data regarding the COVID-19-related stressors and the effects of oxidative stress damage induced by the chronic stress, exposure to free radicals, and malnutrition are also analyzed to showcase the promising options, which could be investigated further for sustainable control of the pandemic.

Graphene has been hailed as a revolutionary membrane material because of its many alluring features and the ease in their tunability. In specific to gas separation industry, the exceptional molecular transport, the possibility of fabricating membranes having thickness at a nanoscale range and the robust lattice structure that can withstand to the rigorous perforation methods render graphene to stand ahead of its contemporary materials. Moreover, its broad chemical tolerance and high mechanical strength facilitate the mass-production of membranes possessing macroscopic dimensions and their subsequent long-term operation under harsh environments. In this concise review, we complied and discussed the progress of gas-separation performance of graphene-based membranes with a prime focus on recent advancements in scalability, functionalization/modification along with the new manufacturing processes including the budding approaches through synthetic chemistry. The strategies implemented, the factors that influenced the membranes'performance and the corresponding transport mechanisms were highlighted in detail. In the end, we outlined the daunting challenges facing by these graphene-based membranes in realization of their prospects as well as the proposed measures for alleviating them.

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Chronic wounds are associated with infectious microbial complex communities called biofilms. The management of chronic wound infection is limited by the complexity of selecting an appropriate antimicrobial dressing with antibiofilm activity due to antimicrobial resistance in biofilms. Herein, the in situ developed bacterial cellulose/poly(vinyl alcohol) (BC–PVA) composite is ex situ modified with genipin‐crosslinked silk sericin (SS) and azithromycin (AZM) (SSga). The composite is evaluated as a wound dressing material for preventing the development, dispersion, and/or eradication of microbial biofilm. Fourier transform infrared spectroscopy confirms the intermolecular interactions between the components of BC–PVA@SSga scaffolds. The addition of PVA during BC production significantly increases the porosity from 53.5% ± 2.3% to 83.5% ± 2.9%, the pore size from 2.3 ± 1.9 to 16.8 ± 4.5 µm, the fiber diameter from 35.5 ± 10 to 120 ± 27.4 nm, and improves the thermal stability and flexibility. Studies using bacteria and fungi indicate high inhibition and disruption of biofilms upon AZM addition. In vitro biocompatibility analysis confirms the nontoxic nature of BC–PVA@SSga toward HaCaT and NIH3T3 cells, whereas the addition of SS enhances cell proliferation. The developed BC–PVA@SSga accelerates wound healing in the infected mouse model, thus can be a promising wound dressing biomaterial.

The unique properties of silk proteins (SPs), particularly silk sericin (SS) and silk fibroin (SF), have attracted attention in the design of scaffolds for tissue engineering over the past decades. Since SF has good mechanical properties, while SS displays bioactivity, scaffolds combining both proteins should exhibit complementary properties enhancing the potential of these materials. Unfortunately, SS-SF composites can generate chronic immune responses and their immunogenic element is not completely clear. The potential of SS-SF composites in tissue engineering, elements which may contribute to their immunogenicity, and alternatives for their preparation and design, to modulate the immune response and take advantage of their useful properties, are discussed in this review. It is known that SS can enhance 𝜷-sheet formation in SF, which may act as hydrophobic regions with a strong affinity for adsorption proteins inducing the chronic recruitment of inflammatory cells. Therefore, tailoring the exposure of hydrophobic regions at the scaffold surface should represent a viable strategy to modulate the immune response. This can be achieved by coating SS-SF composites with SS or other hydrophilic polymers, to take advantage of their antibiofouling properties. Research is still needed to realize the full potential of these composites for tissue engineering.

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