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Herein, we exploited xanthan gum (XG) and cationic dextran (CD) in designing a novel porous aerogel (XCD) loaded with different concentrations of a new bistriazole derivative (CPSC). The CPSC was deposited into and onto the pores of aerogels. The neat aerogel removed both AB40 dye and Cu2+ efficiently. Adding 0.5 g of CPSC to the neat aerogel (XCD-0.50 sample) improved slightly the adsorption of Cu2+ and has no effect on the adsorption of AB40 dye. XCD-0.50 removed almost completely 10 mg/L of AB40 dye in 10 min using 0.5 g/L at pH i 6 while for Cu2+ longer contact time (90 min) and higher dosage (2.0 g/L) were required to remove 10 mg/L solution at pH i 5. Relative to literature, the Langmuir adsorption capacity of XCD-0.5 toward AB40 dye (436 mg/g) was the highest and toward Cu2+ (60 mg/g) was comparable to others. The aerogel XCD-0.50 was regenerable and reusable for three cycles with reasonable efficiency. By submerging a bacterial solution (106 CFU/mL) in the XCD-0.75 aerogel for 90 min, an impressive 6-log decrease in the number of bacteria was obtained under ideal circumstances. Crucially, toxicity test clearly confirmed that the prepared aerogels had non-toxic impact. Across all investigated bacterial species, XCD-0.75 continuously achieved a 6-log CFU decrease after 180 min, demonstrating its efficacy in the context of disinfection experiment. The results of the study highlight the extraordinary potential of the biopolymer aerogel loaded with CPSC as a potent adsorbent and disinfectant. They show significant removal of toxic trace elements and dyes, along with microbial reduction in industrial wastewater, underscoring the aerogel's potential use in water treatment. [ABSTRACT FROM AUTHOR]

Introduction Thermo-responsive hydrogels are promising biomedical systems as their gelation is triggered by temperature changes. Greenly synthesized noble metallic nanoparticles are a growing research area assessing their potential applications in nanomedicine. Materials and methods Chitosan/phosphate thermosensitive gels were successfully achieved. The developed composite scaffolds were functionalized with the greenly synthesized Ag or Ag@Pd targeting improved bactericidal activity and biocompatibility performance. The physicochemical characterization was assessed through TGA, DSC, FESEM, HRTEM, XRD and FTIR. Bactericidal activities were tested against gram- positive Staphylococcus aureus and gram-negative Pseudomonas aeruginosa . Their biodegradability upon DMEM immersion was followed up to seven days through measuring ionic concentrations of Ca, P, Ag and Pd successively. Key findings The newly developed phosphatic layers over the scaffold surfaces post-immersion assessed their osteogenic ability. Further, their promising and differentiated bactericidal activities due to the noble metals incorporation were proved. Cytotoxicity assessment demonstrated their high biocompatibility since no toxic effect was recorded. Significance Consequently, they can be successfully and directly applied in biomedical and dental surgeries. [ABSTRACT FROM AUTHOR]

Current research targets innovative medical textiles of nanofibrous nature and antibacterial activity to prevent diaper dermatitis. The work is based on electrospun nanofibers from cellulose acetate (CA) and lignin (Lig) polymers. A series of new copper complexes were synthesized and loaded to the CA/Lig solution mix then subjected to electrospinning, giving rise to the tricomponent bioactive mats CA/Lig/Cu-complex. The surface morphology of electrospun nanofiber mats was smooth and homogenous as the concentration of lignin increased in the mixture. The incorporation of lignin improved the electrospinnability of the cellulose acetate; however, it increased the fiber diameter. The water contact angle, absorption underload were significantly improved as lignin content increased. The incorporation of Cu-complex in electrospun CA and CA/Lig fiber mats occurred without any substantial change in the surface morphology, indicating well encapsulation of the complex. The electrospun mats were active against Pseudomonas aeruginosa , Acinetobacter baumannii , Staphylococcus epidermidis , and Streptococcus faecalis. The cytotoxicity, protein leakage, and biological results, together with the above studies, would advocate copper complex loaded CA/Lig nanofibers as a potential candidate for hygienic applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract The ability of Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, Human adenovirus serotype 2 (HAdV2) and Murine Norovirus 1 (MNV-1) to survive in river water at −20, 4, room temperature (~24 °C) and 37 °C, were evaluated under dark conditions. The tested surface water was obtained from the main Nile River in the Dokki area, Giza and sterilized by autoclaving. The pathogens were inoculated separately in the autoclaved river water. Each microcosm was sampled and the test microorganisms counted after zero (immediately following inoculation), 1, 7, 15, 30, 60, 90 and 120 days. Physicochemical parameters including pH, turbidity, electrical conductivity, dissolved oxygen, total dissolved solids, total alkalinity, biological oxygen demand, chemical oxygen demand, nitrates and nitrites, and sulphate, were also measured. For HAdV2, the highest decay rates were observed at 37 °C and room temperature compared to 4 and −20 °C. A similar trend was found for the MNV-1, although unlike the HAdV2, the decay rate was higher at −20 than at 4 °C. Also, 4 °C was the best temperature for the survival of MNV-1 (T 90 = 76.9 days), E. coli O157:H7 (T 90 = 103 days) and Salmonella Typhimurium (T 90 = 105 days). The least survival of the pathogens, except MNV-1, was recorded at 37 °C. These results indicate that under dark conditions and low temperatures, enteric pathogens could be stable for extended periods. No significant statistical correlation was observed between the experimental temperatures and the infectivity of the viral particles. This study provided useful information about the stability of these pathogens in the Nile River water and could serve as an early warning when considering the water of the river for agricultural irrigation or household use in areas with limited or no access to potable water. Graphical abstract Unlabelled Image Highlights • Survival of enteric bacteria and viruses was investigated in Nile River water. • Salmonella , E. coli O157:H7 and HAdV2 survived for over >100 days of the experiment. • Lower temperatures (4 and −20 °C) favoured the survival of the test pathogens. • Viral pathogens retained their infectivity throughout the study period. • This extended survival could be a public health hazard for users of the Nile River water. [ABSTRACT FROM AUTHOR]

