One-pot synthesis of cellulose / silver nanoparticle fibers and their antibacterial application

A simple, novel method was developed for synthesizing cellulose (CE) fibers doped with silver nanoparticles (Ag NPs) in the green solvent tetrabutylammonium hydroxide / dimethyl sulfoxide / H2O at room temperature. Tetrabutylammonium hydroxide accelerated the reduction of Ag+ to Ag by the cellulose chains, yielding Ag NPs in cellulose solution stabilized using polyethyleneimine (PEI). After 24 h, almost all the Ag+ was reduced to Ag NPs. The influences of silver nitrate concentration, reaction time, and stabilizer on the formation of Ag NPs were investigated by UV-vis spectrophotometry. The prepared smooth and dense cellulose / Ag NP fibers showed high mechanical properties, with a tensile strength of 304.3 MPa and an elongation at break of 22.1%. The fibers exhibited excellent antibacterial activities against Escherichia coli and Staphylococcus aureus, with more than 99% of E. coli bacteria killed by Ag NP / cellulose fibers. The synthesis procedure offers a general and mild approach to designing materials of almost any shape.

Download Full-text

A One-Pot Synthesis and Characterization of Antibacterial Silver Nanoparticle–Cellulose Film

Polymers ◽

10.3390/polym12020440 ◽

2020 ◽

Vol 12 (2) ◽

pp. 440 ◽

Cited By ~ 1

Author(s):

Qi-Yuan Chen ◽

Sheng-Ling Xiao ◽

Sheldon Q. Shi ◽

Li-Ping Cai

Keyword(s):

Composite Film ◽

Food Packaging ◽

Antibacterial Activities ◽

Light Transmittance ◽

Ag Nps ◽

One Pot ◽

One Pot Synthesis ◽

The One

Using N,N-dimethylacetamide (DMAc) as a reducing agent in the presence of PVP-K30, the stable silver nanoparticles (Ag-NPs) solution was prepared by a convenient method for the in situ reduction of silver nitrate. The cellulose–Ag-NPs composite film (CANF) was cast in the same container using lithium chloride (LiCl) giving the Ag-NPs-PVP/DMAc solution cellulose solubility as well as γ-mercaptopropyltrimethoxysilane (MPTS) to couple Ag-NPs and cellulose. The results showed that the Ag-NPs were uniformly dispersed in solution, and the solution had strong antibacterial activities. It was found that the one-pot synthesis allowed the growth of and cross-linking with cellulose processes of Ag-NPs conducted simultaneously. Approximately 61% of Ag-NPs was successfully loaded in CANF, and Ag-NPs were uniformly dispersed in the surface and internal of the composite film. The composite film exhibited good tensile properties (tensile strength could reach up to 86.4 MPa), transparency (light transmittance exceeds 70%), thermal stability, and remarkable antibacterial activities. The sterilization effect of CANF0.04 against Staphylococcus aureus and Escherichia coli exceed 99.9%. Due to low residual LiCl/DMAc and low diffusion of Ag-NPs, the composite film may have potential for applications in food packaging and bacterial barrier.

Download Full-text

Structure-activity relationships of 3-substituted-5,5- diphenylhydantoins as potential antiproliferative and antimicrobial agents

Journal of the Serbian Chemical Society ◽

10.2298/jsc110314143t ◽

2011 ◽

Vol 76 (12) ◽

pp. 1597-1606 ◽

Cited By ~ 9

Author(s):

Nemanja Trisovic ◽

Bojan Bozic ◽

Ana Obradovic ◽

Olgica Stefanovic ◽

Snezana Markovic ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antimicrobial Agents ◽

Human Colon ◽

Antibacterial Activities ◽

E Coli ◽

Structure Activity Relationships ◽

Structure Activity ◽

Almost All

A series of twelve 3-substituted-5,5-diphenylhydantoins was synthesized, including some whose anticonvulsant activities have already been reported in the literature. Their antiproliferative activities against HCT-116 human colon carcinoma cells were evaluated to determine structure-activity relationships. Almost all of the compounds exhibited statistically significant antiproliferative effects at a concentration of 100 ?M, while the derivative bearing a benzyl group was active even at lower concentrations. Moreover, their in vitro antibacterial activities against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923 and clinical isolates of Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Enterococcus faecalis and Staphylococcus aureus were evaluated. Only the 3-iso-propyl and 3-benzyl derivatives showed weak antibacterial activities against the Gram-positive bacterium E. faecalis and the Gram-negative bacteria E. coli ATCC 25922 and E. coli.

