scholarly journals The Impact of Surface Functionalization on the Biophysical Properties of Silver Nanoparticles

Nanomaterials ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 973 ◽  
Author(s):  
Agnieszka Borowik ◽  
Kamila Butowska ◽  
Kinga Konkel ◽  
Rafał Banasiuk ◽  
Natalia Derewonko ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Biological Activities ◽  
Antimicrobial Properties ◽  
Thiobarbituric Acid ◽  
Surface Modifications ◽  
Titration Calorimetry ◽  
Biophysical Properties ◽  
Atomic Force ◽  
Wide Range ◽  
The Impact

Among metal-based nanoparticles, silver nanoparticles (AgNPs) are particularly appealing because of their stability, functionality, and documented antimicrobial properties. AgNPs also offer the possibility of different surface modifications. In this work, we functionalized AgNPs with thiobarbituric acid or 11-mercaptoundecanoic acid residues to improve the nanoparticles’ biological activities. Subsequently, we assessed the physicochemical properties of newly synthesized AgNPs using a wide range of biophysical methodologies, including UV/vis and fluorescence spectroscopy, atomic force and scanning electron microscopy, and dynamic light scattering and isothermal titration calorimetry. Next, we examined the effect of nanoparticles functionalization on AgNPs mutagenicity and toxicity. Our study revealed that AgNPs’ surface modification affects nanoparticles aggregation, and also impacts nanoparticles’ interaction with model acridine mutagen ICR-191. AgNPs coated with MUA showed the most interesting interactions with tested ICR-191, slightly modulating its toxicity properties by decreasing the viability in treated cells.

scholarly journals In-Vitro Evaluation of Biological Activity of New Series of 1, 3, 4-Oxadiazole Derivatives Against Bap Gene Expression in Acinetobacter bumanni Biofilm

2021 ◽  
Vol In Press (In Press) ◽  
Author(s):  
Sedigheh Akbarnezhad Ghareh Lar ◽  
Nakisa Zarrabi Ahrabi ◽  
Yasin SarveAhrabi
Keyword(s):  
Biofilm Formation ◽  
Functional Group ◽  
Biological Activities ◽  
Antimicrobial Properties ◽  
Housekeeping Gene ◽  
Bacterial Biofilm ◽  
Wide Range ◽  
Oxadiazole Derivatives ◽  
The Impact

Background: Acinetobacter bumanni is one of the most common opportunistic pathogens in health centers that is resistant to many antibiotics due to biofilm production. 1, 3, 4-oxadiazoles have a wide range of biological activities. Objectives: The aim of this research was to examine the impact of new 1, 3, 4-oxadiazole derivatives on the expression of biofilm-associated surface protein (Bap), playing an important role in promoting the biofilm formation ability of A. baumannii strains. Methods: Derivatives of 1, 3, 4-oxadiazole were synthesized through a one-step synthesis. A. baumannii strains were identified and isolated in the laboratory. The antimicrobial properties of the synthesized materials against the isolated strains were investigated. DNA, RNA, and cDNA were extracted, and the relative expression of BAP gene in A. baumannii isolates was evaluated by real-time polymerase chain reaction. Results: The compound with methoxyphenyl functional group with MIC = 62.50 mg/mL had the best inhibitory performance among all derivatives. Also, the combination of 4i reduced the expression of the Bap gene by about 24 times, but it had no effect on the expression of the 16srRNA housekeeping gene. Conclusions: 1, 3, 4-oxadiazole derivatives, especially the methoxyphenyl functional group, act as an inhibitor of bacterial biofilm formation and have the potential to be used in the pharmaceutical and biological industries.

scholarly journals A Newfangled Collagenase Inhibitor Topical Formulation Based on Ethosomes with Sambucus nigra L. Extract

2021 ◽  
Vol 14 (5) ◽  
pp. 467
Author(s):  
Ana Henriques Mota ◽  
Inês Prazeres ◽  
Henrique Mestre ◽  
Andreia Bento-Silva ◽  
Maria João Rodrigues ◽  
...  
Keyword(s):  
Biological Activities ◽  
Scientific Evidence ◽  
Release Profile ◽  
Health Claims ◽  
Topical Formulation ◽  
Sambucus Nigra ◽  
Western Asia ◽  
Wide Range ◽  
The Impact ◽  
Over Time

