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1.
Small ; 20(26): e2309972, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38279615

RESUMO

In this work, novel ternary composite ZIF-67/Ag NPs/NaYF4:Yb,Er is synthesized by solvothermal method. The photocatalytic activity of the composite is evaluated by sulfadiazine (SDZ) degradation under simulated sunlight. High elimination efficiency of the composite is 95.4% in 180 min with good reusability and stability. The active species (h+, ·O2 - and ·OH) are identified. The attack sites and degradation process of SDZ are deeply investigated based on theoretical calculation and liquid chromatography-mass spectrometry analysis. The upconversion mechanism study shows that favorable photocatalytic effectiveness is attributed to the full utilization of sunlight through the energy transfer upconversion process and fluorescence resonance energy transfer. Additionally, the composite is endowed with outstanding light-absorbing qualities and effective photogenerated electron-hole pair separation thanks to the localized surface plasmon resonance effect of Ag nanoparticles. This work can motivate further design of novel photocatalysts with upconversion luminescence performance, which are applied to the removal of sulphonamide antibiotics in the environment.

2.
Environ Sci Technol ; 58(1): 895-905, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38134359

RESUMO

N2O is a common byproduct in the selective catalytic oxidation of ammonia, and its generation often needs to be inhibited due to its strong greenhouse effect. In this paper, using Ag/ZSO-Y as a model catalyst, the N2O selectivity was reduced by 30% through modulation of the electron metal-support interaction. The results demonstrate that the work function of the support can be regulated by the content of the doping element. As the Zr content increases in SnO2, the work function of the support decreases. Moreover, there is a positive correlation between the charge transfer amount and the work function of the support. A series of in situ DRIFTS and density functional theory calculations revealed that the -NO and -N reactions are the primary pathways for N2O formation. By adjustment of the work function of the support through varying the Zr doping level, the electronic structure of Ag NPs was further tuned, resulting in an increased reaction energy barrier for -NO and -N reactions, effectively suppressing N2O formation.


Assuntos
Amônia , Elétrons , Amônia/química , Amônia/metabolismo , Oxirredução , Metais , Catálise
3.
Lasers Med Sci ; 39(1): 43, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38246979

RESUMO

The evolution of parasite resistance to antiparasitic agents has become a serious health issue indicating a critical and pressing need to develop new therapeutics that can conquer drug resistance. Nanoparticles are novel, promising emerging drug carriers that have demonstrated efficiency in treating many parasitic diseases. Lately, attention has been drawn to a broad-spectrum nanoparticle capable of converting absorbed light into heat via the photothermal effect phenomenon. The present study is the first to assess the effect of silver nanoparticles (Ag NPs) and iron oxide nanoparticles (Fe3O4 NPs) as sole agents and with the combined action of the light-emitting diode (LED) on Blastocystis hominins (B. hominis) in vitro. Initially, the aqueous synthesized nanoparticles were characterized by UV-Vis spectroscopy, zeta potential, and transmission electron microscopy (TEM). The anti-blastocyst efficiency of these NPs was tested separately in dark conditions. As these NPs have a wide absorption spectrum in the visible regions, they were also excited by a continuous wave LED of wavelength band (400-700 nm) to test the photothermal effect. The sensitivity of B. hominis cysts was evaluated using scanning laser confocal microscopy whereas the live and dead cells were accurately segmented based on superpixels and the k-mean clustering algorithm. Our findings showed that this excitation led to hyperthermia that induced a significant reduction in the number of cysts treated with photothermally active NPs. The results of this study elucidate the potential role of photothermally active NPs as an effective anti-blastocystis agent. By using this approach, new therapeutic antiparasitic agents can be developed.


Assuntos
Blastocystis hominis , Cistos , Nanopartículas Metálicas , Humanos , Prata/farmacologia , Antiparasitários , Nanopartículas Magnéticas de Óxido de Ferro
4.
Odontology ; 112(2): 341-354, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37436660

RESUMO

Our study aimed to evaluate the antibacterial activities and dentin bond strengths of silver nanoparticles (Ag NPs) and silver nano-graphene oxide nanocomposites (Ag@nGO NCs) produced by green and chemical synthesis methods added to the dental adhesive. Ag NPs were produced by green synthesis (biogenic) (B-Ag NPs) and chemical synthesis methods (C-Ag NPs) and deposited on nGO (nano-graphene oxide). Ag NPs and Ag@nGO NCs (0.05% w/w) were added to the primer and bond (Clearfil SE Bond). Group 1: control, Group 2: nGO, Group 3: B-Ag NPs, Group 4: B-Ag@nGO NCs, Group 5: C-Ag NPs, Group 6: C-Ag@nGO NCs. Streptococcus mutans (S. mutans) live/dead assay analysis, MTT metabolic activity test, agar disc diffusion test, lactic acid production, and colony forming units (CFUs) tests were performed. Bond strength values were determined by the microtensile bond strength test (µTBS). Failure types were determined by evaluating with SEM. Statistical analysis was performed using one-way ANOVA and two-way ANOVA (p < 0.05). There was a difference between the groups in the viable bacteria ratio and lactic acid production tests (p < 0.05). When the inhibition zone and S. mutans CFUs were evaluated, there was no difference between Group 3 and Group 4 (p > 0.05), but there was a difference between the other groups (p < 0.05). When the metabolic activity of S. mutans was evaluated, there was a difference between Group 1 and other groups, and between Group 2 and Group 5, and Group 6 (p < 0.05). There was no difference between the groups in the µTBS values (p > 0.05). As a result, although the antibacterial activity of B-Ag NPs and B-Ag@nGO Ag NPs obtained by green synthesis is lower than that of chemically synthesis obtained C-Ag NPs and C-Ag@nGO NCs, they provided higher antibacterial activity compared to the control group and did not reduce µTBS. The addition of biogenic Ag NPs to the adhesive system increased the antibacterial effect by maintaining the bond strength of the adhesive. Antibacterial adhesives can increase the restoration life by protecting the tooth-adhesive interface.