Download Full-text

Antibacterial Nanocomposites Based on Fe3O4–Ag Hybrid Nanoparticles and Natural Rubber-Polyethylene Blends

International Journal of Polymer Science ◽

10.1155/2016/7478161 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 13

Author(s):

Thanh Dung Ngo ◽

Thi My Hanh Le ◽

The Huu Nguyen ◽

Thien Vuong Nguyen ◽

Tuan Anh Nguyen ◽

...

Keyword(s):

Antibacterial Activity ◽

Natural Rubber ◽

Antibacterial Activities ◽

Hybrid Nanoparticles ◽

Growth Phases ◽

Elongation At Break ◽

E Coli ◽

Gram Positive Bacteria ◽

Polyethylene Blends ◽

Internal Mixer

For the vulcanized natural rubber (NR), incorporation of silver nanoparticles (AgNPs) into the NR matrix did not exhibit the bactericidal property against Escherichia coli (E. coli). However, incorporation of AgNPs into polyethylene (PE) matrix showed good antibacterial activities to both Gram-negative and Gram-positive bacteria. In the present work, NR/PE (85/15) blends have been prepared by melt blending with presence of compatibilizer in an internal mixer. To possess antibacterial property, AgNPs (5–10 nm) or Fe3O4–Ag hybrid nanoparticles (FAgNPs, 8 nm/16 nm) were added into PE matrix before its blending with NR component. The tensile test indicated that the presence of compatibilizer in NR/PE blend significantly enhanced the tensile strength and elongation at break (up to 35% and 38% increases, resp.). The antibacterial activity test was performed by monitoring of the bacterial lag-log growth phases with the presence of nanocomposites in the E. coli cell culture reactor. The antibacterial test showed that the presence of FAgNPs in NR/PE blend had a better antibacterial activity than that obtained with the lone AgNPs. Two similar reasons were proposed: (i) the faster Ag+ release rate from the Fe3O4–Ag hybrid nanoparticles due to the electron transfer from AgNP to Fe3O4 nanoparticle and (ii) the fact that the ionization of AgNPs in hybrid nanostructure might be accelerated by Fe3+ ions.

Download Full-text

Facile synthesis of 1.3 nm monodispersed Ag nanoclusters in an aqueous solution and their antibacterial activities for E. coli

RSC Advances ◽

10.1039/c8ra04387f ◽

2018 ◽

Vol 8 (53) ◽

pp. 30207-30214 ◽

Cited By ~ 1

Author(s):

Chengpeng Jiao ◽

Yuantao Pei ◽

Liqiong Wang ◽

Haijun Zhang ◽

Zili Huang ◽

...

Keyword(s):

Aqueous Solution ◽

Antibacterial Activities ◽

Facile Synthesis ◽

One Pot ◽

E Coli ◽

Ag Nanoclusters ◽

Ag Ncs

Ag NCs of 1.3 nm prepared by a facile one-pot strategy exhibit excellent antibacterial activities for E. coli.