Sambucus nigra L. (S. nigra) is a shrub widespread in Europe and western Asia, traditionally used in medicine, that has become popular in recent years as a potential source of a wide range of interesting bioactive compounds. The aim of the present work was to develop a topical S. nigra extract formulation based on ethosomes and thus to support its health claims with scientific evidence. S. nigra extract was prepared by an ultrasound-assisted method and then included in ethosomes. The ethosomes were analyzed in terms of their size, stability over time, morphology, entrapment capacity (EC), extract release profile, stability over time and several biological activities. The prepared ethosomes were indicated to be well defined, presenting sizes around 600 nm. The extract entrapment capacity in ethosomes was 73.9 ± 24.8%, with an interesting slow extract release profile over 24 h. The extract-loaded ethosomes presented collagenase inhibition activity and a very good skin compatibility after human application. This study demonstrates the potential use of S. nigra extract incorporated in ethosomes as a potential cosmeceutical ingredient and on further studies should be performed to better understand the impact of S. nigra compounds on skin care over the time.

scholarly journals Biogenic Synthesis of Silver Nanoparticles with Antimicrobial Properties

2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Evangelia A Pavlatou
Keyword(s):  
Silver Nanoparticles ◽  
Antimicrobial Properties ◽  
Public Health Problem ◽  
Integrated Approach ◽  
Synthetic Methods ◽  
Synthesis Process ◽  
Major Public Health Problem ◽  
Biogenic Synthesis ◽  
Wide Range ◽  
Bacteria And Fungi

The transmission of a wide range of diseases, related to the infection by pathogenic microorganisms is a major public health problem that daily endangers the safety of human population. Silver has been thoroughly studied and used against bacteria due to its antimicrobial properties. Nanostructured silver gathers all the advantages of the silver itself, as well as the advanced performance of the nanomaterials. Thus, currently, silver nanoparticles constitute the most widely used kind of nanoparticles in biomedicine, due to their attractive antimicrobial properties. A variety of physical and chemical methods are employed for the AgNPs synthesis. However, many of them include the use of toxic reagents or require large amounts of energy, during the synthesis process. For this reason, many eco-friendly methods are proposed in order to synthesize AgNPs. Hence, biogenic synthesis of AgNPs, utilizing biological resources opens a novel route for the development of alternative production processes.These methods seem to have significant advantages, as the extracts contribute positively to the formation and enhancement of the antimicrobial activity of AgNPs, also acting as protective agents of the produced particles. In this review an integrated approach of AgNPs bio-synthetic methods using microorganisms, such as bacteria and fungi, plants and plant extracts, as well as several templates, like DNA and viruses is discussed, shedding light on the comparative advantages of them.

scholarly journals Evaluation of Binding of Rosmarinic Acid with Human Transferrin and Its Impact on the Protein Structure: Targeting Polyphenolic Acid-Induced Protection of Neurodegenerative Disorders

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Anas Shamsi ◽  
Saleha Anwar ◽  
Mohd Shahbaaz ◽  
Taj Mohammad ◽  
Mohamed F. Alajmi ◽  
...  
Keyword(s):  
Neurodegenerative Disorders ◽  
Rosmarinic Acid ◽  
Natural Compound ◽  
Iron Homeostasis ◽  
Biological Activities ◽  
Pivotal Role ◽  
Titration Calorimetry ◽  
Static Mode ◽  
Human Transferrin ◽  
Wide Range

Rosmarinic acid (RA) is a natural compound that is gaining wide popularity owing to its broad-spectrum biological activities. RA is known for its wide range of medicinal properties and therapeutic applications in a vast range of neurodegenerative disorders thus making it a vital natural compound. Human transferrin (hTf) is a clinically significant protein that plays a pivotal role in maintaining iron homeostasis. The importance of studies pertaining to hTf is attributable to the pivotal role of iron deposition in CNS in neurodegenerative disorders. The study was intended to have an insight into the interaction between RA and hTf employing multispectroscopic approach, molecular docking, and molecular dynamic simulation studies. Fluorescence quenching studies revealed that RA shows an excellent binding affinity to hTf with a binding constant ( K ) of 107 M-1 and is guided by static mode of quenching. Isothermal titration calorimetry (ITC) further validated the spontaneous nature of binding. The estimation of enthalpy change (∆H) and entropy change (∆S) suggested that the RA-hTf complex formation is driven by hydrogen bonding, thereby making this process seemingly specific. Further, Fourier transform infrared (FTIR) and circular dichroism (CD) spectra suggested that RA induces conformational and structural changes in hTf. Additionally, molecular dynamics (MD) studies were carried out to investigate the stability of the hTf and hTf–RA system and suggested that binding of RA induces structural alteration in hTf with free hTf being more stable. This study provides a rationale to use RA in drug development against neurodegenerative disorders by designing novel functional foods containing RA.