Assuntos
Colagem Dentária , Nanopartículas Metálicas , Prata/farmacologia , Prata/química , Antibacterianos/farmacologia , Cimentos de Resina/química , Streptococcus mutans , Ácido Láctico/metabolismo , Ácido Láctico/farmacologia , Dentina , Resistência à Tração , Teste de Materiais , Cimentos Dentários/farmacologia , Cimentos Dentários/química , Adesivos Dentinários/química
5.
Int J Mol Sci ; 25(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38542055

RESUMO

The circular economy, which attempts to decrease agricultural waste while also improving sustainable development through the production of sustainable products from waste and by-products, is currently one of the main objectives of environmental research. Taking this view, this study used a green approach to synthesize two forms of silver nanoparticles: coated silver nanoparticles with olive leaf extract (Ag-olive) and uncoated pure silver nanoparticles (Ag-pure), which were produced by the calcination of Ag-olive at 550 °C. The extract and the fabricated nanoparticles were characterized by a variety of physicochemical techniques, including high-performance liquid chromatography (HPLC), thermal gravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Adult ticks (Hyalomma dromedarii) (Acari: Ixodidae) were used in this study to evaluate the antiparasitic activity of synthesized nanoparticles and extract. Furthermore, the antifungal activity was evaluated against Aspergillus aculeatus strain N (MW958085), Fuserium oxysporum (MT550034), and Alternaria tenuissiuma (MT550036). In both antiparasitic and antifungal tests, the as-synthesized Ag-olive showed higher inhibition activity than Ag-pure and olive leaf extract. The findings of this research suggest that Ag-olive may be a powerful and eco-friendly antiparasitic and antifungal agent. Ag-pure was also evaluated as a photocatalyst under sunlight for the detoxification of Eri-chrome-black T (EBT), methylene blue (MB), methyl orange (MO), and rhodamine B (RhB).


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Olea , Antifúngicos/farmacologia , Prata/química , Nanopartículas Metálicas/química , Antiparasitários , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Luz Solar , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
Int J Environ Health Res ; 34(2): 661-673, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36603148

RESUMO

The present research displays the green synthesis of stable silver nanoparticles (Ag-NPs) and copper oxide nanoparticles (CuO-NPs). The aqueous solution of Spirulina platensis (blue green algae) source was used as a reducing and capping agent and this study assessed the cytotoxicity of Ag- and CuO-NPs on three cancer cell cultures: A549 (lung cancer), HCT (human colon cancer), Hep2 (laryngeal carcinoma cancer) and normal cell (WISH). For NPs characterization, the UV/Vis spectroscopy was used where their formation and crystallinity were proven with λmax values for Ag- and CuO-NPs of 425 and 234 nm, respectively. According to X-ray diffraction and transmission electron microscopy (TEM), Ag-NPs were spherical in shape (size 2.23-14.68 nm) and CuO-NPs were small (size 3.75-12.4 nm). Zeta potential analysis showed the particles potential, which was recorded by -14.95 ± 4.31 mV for Ag-NPs and -21.63 ± 4.90 mV for CuO-NPs. After that, Ag- and CuO-NPs were assessed for anticancer properties against A549, HCT, Hep2 and WISH. IC50 of Ag-NPs recorded 15.67, 12.94, 3.8 and 10.44 µg/ml for WISH, A549, HCT and Hep2, respectively. IC50 for CuO-NPs was recorded as 32.64, 54.59, 3.98 and 20.56 µg/ml for WISH, A549, HCT and Hep2 cells, respectively. Safety limits for WISH and A549 were achieved 98.64% by 2.44 µg/ml and 83.43% by 4.88 µg/ml of Ag-NPs, and it was found to be 97.94% by 2.44 µg/ml against HCT, while that for Hep2 is 95.9% by 2.44 µg/ml. Concerning the anticancer effect of CuO-NPs, the safety limit was recorded as 88.70% by 2.44 and 98.48% by 4.88 µg/ml against WISH and A549, while HCT reached 89.92% by 2.44 µg/ml and Hep2 was 83.33% by 4.88 µg/ml. Green nanotechnology applications such as Ag-NPs and CuO-NPs have numerous benefits of ecofriendliness and compatibility for biomedical applications such as anticancer effects against cancer cells.


