Effect of Gold Nanoparticles and Silicon on the Bioactivity and Antibacterial Properties of Hydroxyapatite/Chitosan/Tricalcium Phosphate-Based Biomicroconcretes

Bioactive, chemically bonded bone substitutes with antibacterial properties are highly recommended for medical applications. In this study, biomicroconcretes, composed of silicon modified (Si-αTCP) or non-modified α-tricalcium phosphate (αTCP), as well as hybrid hydroxyapatite/chitosan granules non-modified and modified with gold nanoparticles (AuNPs), were designed. The developed biomicroconcretes were supposed to combine the dual functions of antibacterial activity and bone defect repair. The chemical and phase composition, microstructure, setting times, mechanical strength, and in vitro bioactive potential of the composites were examined. Furthermore, on the basis of the American Association of Textile Chemists and Colorists test (AATCC 100), adapted for chemically bonded materials, the antibacterial activity of the biomicroconcretes against S. epidermidis, E. coli, and S. aureus was evaluated. All biomicroconcretes were surgically handy and revealed good adhesion between the hybrid granules and calcium phosphate-based matrix. Furthermore, they possessed acceptable setting times and mechanical properties. It has been stated that materials containing AuNPs set faster and possess a slightly higher compressive strength (3.4 ± 0.7 MPa). The modification of αTCP with silicon led to a favorable decrease of the final setting time to 10 min. Furthermore, it has been shown that materials modified with AuNPs and silicon possessed an enhanced bioactivity. The antibacterial properties of all of the developed biomicroconcretes against the tested bacterial strains due to the presence of both chitosan and Au were confirmed. The material modified simultaneously with AuNPs and silicon seems to be the most promising candidate for further biological studies.

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Plasmon-Enhanced Antibacterial Activity of Chiral Gold Nanoparticles and In Vivo Therapeutic Effect

Nanomaterials ◽

10.3390/nano11061621 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1621

Author(s):

Yuelong Xu ◽

Hongxia Wang ◽

Min Zhang ◽

Jianhao Zhang ◽

Wenjing Yan

Keyword(s):

Gold Nanoparticles ◽

Antibacterial Activity ◽

Intestinal Microflora ◽

Antibacterial Properties ◽

Au Nps ◽

E Coli ◽

Bacterial Cell Death ◽

Steric Configuration

d-cysteine (d-cys) has been demonstrated to possess an extraordinary antibacterial activity because of its unique steric configuration. However, inefficient antibacterial properties seriously hinder its wide applications. Here, cysteine-functionalized gold nanoparticles (d-/l-Au NPs) were prepared by loading d-/l-cysteine on the surface of gold nanoparticles for the effective inhibition of Escherichia coli (E. coli) in vitro and in vivo, and the effects on the intestinal microflora in mice were explored during the treatment of E. coli infection in the gut. We found that the antibacterial activity of d-/l-Au NPs was more than 2–3 times higher than pure d-cysteine, l-cysteine and Au NPs. Compared with l-Au NPs, d-Au NPs showed the stronger antibacterial activity, which was related to its unique steric configuration. Chiral Au NPs showed stronger destructive effects on cell membrane compared to other groups, which further leads to the leakage of the cytoplasm and bacterial cell death. The in vivo antibacterial experiment illustrated that d-Au NPs displayed impressive antibacterial activity in the treatment of E. coli-infected mice comparable to kanamycin, whereas they could not affect the balance of intestinal microflora. This work is of great significance in the development of an effective chiral antibacterial agent.

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Synthesis, Molecular Modelling and Antibacterial Activity Against Helicobacter pylori of Novel Diflunisal Derivatives as Urease Enzyme Inhibitors

Letters in Drug Design & Discovery ◽

10.2174/1570180815666180627130208 ◽

2019 ◽

Vol 16 (4) ◽

pp. 392-400 ◽

Cited By ~ 2

Author(s):

Göknil Pelin Coşkun ◽

Teodora Djikic ◽

Sadık Kalaycı ◽

Kemal Yelekçi ◽

Fikrettin Şahin ◽

...