scholarly journals Therapeutic Potential of Cucumis Melo (L). Fruit Extract and Its Silver Nanopartciles Against Den Induced Hepatocellular Cancer in Rats

2021 ◽  
Author(s):  
R Vidya ◽  
K Kalaivani ◽  
P Amudha
Keyword(s):  
Silver Nanoparticles ◽  
Protective Effect ◽  
Cucumis Melo ◽  
Biological Activities ◽  
Hematological Parameters ◽  
Research Work ◽  
Histological Evaluation ◽  
Fruit Extract ◽  
Standard Drug ◽  
Wide Range

Abstract Biosynthesized silver nanoparticles have a wide range of biological activities and using nanoparticles as one of the novel approaches in cancer therapy. In this present research work, the anticancer efficacy of Cucumis melo fruit extract and its silver nanoparticles was explored. Wistar rats were divided into six groups and hepatic cancer was induced with 0.01 % DEN (diethylnitrosamine) through drinking water for 16 weeks. Cyclophosphamide was given as the standard drug at the dose of 50 mg / kg body weight. Hematological Parameters showed a decrease in the levels of hemoglobin (Hb), packed cell volume (PCV), red blood cells (RBC), mean corpuscular volume (MCV), mean corpuscular Hb (MCH), mean corpuscular Hb concentration (MCHC), and platelets (PLTS) levels except white blood cell (WBC) in DEN induced cancer animals. Significant alterations in the hematological parameters were observed after treatment which indicate the protective effect of Cucumis melo fruit on the hemopoietic system. The levels of liver function markers such as transaminases (AST ALT, ALP, LDH, GGT and 5’NT were significantly elevated in serum and liver of cancer bearing rats. Treatment with crude extract and silver nanoparticles of Cucumis melo fruit, indicating that Cucumis melo fruit could have exerted its protective effect. The levels of serum tumor markers viz., Alpha feto protein (AFP) and Carcinoembryonic antigen (CEA) elevated in rats induced with DEN, which then were reduced following Cucumis melo fruit treatment, indicating the anticancer activity of the drug. Histological evaluation of liver and kidney were also performed to authenticate the present work.

scholarly journals Modulatory Role of Silver Nanoparticles and Mesenchymal Stem Cell–Derived Exosome-Modified Barrier Membrane on Macrophages and Osteogenesis

2021 ◽  
Vol 9 ◽  
Author(s):  
Haiping Lu ◽  
Yi Zhang ◽  
Shan Xiong ◽  
Yinghong Zhou ◽  
Lan Xiao ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Surface Modification ◽  
Ag Nanoparticles ◽  
Biological Activities ◽  
Membrane Surface ◽  
Microscopy Study ◽  
Barrier Membrane ◽  
Modification Technique ◽  
The Impact ◽  
Hybrid Scaffolds

Background: As a wound dressing and barrier membrane, surface modification of polycaprolactone (PCL) is needed in order to achieve better biological activities. Exosomes derived from mesenchymal stem cells (MSCs) hold significant tissue regeneration promise. Silver nanoparticles (Ag) have been suggested as the surface modification technique for various medical devices.Materials and Methods: Ag and human bone marrow MSC (hBMSC)-derived exosomes (MSCs-exo) were used to modify the PCL scaffold. The impact of different scaffolds on immune cells and MSC proliferation and differentiation was further evaluated.Results: MSCs-exo exhibited cup-shaped morphology with a diameter around 100 nm. MSCs-exo were enriched with exosome marker CD81 and showed good internalization into recipient cells. 200 ng/ml Ag nanoparticles and MSCs-exo were further used to modify the PCL scaffold. The internalization study further indicated a similar releasing pattern of exosomes from Ag/MSCs-exo hybrid scaffolds into RAW264.7 and hBMSCs at 12 and 24 h, respectively. Macrophages play an important role during different stages of bone regeneration. The MTT and confocal microscopy study demonstrated no significant toxicity of exosome and/or Ag hybrid scaffolds for macrophages and MSCs. Inflammatory macrophages were further used to mimic the inflammatory environment. A mixed population of elongated and round morphology was noted in the exosome and Ag hybrid group, in which the proinflammatory genes and secretion of IL-6 and TNF-α were significantly reduced. In addition, the exosome and Ag hybrid scaffolds could significantly boost the osteogenic differentiation of hBMSCs.Discussion: This study highlights the possibility of using Ag nanoparticles and MSCs-exo to modify the PCL scaffold, thus providing new insight into the development of the novel immunomodulatory biomembrane.