Download Full-text

One Pot Green Synthesis of Gold Nanoparticles Using Piper Betle Leaf Extract and their Antibacterial Activities

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1163.106 ◽

2021 ◽

Vol 1163 ◽

pp. 106-116

Author(s):

Harekrishna Bar

Keyword(s):

Gold Nanoparticles ◽

Leaf Extract ◽

Antibacterial Activities ◽

Diffusion Method ◽

Piper Betle ◽

Metallic State ◽

Antibacterial Drug ◽

One Pot ◽

Stabilizing Agents ◽

E Coli

Gold nanoparticles have been successfully synthesized using aqueous leaf extract of Piper betle In this extracellular synthesis, after exposing of metal ions to betel leaf extract, reduction leads into their metallic state and these are stabilized by the biomolecules present in leaf extract, where extract are being used as both reducing as well as stabilizing agents at ambient condition. Gold (AuNPs) nanoparticles are characterized by UV-Vis, FESEM, HRTEM and XRD measurements. Synthesized gold nanoparticles are mostly spherical in shape with diameter ~ 30-50 nm. Antibacterial activities of the synthesized nanoparticles are investigated against two Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and two Gram-positive (Staphylococcus aureus and Bacillus thuringiensis) bacteria using the disc diffusion method. AuNPs show inhibition activity against P. aeruginosa andE. coli respectively nearly equivalent to the commercially available antibacterial drug e.g. Norfloxacin (Nx). The minimum inhibition concentration (MIC) results indicate that 36 μg/mL gold nanoparticles inhibit the growth of E. coli cells.

Download Full-text

One-Pot Synthesis of SiO2@Ag Mesoporous Nanoparticle Coating for Inhibition of Escherichia coli Bacteria on Various Surfaces

Nanomaterials ◽

10.3390/nano11020549 ◽

2021 ◽

Vol 11 (2) ◽

pp. 549

Author(s):

Sukhbayar Gankhuyag ◽

Dong Sik Bae ◽

Kyoung Lee ◽

Seunghyun Lee

Keyword(s):

Escherichia Coli ◽

Antibacterial Activity ◽

High Surface ◽

High Surface Area ◽

Volume Ratio ◽

Impregnation Method ◽

Ag Nps ◽

One Pot ◽

E Coli ◽

Escherichia Coli Bacteria

Silver nanoparticles (Ag NPs) as antibacterial agents are of considerable interest owing to their simplicity, high surface area to volume ratio, and efficient oligodynamic properties. Hence, we investigated the synthesis of silica-supported Ag NPs (SiO2@Ag) as an effective antibacterial agent by using a wet-impregnation method. The formation of SiO2@Ag with Ag NP (5–15 nm diameter) on the silica particle (100–130 nm diameter) was confirmed with transmission electron microscopy (TEM). The study on antibacterial activity was performed in a liquid culture to determine the minimum inhibitory concentration (MIC) against Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) bacteria. Both bacteria are chosen to understand difference in the effect of Ag NPs against Gram-negative (E. coli) and Gram-positive (B. subtilis) bacteria. SiO2@Ag mesoporous nanoparticles had excellent antibacterial activity against E. coli bacteria and fully restricted the bacterial growth when the material concentration was increased up to 1.00 mg/mL. In addition, the obtained material had good adhesion to both steel and polyethylene substrates and exhibited a high inhibition effect against E. coli bacteria.

Download Full-text

Flow Chemistry Controls Both Self-Assembly and the Entrapped Oscillatory Cargo in Belousov-Zhabotinsky Driven Polymerization-Induced Self-Assembly

10.26434/chemrxiv.7895891 ◽

2019 ◽

Author(s):

Liman Hou ◽

Marta Dueñas-Diez ◽

Rohit Srivastava ◽

Juan Perez-Mercader

Keyword(s):

