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Small (Weinheim An Der Bergstrasse,... Jun 2024The development of wearable thermoelectric generators (wTEG) represents a promising strategy to replace batteries and supercapacitors required to supply electrical...
The development of wearable thermoelectric generators (wTEG) represents a promising strategy to replace batteries and supercapacitors required to supply electrical energy for portable electronic devices. However, the main drawback of wTEGs is that the thermal gradient between the skin and the ambient is minimal, reducing the power output produced by the generator. Therefore, it is necessary to improve the thermal management of wTEG in order to increase its efficiency. This work deals with the preparation of a thermoelectric generator that harnesses the plasmonic heating effect to enhance the thermal gradient of the final device. The thermoelectric layer is created through the in situ polymerization of terthiophene (3T) within a polyurethane matrix, utilizing silver (Ag) (I) and copper (II) perchlorate as oxidants. The plasmonic film, composed of Ag-NP (nanoparticles), is formed via photocatalytic reduction of silver nitrate in the presence of titanium oxide. These layers are then meticulously assembled to yield the hybrid plasmonic/thermoelectric generator.
PubMed: 38830337
DOI: 10.1002/smll.202400345 -
ACS Omega May 2024A fluorosulfate ion (FSO) is a hydrolysis product of sulfuryl fluoride (SOF), which is widely used to fumigate buildings, soil, construction materials, and postharvest...
A fluorosulfate ion (FSO) is a hydrolysis product of sulfuryl fluoride (SOF), which is widely used to fumigate buildings, soil, construction materials, and postharvest commodities, and is a potent greenhouse gas. It is a potential marker for biological exposure to SOF and for monitoring the progress of reactions used to scrub SOF from fumigation vent gases. Here, we report a simple and inexpensive potentiometric method for determining FSO using a commercial nitrate-selective electrode and discuss its application. The method is suitable for solutions between 0.0025 mM and 660 mM FSO at initial pH between 5 and 9. Halide interference depends on its molar ratio to FSO and follows the sequence, F < Cl < Br ≪ I. Halide interference can be eliminated by adding silver sulfate. Interference by bicarbonate can be eliminated by HSO pretreatment, and interference by phosphate or pyrophosphate by MgSO addition. Sulfate does not interfere, as it does in ion chromatography. Satisfactory method detection limits for FSO in spiked aqueous extracts of 11 fruits were obtained. The method accurately quantified the yield of FSO relative to that of F in base hydrolysis of SOF. This study demonstrates that the developed method is highly selective, convenient, and sensitive and thus can be of great value in practice.
PubMed: 38826532
DOI: 10.1021/acsomega.4c02629 -
Scientific Reports May 2024Cassava root rot disease caused by the fungal pathogens Fusarium solani and Lasiodiplodia theobromae produces severe damages on cassava production. This research was...
Cassava root rot disease caused by the fungal pathogens Fusarium solani and Lasiodiplodia theobromae produces severe damages on cassava production. This research was conducted to produce and assess silver nanoparticles (AgNPs) synthesized by Trichoderma harzianum for reducing root rot disease. The results revealed that using the supernatants of T. harzianum on a silver nitrate solution changed it to reddish color at 48 h, indicating the formation of AgNPs. Further characterization was identified using dynamic light scattering (DLS) and scanning electron microscope (SEM). DLS supported that the Z-average size is at 39.79 nm and the mean zeta potential is at - 36.5 mV. SEM revealed the formation of monodispersed spherical shape with a diameter between 60-75 nm. The antibacterial action of AgNPs as an antifungal agent was demonstrated by an observed decrease in the size of the fungal colonies using an increasing concentration of AgNPs until the complete inhibition growth of L. theobromae and F. solani at > 58 µg mL and at ≥ 50 µg mL, respectively. At in vitro conditions, the applied AgNPs caused a decrease in the percentage of healthy aerial hyphae of L. theobromae (32.5%) and of F. solani (70.0%) compared to control (100%). The SR-FTIR spectra showed the highest peaks in the first region (3000-2800 cm) associated with lipids and fatty acids located at 2962, 2927, and 2854 cm in the AgNPs treated samples. The second region (1700-1450 cm) consisting of proteins and peptides revealed the highest peaks at 1658, 1641, and 1548 cm in the AgNPs treated samples. The third region (1300-900 cm), which involves nucleic acid, phospholipids, polysaccharides, and carbohydrates, revealed the highest peaks at 1155, 1079, and 1027 cm in the readings from the untreated samples. Finally, the observed root rot severity on cassava roots treated with AgNPs (1.75 ± 0.50) was significantly lower than the control samples (5.00 ± 0.00).