Keyword(s):

Helicobacter Pylori ◽

Antibacterial Activity ◽

Enzyme Inhibitors ◽

Binding Modes ◽

Bacterial Strains ◽

Urease Enzyme ◽

H Pylori ◽

Ulcer Treatment ◽

Main Factor

Background:The main factor for the prolongation of the ulcer treatment in the gastrointestinal system would be Helicobacter pylori infection, which can possibly lead to gastrointestinal cancer. Triple therapy is the treatment of choice by today's standards. However, observed resistance among the bacterial strains can make the situation even worse. Therefore, there is a need to discover new targeted antibacterial therapy in order to make success in the eradication of H. pylori infections.Methods:The targeted therapy rule is to identify the related macromolecules that are responsible for the survival of the bacteria. Thus, 2-[(2',4'-difluoro-4-hydroxybiphenyl-3-yl)carbonyl]-N- (substituted)hydrazinocarbothioamide (3-13) and 5-(2',4'-difluoro-4-hydroxybiphenyl-3-yl)-4- (substituted)-2,4-dihydro-3H-1,2,4-triazole-3-thiones (14-17) were synthesized and evaluated for antibacterial activity in vitro against H. pylori.Results:All of the tested compounds showed remarkable antibacterial activity compared to the standard drugs (Ornidazole, Metronidazole, Nitrimidazin and Clarithromycin). Compounds 4 and 13 showed activity as 2µg/ml MIC value.Conclusion:In addition, we have investigated binding modes and energy of the compounds 4 and 13 on urease enzyme active by using the molecular docking tools.

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In Vitro Anti-Biofilm and Antibacterial Properties of Streptococcus downii sp. nov.

Microorganisms ◽

10.3390/microorganisms9020450 ◽

2021 ◽

Vol 9 (2) ◽

pp. 450

Author(s):

Maigualida Cuenca ◽

María Carmen Sánchez ◽

Pedro Diz ◽

Lucía Martínez-Lamas ◽

Maximiliano Álvarez ◽

...

Keyword(s):

Antibacterial Activity ◽

Quantitative Polymerase Chain Reaction ◽

Bacterial Load ◽

Antibacterial Properties ◽

Antibacterial Activities ◽

Oral Bacteria ◽

Periodontal Pathogens ◽

Biofilm Model ◽

Biofilm Development

The aim of this study was to evaluate the potential anti-biofilm and antibacterial activities of Streptococcus downii sp. nov. To test anti-biofilm properties, Streptococcus mutans, Actinomyces naeslundii, Veillonella parvula, Fusobacterium nucleatum, Porphyromonas gingivalis, and Aggregatibacter actinomycetemcomitans were grown in a biofilm model in the presence or not of S. downii sp. nov. for up to 120 h. For the potential antibacterial activity, 24 h-biofilms were exposed to S. downii sp. nov for 24 and 48 h. Biofilms structures and bacterial viability were studied by microscopy, and the effect in bacterial load by quantitative polymerase chain reaction. A generalized linear model was constructed, and results were considered as statistically significant at p < 0.05. The presence of S. downii sp. nov. during biofilm development did not affect the structure of the community, but an anti-biofilm effect against S. mutans was observed (p < 0.001, after 96 and 120 h). For antibacterial activity, after 24 h of exposure to S. downii sp. nov., counts of S. mutans (p = 0.019) and A. actinomycetemcomitans (p = 0.020) were significantly reduced in well-structured biofilms. Although moderate, anti-biofilm and antibacterial activities of S. downii sp. nov. against oral bacteria, including some periodontal pathogens, were demonstrated in an in vitro biofilm model.

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Preparation of bioactive and antibacterial PMMA-based bone cement by modification with quaternary ammonium and alkoxysilane

Journal of Biomaterials Applications ◽

10.1177/08853282211004413 ◽

2021 ◽

pp. 088532822110044

Author(s):

Haiyang Wang ◽

Toshinari Maeda ◽

Toshiki Miyazaki

Keyword(s):

