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•Ag NWs@BaTiO3 core–shell composite containing twin crystals, heterojunctions, and piezoelectric properties has been fabricated.•Ag NWs@BaTiO3 exhibits an excellent synergistic ...piezo-photocatalytic degradation performance, demonstrating an extended charge transfer pathway and accelerated excitation-charge pair separation efficiency.•Ag NWs@BaTiO3 maintains a high sono-photodynamic antibacterial (Staphylococcus aureus and Escherichia coli) activity, good biocompatibility, and low cytotoxicity.•A coupling piezo-photocatalysis mechanism is conducted over Ag NWs@BaTiO3.
Sono-photodynamic antibacterial therapy (SPDAT) is considered to be one of the most effective biomedical treatments, offering both practical flexibility and excellent performance. However, sono-photosensitizers with good biocompatibility, low cytotoxicity, and high antibacterial efficiency under harsh conditions are lacking nowadays. This paper presented attractive Ag NWs@BaTiO3 core–shell composites, which integrates three elements of piezoelectric effect, twin crystals, and heterojunction to engineer triple internal electric fields. Continuous co-disturbances induced by ultrasound and light disrupted the electrostatic balance and saturation effects of the triple internal electric field on composites, thereby regulating its own electrical properties and increasing its affinity and adhesion to bacterial cells through electrostatic attraction. Remarkably, the antibacterial efficiency of Ag NWs@BaTiO3 against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) reached 92.5% within 60 min and ∼ 100% within 30 min under low-power visible light irradiation and ultrasonic vibration, respectively. Moreover, the composites also exhibited good biocompatibility and low cytotoxicity. Intrinsically, the constructed triple internal electric fields could effectively extend the charges transfer pathway, accelerating the spatial separation of excited-charges pairs and thereby producing sufficient reactive oxygen species (ROSs) to boost the synergistic piezo-photocatalysis activity. Finally, we proposed a combined piezo-photocatalysis mechanism of energy band bending theory and screening charge effect under triple internal electric fields.
•Ag2O doped bioactive glasses were synthesized by melt-quench method.•Antibacterial zone of inhibition was increased with addition of Ag2O.•Optical band gap (Eopt) was decreased with Ag2O ...content.•IR, Raman studies revealed the modifier role of Ag2O in the glasses.•Conductivity and biological activity enhanced with NBOs.
Bioactive novel glasses of chemical composition xAg2O-20Li2O-25TeO2-(55-x) B2O3 (0 ≤ x ≤ 2 mol%) were synthesized through the melt-quench method and investigated the influence of Ag2O on various properties. The antibacterial properties of the obtained glasses were studied against two gram negative bacterial strains like Salmonella and E. Coli. (E. Coli.) species and the antibacterial zone of inhibition was increased with increasing Ag2O. The density (ρ) of the glasses increased from 3.60 to 3.83 g/cm3 with the addition of Ag2O. UV–Vis. absorption spectrum of the glass system was recorded and estimated the cut-off wavelength (λc), the optical band gap energies (Eopt), the Urbach energy (ΔE), the refractive index etc. FT-IR and Raman spectroscopic studies revealed the existence and impact of the modifier Ag2O. Impedance study revealed that the NBOs play significant role in the enhancement of the ionic conductivity and also causing the enhancement of antibacterial efficiency.
Silver doped diamond-like carbon (DLC) films were prepared on Si (111) substrates by dual-targets high power impulse magnetron sputtering (HiPIMS), and the chemical composition, microstructure, ...mechanical properties and antibacterial properties of the as-deposited films were obtained. When the sputtering voltage of the Ag target was varied from 450 to 580 V, X-ray photoelectron spectroscopy results revealed that the concentration of Ag in the as-deposited films was increased from 19.1 to 32.0 at. %. High resolution transmission electron microscopy images depicted that the as-deposited films were composed of Ag nanoparticles (AgNPs) embedded in DLC matrix. Along the cross-section of the film, the size of silver nanocrystals was varied from 5–12 (in the middle) to 2–5 nm (in the top surface). When the sputtering voltage was increased, the density of AgNPs was raised also. In addition, when the bias was increased from −50 to −100 V, the size of AgNPs in the top surface was reduced from 5–12 to 2–5 nm. AgNPs with a small size benefited the release of silver ions and improved the antibacterial ability, and the samples fabricated with the sputtering voltage (Ag target) of 500–560 V and a larger bias (-100 V) obtained an excellent antibacterial efficiency (> 99.5%) against Escherichia coli and Staphylococcus aureus.