scholarly journals Multi-Omics Analysis of Oral Bacterial Biofilm on Titanium Oxide Nanostructure Modified Implant Surface: in Vivo Sequencing-Based Pilot Study in Beagle Dogs

2021 ◽  
Author(s):  
Hanyu Sun ◽  
Yuki Chan ◽  
Xuan Li ◽  
Ruogu Xu ◽  
Zhengchuan Zhang ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Antimicrobial Properties ◽  
Surface Modifications ◽  
Titanium Implants ◽  
Bacterial Biofilm ◽  
Bacterial Invasion ◽  
Oral Microbiota ◽  
Minimal Impact ◽  
The Impact

Abstract Background and aimsSurface modifications of titanium implants play essential role in facilitating osteointegration and enhancing their antimicrobial properties, while the latter is critical for preventing infectious diseases caused by the biofilm. However, it remains unknown about how the surface modifications could affect the composition and functional gene expression of oral microbiota deposited on the titanium implants. In this study, we aimed to investigate the impact of different nanostructured surfaces on the biofilm in vivo.ResultsNanophase calcium phosphate were successfully deposited into or between the TiO2 nanotubes with a diameter of 70–90 nm. NT and NTN surfaces showed increased roughness than the MP surface. XPS spectra showed that the O 1s was mainly divided into two bands in MP and NT samples, including Ti-O and -OH, while the surface modification of TiO2 nanotube in NT accounted for the increased intensity of Ti-O with the reference to that in MP samples. After the deposition of calcium phosphate, two new elemental peaks of Ca and P can be identified from the XPS survey spectrum of NTN. Moreover, the O 1s of NTN sample could be differentiated into three peaks, while the new one represented the -PO band. The 16S rDNA sequencing results showed that NT and NTN had minimal impact on the diversity and community structure of oral microbiota. Metatranscriptomic sequencing revealed that differentially expressed genes (DEGs) mostly differed in the terms of the biological process and cellular component on different surfaces. Gene Ontology (GO) terms enrichment indicated that NTN down-regulate the genes associated in localization and locomotion. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that the DEGs were associated with microbial metabolism, protein synthesis and bacterial invasion of epithelial cells.ConclusionTiO2 nanotube and calcium phosphate-coated TiO2 nanotube despite improving the antimicrobial properties of implant surfaces, had unexpectedly minimal impact on the microbiome composition and diversity. Notably, nanostructured titanium surfaces could inhibit the bacterial migration and colonization, down-regulate the pathogen invasion pathways, and further destruct bacterial cellular membrane, all in all, conferred the bactericidal properties.

scholarly journals In Vitro and In Silico Evaluation of Biological Activity of a New Series of Oxadiazole Compounds Against Esp Gene Expression in Enterococcus faecalis Biofilm

2021 ◽  
Vol In Press (In Press) ◽  
Author(s):  
Sepideh Ghameshlouei ◽  
Nakisa Zarrabi Ahrabi ◽  
Yasin SarveAhrabi
Keyword(s):  
Enterococcus Faecalis ◽  
Biofilm Formation ◽  
Biological Activities ◽  
Control Sample ◽  
Surface Protein ◽  
Bacterial Biofilm ◽  
Receptor Binding Site ◽  
Wide Range ◽  
Oxadiazole Derivatives ◽  
The Impact

Background: The enterococcal surface protein (Esp) is a high-molecular-weight surface protein of biofilm creating agent in Enterococcus faecalis. Oxadiazoles have a wide range of biological activities. Objective: This research aimed to examine the impact of new oxadiazole derivatives on the expression of Esp, playing an important role in promoting the biofilm formation ability of drug-resistant E. faecalis strains. Method: 1, 3, 4-oxadiazole derivatives were synthesized through a one-step synthesis. E. faecalis strains were collected and isolated from hospitals in Tehran. The antimicrobial properties of the synthesized materials against the isolated strains were investigated. RNA, DNA, and cDNA were extracted, and the relative expression of Esp in E. faecalis isolates was evaluated by real-time PCR. Docking study was performed by AutoDock vina software, and the resulting docking poses were analyzed using Discovery Studio 4.5 Client software. Results: The use of synthesized derivatives changed the Esp expression level in different isolates compared to the control sample. The two compounds containing naphthalene (4f) and methoxyphenyl (4g) caused respectively a 2-fold and a 3-fold decrease in Esp expression compared to the control sample. The compound 4f with the best binding energy among the compounds (-9.2) had the most hydrogen and hydrophobic bonds with the receptor-binding site. Conclusions: 1, 3, 4-oxadiazole derivatives, especially naphthalene and methoxyphenyl, act as inhibitors of bacterial biofilm formation and can be used in the pharmaceutical and biological industries.