Antibacterial Activity ◽

Methyl Methacrylate ◽

Bone Cement ◽

Setting Time ◽

Antibacterial Properties ◽

The Body ◽

Apatite Formation ◽

Gram Positive ◽

E Coli ◽

Gram Positive Bacteria

Bone cement based on poly(methyl methacrylate) (PMMA) powder and methyl methacrylate (MMA) liquid is a very popular biomaterial used for the fixation of artificial joints. However, there is a risk of this cement loosening from bone because of a lack of bone-bonding bioactivity. Apatite formation in the body environment is a prerequisite for cement bioactivity. Additionally, suppression of infection during implantation is required for bone cements to be successfully introduced into the human body. In this study, we modified PMMA cement with γ-methacryloxypropyltrimetoxysilane and calcium acetate to introduce bioactive properties and 2-( tert-butylamino)ethyl methacrylate (TBAEMA) to provide antibacterial properties. The long-term antibacterial activity is attributed to the copolymerization of TBAEMA and MMA. As the TBAEMA content increased, the setting time increased and the compressive strength decreased. After soaking in simulated body fluid, an apatite layer was detected within 7 days, irrespective of the TBAEMA content. The cement showed better antibacterial activity against Gram-negative E. Coli than Gram-positive bacteria; however, of the Gram-positive bacteria investigated, B. subtilis was more susceptible than S. aureus.

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Synthesis, Characterization, Antibacterial Properties, and In Vitro Studies of Selenium and Strontium Co-Substituted Hydroxyapatite

International Journal of Molecular Sciences ◽

10.3390/ijms22084246 ◽

2021 ◽

Vol 22 (8) ◽

pp. 4246

Author(s):

Muhammad Maqbool ◽

Qaisar Nawaz ◽

Muhammad Atiq Ur Atiq Ur Rehman ◽

Mark Cresswell ◽

Phil Jackson ◽

...

Keyword(s):

Negative Impact ◽

Antibacterial Properties ◽

Biological Properties ◽

Ion Concentration ◽

Charge Composition ◽

Bacterial Strains ◽

X Ray Diffraction ◽

Molar Ratios ◽

Human Osteosarcoma Cells

In this study, as a measure to enhance the antimicrobial activity of biomaterials, the selenium ions have been substituted into hydroxyapatite (HA) at different concentration levels. To balance the potential cytotoxic effects of selenite ions (SeO32−) in HA, strontium (Sr2+) was co-substituted at the same concentration. Selenium and strontium-substituted hydroxyapatites (Se-Sr-HA) at equal molar ratios of x Se/(Se + P) and x Sr/(Sr + Ca) at (x = 0, 0.01, 0.03, 0.05, 0.1, and 0.2) were synthesized via the wet precipitation route and sintered at 900 °C. The effect of the two-ion concentration on morphology, surface charge, composition, antibacterial ability, and cell viability were studied. X-ray diffraction verified the phase purity and confirmed the substitution of selenium and strontium ions. Acellular in vitro bioactivity tests revealed that Se-Sr-HA was highly bioactive compared to pure HA. Se-Sr-HA samples showed excellent antibacterial activity against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus carnosus) bacterial strains. In vitro cell–material interaction, using human osteosarcoma cells MG-63 studied by WST-8 assay, showed that Se-HA has a cytotoxic effect; however, the co-substitution of strontium in Se-HA offsets the negative impact of selenium and enhanced the biological properties of HA. Hence, the prepared samples are a suitable choice for antibacterial coatings and bone filler applications.

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A New Supported Manganese-Based Coordination Complex as a Nano-Catalyst for the Synthesis of Indazolophthalazinetriones and Investigation of Its Antibacterial Activity

Chemistry ◽

10.3390/chemistry3030056 ◽

2021 ◽

Vol 3 (3) ◽

pp. 783-799

Author(s):

Maryam Ariannezhad ◽

Davood Habibi ◽

Somayyeh Heydari ◽

Vahideh Khorramabadi

Keyword(s):

Antibacterial Activity ◽

Simple Procedure ◽

Condensation Reaction ◽

Antibacterial Properties ◽

Coordination Complex ◽

Bacterial Strains ◽

One Pot ◽

Nano Catalyst ◽

Ft Ir ◽

The One

A new magnetic supported manganese-based coordination complex (Fe3O4@SiO2@CPTMS@MBOL@ Mn) was prepared in consecutive stages and characterized via various techniques (VSM, SEM, TEM, XRD, FT-IR, EDX, TG-DTA, and ICP). To evaluate its application, it was used for synthesis of divers Indazolophthalazinetriones in a simple procedure via the one-pot three-component condensation reaction of aldehydes, dimedone, and phthalhydrazide in ethanol under reflux conditions. The Mn catalyst can be recycled without any noticeable loss in catalytic activity. Additionally, the antibacterial properties of the nano-catalyst were studied against some bacterial strains.

