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Toward the objective of developing platform technologies for anti-infective materials based upon photodynamic inactivation, we employed electrospinning to prepare a non-woven textile comprised of polyacrylonitrile nanofibers embedded with a porphyrin-based cationic photosensitizer; termed PAN-Por(+). Photosensitizer loading was determined to be 34.8 nmol/mg material; with thermostability to 300° C. Antibacterial efficacy was evaluated against four bacteria belonging to the ESKAPE family of pathogens (Staphylococcus aureus; vancomycin-resistant Enterococcus faecium; Acinetobacter baumannii; and Klebsiella pneumonia), as well as Escherichia coli. Our results demonstrated broad photodynamic inactivation of all bacterial strains studied upon illumination (30 min; 65 ± 5 mW/cm²; 400-700 nm) by a minimum of 99.9996+% (5.8 log units) regardless of taxonomic classification. PAN-Por(+) also inactivated human adenovirus-5 (~99.8% reduction in PFU/mL) and vesicular stomatitis virus (>7 log units reduction in PFU/mL). When compared to cellulose-based materials employing this same photosensitizer; the higher levels of photodynamic inactivation achieved here with PAN-Por(+) are likely due to the combined effects of higher photosensitizer loading and a greater surface area imparted by the use of nanofibers. These results demonstrate the potential of photosensitizer-embedded polyacrylonitrile nanofibers to serve as scalable scaffolds for anti-infective or self-sterilizing materials against both bacteria and viruses when employing a photodynamic inactivation mode of action. [ABSTRACT FROM AUTHOR]

Towards the development of novel platforms for oil absorption and environmental remediation, bacterial cellulose aerogels (BCA), a lightweight and highly porous material, were modified with carbon nanotubes (CNT) and carboxylic carbon nanotubes (CCNT), respectively, at both 5 and 10 wt % loading. The resulting nanocomposite materials, termed BCA/CNT and BCA/CCNT, demonstrated improved oil absorption property when tested against liquid paraffin (glycerol), vacuum oil, plant oil, and propanetriol. After a single immersion lasting about 4–119 seconds, BCA/CNT 10% absorbed an average of 120.23 (standard deviation: 1.145) g·g−1 of propanetriol. While BCA is known to be fragile, but no destruction was observed before and after oil absorption. The difference between CNT and CCNT is carboxylation, which could reduce hydrophilicity. The samples were characterized by scanning electron microscope (SEM), Fourier transform infrared spectrum (FTIR), Brunauer–Emmett–Teller (BET) analysis, contact angle test, and mechanical test. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48000. [ABSTRACT FROM AUTHOR]

Pesticide residues (PR) present in food are potentially toxic components to humans and can be the cause of severe health problems, depending on the means and amounts of individual exposure. Among the different routes of pesticide exposure, the most likely exposure is through the direct consumption of fresh foods. To remove PR from fresh agricultural products and improve food safety for consumers, various pesticide removal methods have been studied in recent decades. Several cleaning techniques such as usage of surfactants, ozone (O 3), ionic solvent, and chlorine treatment have been applied to reduce the presence of pesticides. However, none of these methods have been reported as being successful in removing PR without any physical or chemical side effects to the food itself. Therefore, there is a crucial need for investigation of more effective, sustainable, and environment-friendly pest and pesticide removal practices. Ultrasound-assisted cleaning (UAC) is considered to be an environment-friendly and effective pesticide eliminating process which is unique in its ability to remove the contaminants compared to conventional methods. It is also a time and energy-saving method of cleaning. This review gathers and focuses on the most relevant works on the UAC techniques of organic or inorganic pesticides applied during the growth of fresh vegetables, which are mostly eaten raw or after minimal processing. The findings of the reviewed works suggest that ultrasonication itself would be beneficial as a vegetable-cleaning technology, or could be readily combined with another suitable method. • Commonly used pesticides in fresh vegetables and their residual effects are studied. • Ultrasound-assisted cleaning and conventional pesticide removing methods are reviewed. • The efficacy of ultrasound sanitizing in the removal of pesticide residue is summarized. • Conceivable ways of achieving synergism effects are recommended. • Scopes and limitations of ultrasonication in removing pesticides are outlined. [ABSTRACT FROM AUTHOR]