Abstract We herein describe the synthesis of four Cs-PVC conjugates three of them were functionalized with benzothiazole (BTh) derivative as an antibacterial agent. Two of these BTh-functionalized conjugates, namely Cs2 and Cs3, comprise silver nanoparticles (AgNPs) and Ag/TiO 2 NPs, respectively. The structures were characterized via FTIR spectroscopic analysis, morphological investigation such as scanning (SEM) and transmission (TEM) electron microscopy, and thermal gravimetric analysis (TGA). Spectral data confirmed the introduction of the BTh to the Cs backbone as well as the coupling between the two polymers. SEM data showed homogenous polymer surfaces with well-distributed Ag nanoparticles. The Ag contents in the prepared samples Cs2 and Cs3 were, respectively, 0.61 and 0.21%, however, TEM analysis showed that the sizes of AgNPs and Ag/TiO 2 NPs were in the range of 3–7 nm and 15–22 nm for the prepared conjugates, respectively. The antibacterial activity of the synthesized conjugates was investigated against two Gram-negative (E. coli , and S. typhimurium) and two Gram-positive (S. aureus , and L. monocytogenes) bacteria. The antibacterial assay showed that all three Cs-PVC (Cs1, Cs2, and Cs3) conjugates modified with BTh exhibited excellent bacterial inhibition after 30, 60, and 120 min. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biocompatible polycaprolactone (PCL) nanofibers/peppermint oil (PO) nanoemulsion was prepared. • The antimicrobial action of PCL/PO was approximately-four times greater than that of the pure PO against all tested pathogenic microbes. • The results showed extensive damage had occurred in the cell membranes after treatment with PCL/PO nanofibers. Formulating nanofibers loaded with active compounds for biomedical purposes has recently drawn great attention. In this work, polycaprolactone (PCL) was blended with peppermint oil (PO) nanoemulsion to fabricate an antimicrobial nanofiber scaffold via electrospinning technique. The electrospinning solutions of PCL were loaded with different concentrations ofPO nanoemulsion (PCL-1, PCL-2, PCL-3, and PCL-4). The findings illustrated that; PO emulsion droplets were in the nano-range (150–200 nm) which promoted their inclusion inside the fibers. Further, there was no significant difference between the unloaded and loaded PCL nanofibers in terms of surface morphology and mechanical properties. The PO-loaded PCL electrospun composites exhibited powerful antibacterial and antifungal activities. PCL-4 for instance showed four times greater antimicrobial activity than PO nanoemulsion. The physiological kinetic experiment showed that PCL-4 had nearly prohibited all tested microbes from the start of the experiment with extensive damage to their cell membranes whereas PO nanoemulsion showed only 50 % prohibition. To conclude, the powerful antimicrobial activity of the prepared PO nanoemulsion loaded PCL nanofiber could be implemented as dermal patches against acne and skin disorders caused by planktonic and biofilm cells. To conclude, the nanofibers of PCL loaded with PO nanoemulsion is considered a forceful antimicrobial mats and brings advantageous in preparing dermal patches for acne treatment or skin disorders. Hence, PCL-4 could be successfully applied to prohibit the growth of human pathogens in planktonic and biofilm states that cause skin diseases. [ABSTRACT FROM AUTHOR]

We study the microstructure, optical, thermal, dielectric, and mechanical properties of flexible oxidized cellulose (OC) films loaded with different mass fractions of cubic structure Bi 0.5 Na 0.25 K 0.25 TiO 3 by blending solution technique and casting method. The films were characterized using infrared, X-ray diffraction, scanning electron microscopy, and UV–visible spectroscopy. The optical results confirmed the formation of crystalline bismuth sodium titanate/OC semiconductor films with a direct energy bandgap (3.002–3.276 eV) and have the ability for optoelectronic applications. The dielectric constant and dielectric loss of OC /BNKT film decreased obviously with increasing frequency. However, the ferroelectric state of the BNKT and its correlation with structure verified the existence of a relaxer behavior to this ratio. OC film with 20% dopped BNKT displayed energetic bactericidal activity against Gram-positive and Gram-negative bacteria. The presented study suggested that this film can be used as an antibacterial packaging material to diminish packaging's adverse environmental impacts with non-cytotoxicity. [Display omitted] [ABSTRACT FROM AUTHOR]