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Synthesis and Characterization of a Bioartificial Polymeric System with Potential Antibacterial Activity: Chitosan-Polyvinyl Alcohol-Ampicillin

Molecules ◽

10.3390/molecules23123109 ◽

2018 ◽

Vol 23 (12) ◽

pp. 3109 ◽

Cited By ~ 3

Author(s):

Andres Bernal-Ballen ◽

Jorge Lopez-Garcia ◽

Martha-Andrea Merchan-Merchan ◽

Marian Lehocky

Keyword(s):

Antibacterial Activity ◽

Polyvinyl Alcohol ◽

Statistical Significance ◽

Antibacterial Properties ◽

Intermolecular Forces ◽

Polymeric System ◽

Bacterial Strains ◽

Natural Polymers ◽

The Matrix ◽

The Individual

Bio-artificial polymeric systems are a new class of polymeric constituents based on blends of synthetic and natural polymers, designed with the purpose of producing new materials that exhibit enhanced properties with respect to the individual components. In this frame, a combination of polyvinyl alcohol (PVA) and chitosan, blended with a widely used antibiotic, sodium ampicillin, has been developed showing a moderate behavior in terms of antibacterial properties. Thus, aqueous solutions of PVA at 1 wt.% were mixed with acid solutions of chitosan at 1 wt.%, followed by adding ampicillin ranging from 0.3 to 1.0 wt.% related to the total amount of the polymers. The prepared bio-artificial polymeric system was characterized by FTIR, SEM, DSC, contact angle measurements, antibacterial activity against Staphylococcus aureus and Escherichia coli and antibiotic release studies. The statistical significance of the antibacterial activity was determined using a multifactorial analysis of variance with ρ < 0.05 (ANOVA). The characterization techniques did not show alterations in the ampicillin structure and the interactions with polymers were limited to intermolecular forces. Therefore, the antibiotic was efficiently released from the matrix and its antibacterial activity was preserved. The system disclosed moderate antibacterial activity against bacterial strains without adding a high antibiotic concentration. The findings of this study suggest that the system may be effective against healthcare-associated infections, a promising view in the design of novel antimicrobial biomaterials potentially suitable for tissue engineering applications.

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Antibacterial Activity of Leukocyte- and Platelet-Rich Plasma: AnIn VitroStudy

BioMed Research International ◽

10.1155/2018/9471723 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 7

Author(s):

Agata Cieślik-Bielecka ◽

Tadeusz Bold ◽

Grzegorz Ziółkowski ◽

Marcin Pierchała ◽

Aleksandra Królikowska ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Enterococcus Faecalis ◽

Platelet Rich Plasma ◽

Antibacterial Properties ◽

Antimicrobial Effect ◽

Diffusion Method ◽

Bacterial Strains ◽

Bovine Thrombin ◽

Zones Of Inhibition

The aim of the study was to investigate the leukocyte- and platelet-rich plasma (L-PRP) antimicrobial activity. The studied sample comprised 20 healthy males. The L-PRP gel, liquid L-PRP, and thrombin samples were testedin vitrofor their antibacterial properties against selected bacterial strains using the Kirby-Bauer disc diffusion method. Two types of thrombin were used (autologous and bovine). Zones of inhibition produced by L-PRP ranged between 6 and 18 mm in diameter. L-PRP inhibited the growth ofStaphylococcus aureus(MRSA and MSSA strains) and was also active againstEnterococcus faecalisandPseudomonas aeruginosa. There was no activity againstEscherichia coliandKlebsiella pneumoniae. The statistically significant increase of L-PRP antimicrobial effect was noted with the use of major volume of thrombin as an activator. Additionally, in groups where a bovine thrombin mixture was added to L-PRP the zones of inhibition concerning MRSA,Enterococcus faecalis, andPseudomonas aeruginosawere larger than in the groups with autologous thrombin. Based on the conducted studies, it can be determined that L-PRP can evokein vitroantimicrobial effects and might be used to treat selected infections in the clinical field. The major volume of thrombin as an activator increases the strength of the L-PRP antimicrobial effect.

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