Topics: Metal Nanoparticles; Silver; Plant Diseases; Manihot; Plant Roots; Fusarium; Antifungal Agents; Hypocreales; Trichoderma
PubMed: 38821999
DOI: 10.1038/s41598-024-60903-z -
PloS One 2024The use of plants in the biological production of silver nanoparticles for antibacterial applications is a growing field of research. In the current work, we formulated...
The use of plants in the biological production of silver nanoparticles for antibacterial applications is a growing field of research. In the current work, we formulated Ocimum kilimandscharicum extracts using silver nanoparticles, and evaluated its potential antibacterial activity. Aqueous and methanol plant extracts were used to reduce silver nitrate at different time intervals (30 to 150 minutes) and pH (2 to 11). The UV-visible absorption spectrum recorded for methanol and aqueous extracts revealed a successful synthesis of AgNPs for methanol and aqueous extracts. The antimicrobial activity of the AgNPs was evaluated against Escherichia coli ATCC 25922, Salmonella choleraesuius ATCC 10708, and Staphylococcus aureus ATCC 25923 The best inhibition zone for the methanol and aqueous-mediated AgNPs, ranging from 12 ± 1 to 16 ± 1mm. Additionally, the methanol and aqueous extract silver nanoparticles had the same Minimum Inhibitory Concentration (6.25 ± 0.00 mg/ml), whereas the Minimum Bactericidal Concentrations were 12.5 ± 0.00 and 25 ± 0.00 mg/ml, respectively. The highest inhibition zone of 16 ± 1 mm was observed against Salmonella choleraesuius with 50 ± 0.00 mg/ml aqueous silver nanoparticles. The results show that the silver nanoparticles made with Ocimum kilimandscharicum have antibacterial action against those microorganisms.
Topics: Plant Extracts; Anti-Bacterial Agents; Silver; Metal Nanoparticles; Ocimum; Plant Leaves; Microbial Sensitivity Tests; Staphylococcus aureus; Escherichia coli; Bacteria
PubMed: 38809950
DOI: 10.1371/journal.pone.0295463 -
Heliyon May 2024is an opportunistic phytopathogen that negatively impact the growth and production of a wide variety of host plants. In this study, we evaluated the antifungal...
is an opportunistic phytopathogen that negatively impact the growth and production of a wide variety of host plants. In this study, we evaluated the antifungal potential of biogenic ZnO, and bimetallic silver and zinc oxide (Ag/ZnO) nanoparticles synthesized using seed extract of and characterized using different analytical tools. antifungal potentials of ZnO and Ag/ZnO nanoparticles were carried out using the food poison technique. Morphological and ultrastructure of the treated with the nanoparticles were carried out using high resolution scanning and transmission electron microscopy (HRSEM and HRTEM). In addition, changes in polysaccharide production, chitin content and enzymatic (cellulase and lipase) activities of were assayed. Double peak signifying a UV of 353.88 and 417.25 nm representing Ag and ZnO respectively was formed in the bimetallic nanoparticles. HRSEM and HRTEM results shows agglomerated nanoparticles with particle and crystallite size of 23.94 and 16.84 nm for ZnO nanoparticles, 35.12 and 28.99 nm for Ag/ZnO nanoparticles respectively. antifungal assay shows a significant concentration-dependent inhibition (p < 0.05) of mycelia with highest percentage inhibition of 73.93 % (ZnO nanoparticles) and 68.26 % (Ag/ZnO nanoparticles) at 200 ppm. HRSEM and HRTEM micrographs of the treated mycelia shows alteration of the cellular structure, clearance of the cytoplasmic organelles and localization of the nanoparticles within the cell. treated with 200 ppm nanoparticles show a significant decrease (p < 0.05) in the polysaccharides and chitin contents, cellulase and lipase activities. The results suggests that ZnO and Ag/ZnO nanoparticles mode of action may be via alteration of the fungal cell wall through the inhibition of polysaccharides, chitin, cellulases and lipases synthesis. ZnO and Ag/ZnO nanoparticles may be a promising tool for the management and control of disease causing fungal phytopathogens.
PubMed: 38803897
DOI: 10.1016/j.heliyon.2024.e31330 -
Pharmaceutics May 2024A general procedure to prepare gold nanourchins (GNUs) via a seed-mediated method was followed using dopamine hydrochloride as a reducing agent and silver nitrate salt...