•Ag-DLC films were fabricated by dual-targets high power impulse magnetron sputtering (HiPIMS).•Smaller AgNPs could be get simultaneously when increasing the silver concentration and the particle size of AgNPs in the top surface could be reduced to 2–5 nm by applying a higher bias of -100 V.•An excellent antibacterial efficiency (>99.5%) was obtained by enhancing the Ag+ release, resulted from the decreasing particle size of AgNPs.
•RuO2/IrO2 shows outstanding dual enzyme-mimic activities and excellent bactericidal activity.•RuO2/IrO2 exhibited good biocompatibility and high biosafety.
The increasing bacterial resistance caused ...by the abuse of antibiotics has become an urgent global healthcare challenge. Recent advances in nanozymes represent one feasible solution. However, efforts have mainly focused on mimicking natural enzymes for comparable biocatalytic activities, as preparing nanozymes with superior antibacterial properties remains challenging. In this study, inspired by the Fe catalytic site in horseradish peroxidase (HRP), we synthesized defect-rich ruthenium oxide/iridium oxide heterojunction nanosheets (RuO2/IrO2), using Ru, which possesses a similar electronic structure to Fe, as the catalytic site to enhance antibacterial properties. Benefiting from the typically high catalytic activity of Ru in various reactions and the unique Ir-mediated defect-rich heterostructure, RuO2/IrO2 exhibits dramatically enhanced biocatalytic activities in generating reactive oxygen species crucial for eradicating bacteria. In particular, RuO2/IrO2 exhibited both oxidase and peroxidase-mimicking activities with catalytic efficiency 103 to 104 times higher than that of HRP. It exhibited superior antibacterial properties as well as high biosafety, effectively eliminating H2O2 toxicity during in vivo anti-infection measures. Minimum inhibitory concentration (MIC) values of RuO2/IrO2 against Staphylococcus aureus and Escherichia coli were 31.25 and 15.62 μg mL−1, respectively. This study offers a promising potential design for antibacterial nanozymes.
Poly(vinyl chloride) (PVC) was loaded with various contents of Moringa oleifera (MO) leaves extract. The changes in the structure arising after loading MO into the polymeric matrix were monitored. In ...addition, their rheological and mechanical properties were investigated. Some thermal analyses techniques were performed to demonstrate any change in the thermal stability of PVC before and after adding MO. PVC/MO exhibited noticeable antibacterial efficiency when evaluated against Gram‐positive and Gram‐negative bacteria. A favorable antibacterial efficiency of PVC/MO boosted with increasing of MO content from 5% to 25% by weight when introduced into PVC. The photostability of PVC enriched with MO was investigated. The change in the rate of dehydrochlorination for PVC was detected. It was indicated with liberating HCl from the polymeric matrix.
Self-assembled functional nanomaterials with electromagnetic hot spots are crucial and highly desirable in surface-enhanced Raman scattering (SERS). Due to its versatile biological scaffold, the M13 ...phage has been employed to produce novel nano-building blocks and devices. In this study, we propose a novel M13 phage-based SERS nanocarrier, that utilizes the pVIII capsid in M13 to conjugate Au@Ag core-shell nanorod (Au@AgNR) with linker carboxy-PEG-thiol (M13-Au@AgNR) and the pIII capsid to specifically target Escherichia coli (E. coli). The M13-Au@AgNR@DTTC (3,3′- diethylthiocarbocyanine iodide) SERS probe was used to detect E. coli in a concentration range of 6 to 6 × 105 cfu/mL, achieving a limit of detection (LOD) of 0.5 cfu/mL. The proposed SERS platform was also tested in real samples, showing good recoveries (92%–114.3%) and a relative standard deviation (RSD) of 1.2%–4.7%. Furthermore, the system demonstrated high antibacterial efficiency against E. coli, approximately 90%, as measured by the standard plate-count method. The investigation provides an effective strategy for in vitro bacteria detection and inactivation.
•CaO doped antimony lithium borate glasses were synthesized by melt-quench method.•Antibacterial efficiency was found maximum for high CaO mole fraction.•AC Conductivity enhanced with NBOs and Li+ ...ions up to 10−2Ω−1cm−1order.•Optical band gap (Eopt) was decreased with CaO content.