Self Assembly ◽

Flow Chemistry ◽

Batch Reactors ◽

Equilibrium Conditions ◽

One Pot ◽

Bz Reaction ◽

Polymer Vesicles ◽

Simultaneous Control ◽

Novel Method ◽

Continuously Stirred Tank Reactor

Belousov-Zhabotinsky (B-Z) reaction driven polymerization-induced self-assembly (PISA), or B-Z PISA, is a novel method for the autonomous one-pot synthesis of polymer vesicles from a macroCTA (macro chain transfer agent) and monomer solution (“soup”) containing the above and the BZ reaction components. In it, the polymerization is driven (and controlled) by periodically generated radicals generated in the oscillations of the B-Z reaction. These are inhibitor/activator radicals for the polymerization. Until now B-Z PISA has only been carried out in batch reactors. In this manuscript we present the results of running the system using a continuously stirred tank reactor (CSTR) configuration which offers some interesting advantages.Indeed, by controlling the CSTR parameters we achieve reproducible and simultaneous control of the PISA process and of the properties of the oscillatory cargo encapsulated in the resulting vesicles. Furthermore, the use of flow chemistry enables a more precise morphology control and chemical cargo tuning. Finally, in the context of biomimetic applications a CSTR operation mimics more closely the open non-equilibrium conditions of living systems and their surrounding environments.

Download Full-text

The Characterization of Antibiotic Resistance of Bacterial Isolates from Intensive Care Unit Patient Samples in a University Affiliated Hospital in Romania

Revista de Chimie ◽

10.37358/rc.19.5.7214 ◽

2019 ◽

Vol 70 (5) ◽

pp. 1778-1783

Author(s):

Andreea-Loredana Golli ◽

Floarea Mimi Nitu ◽

Maria Balasoiu ◽

Marina Alina Lungu ◽

Cristiana Cerasella Dragomirescu ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Antibiotic Resistance ◽

Bacterial Pathogens ◽

Resistance Rate ◽

Resistance Pattern ◽

Bacterial Isolates ◽

E Coli ◽

Acinetobacter Spp ◽

Almost All ◽

Klebsiella Spp

To determine the resistance pattern of bacterial pathogens involved in infections of the patients aged between 18-64 years, admitted in a ICU from a 1518-bed university-affiliated hospital. A retrospective study of bacterial pathogens was carried out on 351 patients aged between 18-64 years admitted to the ICU, from January to December 2017. In this study there were analysed 469 samples from 351 patients (18-64 years). A total of 566 bacterial isolates were obtained, of which 120 strains of Klebsiella spp. (35.39%%), followed by Nonfermenting Gram negative bacilli, other than Pseudomonas and Acinetobacter (NFB) (75- 22.12%), Acinetobacter spp. (53 - 15.63%), Pseudomonas aeruginosa and Proteus (51 - 15.04%), and Escherichia coli (49 - 14.45%). The most common isolates were from respiratory tract (394 isolates � 69.61%). High rates of MDR were found for Pseudomonas aeruginosa (64.70%), MRSA (62.65%) and Klebsiella spp. (53.33%), while almost all of the isolated NFB strains were MDR (97.33%). There was statistic difference between the drug resistance rate of Klebsiella and E. coli strains to ceftazidime and ceftriaxone (p[0.001), cefuroxime (p[0.01) and to cefepime (p[0.01). The study revealed an alarming pattern of antibiotic resistance in the majority of ICU isolates.

Download Full-text

One-pot Synthesis of Pyrazolone Sulfones by Iodine-catalyzed Sulfenylation of Pyrazolones with Aryl Sulfonyl Hydrazides Followed by Oxidation in Water

Current Organic Synthesis ◽

10.2174/1570179414666171020113745 ◽

2018 ◽

Vol 15 (3) ◽

pp. 380-387

Author(s):

Xia Zhao ◽

Xiaoyu Lu ◽

Lipeng Zhang ◽

Tianjiao Li ◽

Kui Lu

Keyword(s):