A general procedure to prepare gold nanourchins (GNUs) via a seed-mediated method was followed using dopamine hydrochloride as a reducing agent and silver nitrate salt (AgNO) as a shape-directing agent. The novelty of this study comes from the successful incorporation of the prepared gold urchins as an aqueous suspension in a nasal pressurized metered dose inhaler (pMDI) formulation and the investigation of their potential for olfactory targeting for direct nose-to-brain drug delivery (NTBDD). The developed pMDI formulation was composed of 0.025% / GNUs, 2% / Milli-Q water, and 2% / EtOH, with the balance of the formulation being HFA134a propellant. Particle integrity and aerosolization performance were examined using an aerosol exposure system, whereas the nasal deposition profile was tested in a sectioned anatomical replica of human nasal airways. The compatibility of the gold dispersion with the nasal epithelial cell line RPMI 2650 was also investigated in this study. Colloidal gold was found to be stable following six-month storage at 4 °C and during the lyophilization process utilizing a pectin matrix for complete re-dispersibility in water. The GNUs were intact and discrete following atomization via a pMDI, and 13% of the delivered particles were detected beyond the nasal valve, the narrowest region in the nasal cavity, out of which 5.6% was recovered from the olfactory region. Moreover, the formulation was found to be compatible with the human nasal epithelium cell line RPMI 2650 and excellent cell viability was observed. The formulated GNU-HFA-based pMDI is a promising approach for intranasal drug delivery, including deposition in the olfactory region, which could be employed for NTBDD applications.
PubMed: 38794331
DOI: 10.3390/pharmaceutics16050669 -
International Journal of Molecular... May 2024Melanoma, arguably the deadliest form of skin cancer, is responsible for the majority of skin-cancer-related fatalities. Innovative strategies concentrate on new...
Melanoma, arguably the deadliest form of skin cancer, is responsible for the majority of skin-cancer-related fatalities. Innovative strategies concentrate on new therapies that avoid the undesirable effects of pharmacological or medical treatment. This article discusses the chemical structures of [(MTZ)AgNO], [(MTZ)Ag]SO, [Ag(MCZ)NO], [Ag(MCZ)BF], [Ag(MCZ)SbF] and [Ag(MCZ)ClO] (MTZ-metronidazole; MCZ-miconazole) silver(I) compounds and the possible relationship between the molecules and their cytostatic activity against melanoma cells. Molecular Hirshfeld surface analysis and computational methods were used to examine the possible association between the structure and anticancer activity of the silver(I) complexes and compare the cytotoxicity of the silver(I) complexes of metronidazole and miconazole with that of silver(I) nitrate, cisplatin, metronidazole and miconazole complexes against A375 and BJ cells. Additionally, these preliminary biological studies found the greatest IC values against the A375 line were demonstrated by [Ag(MCZ)NO] and [(MTZ)AgNO]. The compound [(MTZ)AgNO] was three-fold more toxic to the A375 cells than the reference (cisplatin) and 15 times more cytotoxic against the A375 cells than the normal BJ cells. Complexes of metronidazole with Ag(I) are considered biocompatible at a concentration below 50 µmol/L.
Topics: Humans; Melanoma; Miconazole; Silver; Antineoplastic Agents; Metronidazole; Cell Line, Tumor; Coordination Complexes; Cell Survival; Skin Neoplasms
PubMed: 38791121
DOI: 10.3390/ijms25105081 -
Bioengineering (Basel, Switzerland) May 2024Synthesis of silver nanoparticles with antibacterial properties using a one-pot green approach that harnesses the natural reducing and capping properties of cinnamon ()...
Synthesis of silver nanoparticles with antibacterial properties using a one-pot green approach that harnesses the natural reducing and capping properties of cinnamon () bark extract is presented in this work. Silver nitrate was the sole chemical reagent employed in this process, acting as the precursor salt. Gas Chromatography-Mass Spectroscopy (GC-MS), High-Performance Liquid Chromatography (HPLC) analysis, and some phytochemical tests demonstrated that cinnamaldehyde is the main component in the cinnamon bark extract. The resulting bio-reduced silver nanoparticles underwent comprehensive characterization by Ultraviolet-Vis (UV-Vis) and Fourier Transform InfraRed spectrophotometry (FTIR), Dynamic Light Scattering (DLS), Transmission Electron Microscopy, and Scanning Electron Microscopy suggesting that cinnamaldehyde was chemically oxidated to produce silver nanoparticles. These cinnamon-extract-based silver nanoparticles (AgNPs-cinnamon) displayed diverse morphologies ranging from spherical to prismatic shapes, with sizes spanning between 2.94 and 65.1 nm. Subsequently, the antibacterial efficacy of these nanoparticles was investigated against , , , , and strains. The results suggest the promising potential of silver nanoparticles obtained (AgNPs-cinnamon) as antimicrobial agents, offering a new avenue in the fight against bacterial infections.