scholarly journals Novel Azoles as Antiparasitic Remedies against Brain-Eating Amoebae

Antibiotics ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 188 ◽  
Author(s):  
Ayaz Anwar ◽  
Mohammad Ridwane Mungroo ◽  
Simal Khan ◽  
Itrat Fatima ◽  
Rafaila Rafique ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Silver Nanoparticles ◽  
Nervous System ◽  
Heterocyclic Compounds ◽  
Antimicrobial Properties ◽  
Static Properties ◽  
Cytotoxicity Assays ◽  
Wide Range ◽  
The Central Nervous System ◽  
Tetrazole Derivatives

Balamuthia mandrillaris and Naegleria fowleri are opportunistic protozoan pathogens capable of producing infection of the central nervous system with more than 95% mortality rate. Previously, we have synthesized several compounds with antiamoebic properties; however, synthesis of compounds that are analogues of clinically used drugs is a highly desirable approach that can lead to effective drug development against these devastating infections. In this regard, compounds belonging to the azole class possess wide range of antimicrobial properties and used clinically. In this study, six novel benzimidazole, indazole, and tetrazole derivatives were synthesized and tested against brain-eating amoebae. These compounds were tested for their amoebicidal and static properties against N. fowleri and B. mandrillaris. Furthermore, the compounds were conjugated with silver nanoparticles and characterized. The synthetic heterocyclic compounds showed up to 72% and 65% amoebicidal activities against N. fowleri and B. mandrillaris respectively, while expressing up to 75% and 70% amoebistatic activities, respectively. Following conjugation with silver nanoparticles, amoebicidal activities of the drugs increased by up to 46 and 36% versus B. mandrillaris and N. fowleri. Minimal effects were observed when the compounds were evaluated against human cells using cytotoxicity assays. In summary, azole compounds exhibited potent activity against N. fowleri and B. mandrillaris. Moreover, conjugation of the azole compounds with silver nanoparticles further augmented the capabilities of the compounds against amoebae.

scholarly journals Antiadherence and Antimicrobial Properties of Silver Nanoparticles against Streptococcus mutans on Brackets and Wires Used for Orthodontic Treatments

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
León Francisco Espinosa-Cristóbal ◽  
Natalie López-Ruiz ◽  
Denisse Cabada-Tarín ◽  
Simón Yobanny Reyes-López ◽  
Armando Zaragoza-Contreras ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Antimicrobial Properties ◽  
Dental Enamel ◽  
Inhibitory Effect ◽  
White Spot Lesions ◽  
Inhibitory Effects ◽  
Atomic Force ◽  
Topographic Characteristics ◽  
Microbiological Assays ◽  
Potential Use

White spot lesions (WSLs) are very frequent alterations during orthodontic treatments causing demineralization of the dental enamel. Various dental treatments have been developed to prevent WSLs; the prevalence and incidence of these lesions remain significantly high. Although silver nanoparticles (AgNPs) have demonstrated good inhibitory effects against several microorganisms, more studies about antiadherence activity on different orthodontic appliance surfaces are necessary. To determine the inhibitory effect and antiadherence activity of AgNPs on the adhesion of S. mutans on surfaces of brackets and wires for orthodontic therapies, two sizes of AgNPs were prepared and characterized. The evaluation of S. mutans adhesion was performed with microbiological assays on surfaces of brackets and orthodontic modules in triplicate. Topographic characteristics of orthodontic brackets and wires were made by scanning electron and atomic force microscopies. All AgNP samples inhibited S. mutans adhesion; however, the smaller AgNPs had better inhibition than the larger ones. The presence of the module influenced the adhesion of S. mutans but not in the activity of AgNPs. The AgNPs used in this study showed to have good antimicrobial and antiadherence properties against S. mutans bacteria determining its high potential use for the control of WSLs in orthodontic treatments.

Sign in / Sign up

Export Citation Format

Share Document