Double Bond ◽

Efficient Method ◽

Room Temperature ◽

Sulfonyl Chloride ◽

Antibacterial Activities ◽

Oxidation Reactions ◽

Reaction Conditions ◽

One Pot ◽

X Ray ◽

Amide Form

Aim and Objective: Pyrazolone sulfones have been reported to exhibit herbicidal and antibacterial activities. In spite of their good bioactivities, only a few methods have been developed to prepare pyrazolone sulfones. However, the substrate scope of these methods is limited. Moreover, the direct sulfonylation of pyrazolone by aryl sulfonyl chloride failed to give pyrazolone sulfones. Thus, developing a more efficient method to synthesize pyrazolone sulfones is very important. Materials and Method: Pyrazolone, aryl sulphonyl hydrazide, iodine, p-toluenesulphonic acid and water were mixed in a sealed tube, which was heated to 100°C for 12 hours. The mixture was cooled to 0°C and m-CPBA was added in batches. The mixture was allowed to stir for 30 min at room temperature. The crude product was purified by silica gel column chromatography to afford sulfuryl pyrazolone. Results: In all cases, the sulfenylation products were formed smoothly under the optimized reaction conditions, and were then oxidized to the corresponding sulfones in good yields by 3-chloroperoxybenzoic acid (m-CPBA) in water. Single crystal X-ray analysis of pyrazolone sulfone 4aa showed that the major tautomer of pyrazolone sulfones was the amide form instead of the enol form observed for pyrazolone thioethers. Moreover, the C=N double bond isomerized to form an α,β-unsaturated C=C double bond. Conclusion: An efficient method to synthesize pyrazolone thioethers by iodine-catalyzed sulfenylation of pyrazolones with aryl sulfonyl hydrazides in water was developed. Moreover, this method was employed to synthesize pyrazolone sulfones in one-pot by subsequent sulfenylation and oxidation reactions.

Download Full-text

Antimicrobial Efficacy and Spectrum of Phosphorous-Fluorine Co-Doped TiO2 Nanoparticles on the Foodborne Pathogenic Bacteria Campylobacter jejuni, Salmonella Typhimurium, Enterohaemorrhagic E. coli, Yersinia enterocolitica, Shewanella putrefaciens, Listeria monocytogenes and Staphylococcus aureus

Foods ◽

10.3390/foods10081786 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1786

Author(s):

György Schneider ◽

Bettina Schweitzer ◽

Anita Steinbach ◽

Botond Zsombor Pertics ◽

Alysia Cox ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Campylobacter Jejuni ◽

Food Industry ◽

Pathogenic Bacteria ◽

Antibacterial Activities ◽

Tio2 Nps ◽

E Coli ◽

Foodborne Pathogenic Bacteria ◽

And Staphylococcus Aureus ◽

Co Doped

Contamination of meats and meat products with foodborne pathogenic bacteria raises serious safety issues in the food industry. The antibacterial activities of phosphorous-fluorine co-doped TiO2 nanoparticles (PF-TiO2) were investigated against seven foodborne pathogenic bacteria: Campylobacter jejuni, Salmonella Typhimurium, Enterohaemorrhagic E. coli, Yersinia enterocolitica, Shewanella putrefaciens, Listeria monocytogenes and Staphylococcus aureus. PF-TiO2 NPs were synthesized hydrothermally at 250 °C for 1, 3, 6 or 12 h, and then tested at three different concentrations (500 μg/mL, 100 μg/mL, 20 μg/mL) for the inactivation of foodborne bacteria under UVA irradiation, daylight exposure or dark conditions. The antibacterial efficacies were compared after 30 min of exposure to light. Distinct differences in the antibacterial activities of the PF-TiO2 NPs, and the susceptibilities of tested foodborne pathogenic bacterium species were found. PF-TiO2/3 h and PF-TiO2/6 h showed the highest antibacterial activity by decreasing the living bacterial cell number from ~106 by ~5 log (L. monocytogenes), ~4 log (EHEC), ~3 log (Y. enterolcolitca, S. putrefaciens) and ~2.5 log (S. aureus), along with complete eradication of C. jejuni and S. Typhimurium. Efficacy of PF-TiO2/1 h and PF-TiO2/12 h NPs was lower, typically causing a ~2–4 log decrease in colony forming units depending on the tested bacterium while the effect of PF-TiO2/0 h was comparable to P25 TiO2, a commercial TiO2 with high photocatalytic activity. Our results show that PF-co-doping of TiO2 NPs enhanced the antibacterial action against foodborne pathogenic bacteria and are potential candidates for use in the food industry as active surface components, potentially contributing to the production of meats that are safe for consumption.

Download Full-text