PubMed: 38790383
DOI: 10.3390/bioengineering11050517 -
International Journal of Biological... Jun 2024With increasing concern for the environment, the demand for carbon dioxide separation, a key contributor to global warming, has escalated. Therefore, this paper focuses...
With increasing concern for the environment, the demand for carbon dioxide separation, a key contributor to global warming, has escalated. Therefore, this paper focuses on carbon dioxide separation by creating an hydroxyethyl cellulose (HEC)(CHO)*(CHO(OH))/silver tetra fluoroborate (AgBF)/aluminum nitrate (Al(NO)) composite film, demonstrating excellent separation performance with a permeance of 1.0 GPU and a selectivity of 100. Silver ions enhance the solubility of carbon dioxide, aiding in its separation, and we determined the optimal aluminum composition to stabilize the silver ions. To analyze this, we examined the cross-sections using SEM, confirming a selective layer of 1.7 μm for carbon dioxide separation. Furthermore, TGA, FT-IR, and NMR analyses were conducted to investigate the interaction between the polymer and additives. This revealed that the increased polymer chain due to the interaction between Ag and HEC, along with stabilized Ag facilitated by the addition of Al, maximized the interaction with carbon dioxide via the empty s-orbital. Additionally, SEM-EDX, UV-vis, XRD, XPS analyses were employed to elucidate the movement of ions within the membrane. These results provide insights into the performance of membranes based on cellulose polymer and offer valuable insights for future applications in gas separation technologies.
Topics: Cellulose; Carbon Dioxide; Gases; Silver; Green Chemistry Technology
PubMed: 38788883
DOI: 10.1016/j.ijbiomac.2024.132576 -
Microbial Pathogenesis Jul 2024Medicinal plants have been widely used for their antimicrobial properties against various microorganisms. Arisaema dracontium a familiar medicinal plant, was analyzed...
Exploration of reducing and stabilizing phytoconstituents in Arisaema dracontium extract for the effective synthesis of Silver nanoparticles and evaluation of their antibacterial and toxicological proprties.
Medicinal plants have been widely used for their antimicrobial properties against various microorganisms. Arisaema dracontium a familiar medicinal plant, was analyzed and silver nanoparticles (AgNPs) were synthesized using extracts of different parts of its shoot including leaves and stem. Further, the antimicrobial activity of different solvent extracts such as ethyl acetate, n-hexane, ethanol, methanol, and chloroform extracts were analyzed. AgNPs were prepared using aqueous silver nitrate solution and assessed their antibacterial activity against multidrug-resistant (MDR) and Non-multidrug-resistant bacteria. The characterization of AgNPs was done by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), UV-visible spectroscopy, Fourier Transform Infrared (FTI), and X-ray Diffraction approaches. The leaf extract contained Tannins, Flavonoids, Terpenoids, and Steroids while Alkaloids, Saponins, and Glycosides were undetected. The stem extract contained Alkaloids, Tannins, Flavonoids, Saponins, Steroids, and Glycosides while Terpenoids were not observed. The AgNPs synthesized from stem and leaf extracts in the current study had spherical shapes and ranged in size from 1 to 50 nm and 20-500 nm respectively as were visible in TEM. The leaf extract-prepared AgNPs showed significantly higher activities i.e., 27.75 mm ± 0.86 against the MDR strains as compared to the stem-derived nanoparticles i.e., 24.33 ± 0.33 by comparing the zones of inhibitions which can be attributed to the differences in their phytochemical constituents. The acute toxicity assay confirmed that no mortality was noticed when the dosage was 100 mg per kg which confirms that the confirms that the AgNPs are not toxic when used in low quantities. It is concluded that leaf extract from A. dracontium could be used against pathogenic bacteria offering economic and health benefits compared to the chemical substances.
Topics: Plant Extracts; Metal Nanoparticles; Anti-Bacterial Agents; Silver; Microbial Sensitivity Tests; Plant Leaves; Bacteria; X-Ray Diffraction; Phytochemicals; Spectroscopy, Fourier Transform Infrared; Drug Resistance, Multiple, Bacterial; Plants, Medicinal; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Plant Stems
PubMed: 38788810
DOI: 10.1016/j.micpath.2024.106711