The antimicrobial efficiency, structural, optical, and electric transport properties of glasses of composition xCaO.10Li2O.20Sb2O3.(70-x)B2O3 (x = 0,2.5,5,7.5 and 10 mol%) and the role of CaO have been studied in this work. The amorphous phase of the glasses was confirmed through an X-ray diffraction study. The optical bandgap energy (Eopt) was decreased with the addition of CaO, whereas, the refractive index values were increased. Urbach energy (∆E) of the glasses varied from 0.32 to 0.48 eV. Density (ρ) of the studied glasses was found to increase from 3.38 g/cm3 to 3.77 g/cm3 with CaO content. Antibacterial efficiency of the glasses was examined through a well plate method against Escherichia Coli., Salmonella in terms of zone of inhibition and it is increasing with CaO content. Glass transition temperature (Tg) was decreased with increasing CaO content. NBOs play an significant role in achieving the higher order ionic conductivity. Due to the presence of Li2O, Cole-Cole impedance plots exhibited semicircular behavior at high temperatures. FT-IR studies confirms the vibrations of B-O, B-O-B with B-O-Sb linkages in the glass.
The study was focused on the usability of olive tree leaves fallen during olive harvesting in dyeing and antibacterial finishing of cotton fabrics for cleaner production. Valorizing these waste ...(olive tree leaves) obtained during harvesting and using them in textile treatment processes would ensure a cleaner and more sustainable production. For this aim, olive tree leaves were subjected to an extraction process before their use in dyeing as well as directly use without any previous extraction. Six mordanting agents were also tested. Dyeing was done at two different temperatures (80°C and 100°C), and the liquor ratio was 1:60. First, the treated samples were tested for fastness and color variety. It was observed that sufficient fastness and color variety can be produced by using olive tree leaves with or without mordanting agents. Antibacterial tests were also conducted for samples dyed without mordanting agents. The antibacterial effects of mordants were also tested. The samples were tested against Escherichia coli and Staphylococcus aureus. It was found that mordanting agents provide significant antibacterial efficiency against both tested bacteria and minimum of 90% bacterial reduction was observed. Using olive tree leaves without any mordants also demonstrated antibacterial efficiency and better bacterial reductions were observed for both bacterial species in dyeings at 80°C. The reason of antibacterial efficiency caused by the olive tree leaves were investigated by ICP-MS analysis. Addition to the oleuropein content of the extract, the elements detected by ICP-MS assumed as responsible for the bacterial reduction.
•Waste “olive tree leaves” come out during harvesting can be used as a source of natural dyeing.•The combination olive tree leaves with metal salts (mordant) in dyeing of cotton can serve for alteration of the colors.•Dyeing of cotton with the extract from olive tree leaves at low temperature can serve for antibacterial activity.•The processing with mordants can ensure antibacterial activity in the cotton fabrics.
•Preparation of CAgMs with controllable size was successfully developed.•The optimal bacteriostatic CAgMs was successfully prepared.•The size depending bacteriostasis function of CAgMs was fully ...proved and theorized.
The control of chitosan/silver nanoparticle composite microsphere (CAgMs) size is crucial for tuning its function. In the current work, monodisperse organically-modified CAgMs with controllable size were synthesized using a two-step method. The fine-tuning of the microsphere size was confirmed by many reaction parameters while the cross-linking agent was the key research object. Through physical and thermodynamic analysis, we found the cross-linking agent-induced smaller size, higher silver concentration, more heightened glass transition temperature and stronger hydrogen bond network. The as-prepared microspheres exhibited strong bacteriostasis and fresh-keeping function depending on cross-linking agent concentration. The phenomenon is believed to be derived from the difference in microorganism adsorption and killing ability from induced varying specific surface area and encapsulated silver content. Our current work highlights the size-controllable preparation of CAgMs, and based on our findings, small size CAgMs can be a promising candidate in the field of antibacterial and fruit preservation applications.
In this study, a novel nanofiber with improved antibacterial efficiencies was created by introducing TiO2 nanofibers and graphene oxide (GO) sheets into cellulose acetate (CA) nanofibers using an ...efficient electrospinning process. The morphologies and chemical composition of above nanocomposite were fully measured by SEM, FTIR and XRD measurements. The results demonstrated that TiO2 nanofibers and GO sheets have a uniform distribution in the CA nanofibers and these two additives also could improve hydrophilicity. TiO2/GO/CA@cotton exhibited high antibacterial activity with an inhibition rate higher than 95% against B. subtilis and B. cereus bacteria. Therefore, the proposed nanofiber is promising for the large-scale production of antibacterial nanofiber/cotton hybrid yarns for biomedical and antibacterial textiles applications.
•TiO2 and GO embedded CA nanofibers were facilely fabricated.•Electrospinning is performed to fabricate antibacterial nanofibers.•Hydrophilicity and antibacterial properties have been effectively improved.