Assuntos
Nanopartículas Metálicas , Prata , Spirulina , Humanos , Prata/química , Prata/farmacologia , Cobre/química , Cobre/farmacologia , Microscopia Eletrônica de Transmissão
7.
Biochem Biophys Res Commun ; 688: 149126, 2023 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-37951153

RESUMO

The prospective contribution of phyto-nanotechnology to the synthesis of silver nanomaterials for biomedical purposes is attracting increasing interest across the world. Green synthesis of silver nanoparticles (Ag-NPs) through plants has been extensively examined recently, and it is now seen to be a green and efficient path for future exploitation and development of practical nano-factories. Fabrication of Ag-NPs is the process involves use of plant extracts/phyto-compounds (e.g.alkaloids, terpenoids, flavonoids, and phenolic compounds) to synthesise nanoparticles in more economical and feasible. Several findings concluded that in the field of medicine, Ag-NPs play a major role in pharmacotherapy (infection and cancer). Indeed, they exhibits novel properties but the reason is unclear (except some theoretical interpretation e.g. size, shape and morphology). But recent technological advancements help to address these questions by predicting the unique properties (composition and origin) by characterizing physical, chemical and biological properties. Due to increased list of publications and their application in the field of agriculture, industries and pharmaceuticals, issues relating to toxicity are unavoidable and question of debate. The present reviews aim to find out the role of plant extracts to synthesise Ag-NPs. It provides an overview of various phytocompounds and their role in the field of biomedicine (antibacterial, antioxidant, anticancer, anti-inflammatory etc.). In addition, this review also especially focused on various applications such as role in infection, oxidative stress, application in medical engineering, diagnosis and therapy, medical devices, orthopedics, wound healing and dressings. Additionally, the toxic effects of Ag-NPs in cell culture, tissue of different model organism, type of toxic reactions and regulation implemented to reduce associated risk are discussed critically. Addressing all above explanations, this review focus on the detailed properties of plant mediated Ag-NPs, its impact on biology, medicine and their commercial properties as well as toxicity.


Assuntos
Nanopartículas Metálicas , Prata , Prata/química , Nanopartículas Metálicas/química , Estudos Prospectivos , Extratos Vegetais/química , Antibacterianos/farmacologia
8.
Arch Microbiol ; 205(2): 72, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36693945

RESUMO

Microbial exopolysaccharides (EPS) are biocompatible, biodegradable, and less toxic substances secreted outside the cell. They adsorb metal cations to its surface, making it another captivating property, which helps in stabilizing and biosynthesizing metal nanoparticles. Owing to these properties, we adopted bacterial EPS toward the green synthesis of nanoparticles and its application in the removal of azo dyes. Extracted EPS weighed 2.6 mg/mL from the most potential isolate A07 with 385 µg/mg of the carbohydrate content. The top three isolates were subjected to nanoparticle synthesis via the intracellular method and, by their extracted EPS, silver nanoparticles (AgNP) with the size around 87 nm were successfully produced by both methods mediated by the most potent isolate. The nanoparticles were characterized by UV-Vis spectroscopy, X-ray diffraction studies, atomic force microscopy, and FT-IR analysis. The nanoparticles were employed for dye degradation of azo dyes, namely, Methyl Orange (MO) and Congo Red (CO). EPS-Ag NPs showed fair degradation capability determined by UV-Vis kinetic studies. The work suggests electron transfer from reducing agent to dye molecule mediated by nanoparticles, destroying the dye chromophore. This makes EPS-Ag NPs a suitable, cheap, and environment-friendly candidate for biodegradation of harmful azo dyes. The most potential isolate was identified as Bacillus stratosphericus by 16S rRNA sequencing and submitted to GenBank under the accession id MK968439.


Assuntos
Nanopartículas Metálicas , Nanopartículas Metálicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Cinética , RNA Ribossômico 16S , Prata/química , Compostos Azo/química
9.
Microb Cell Fact ; 22(1): 247, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053190

RESUMO

Photosynthetic cyanobacterial components are gaining great economic importance as prospective low-cost biostimulants for the green synthesis of metal nanoparticles with valuable medical and industrial applications. The current study comprises the biological synthesis of silver nanoparticles (Ag-NPs) using soluble polysaccharides isolated from Spirulina platensis (PSP) as reducing and capping agents. FTIR spectra showed major functional groups of PSP and biogenic silver nanoparticles including O-H, C-H (CH2), C-H (CH3), C=O, amide, and COO- groups. The UV/Vis spectroscopy scan analyses of the extracted PSP showed absorption spectra in the range of 200-400 nm, whereas the biogenic Ag-NPs showed a maximum spectrum at 285 nm. Transmission electron microscopy (TEM) analysis of the synthesized Ag-NPs showed spherical nanoparticles with mean size between 12 and 15.3 nm. The extracted PSP and Ag-NPs exhibited effective cytotoxic activity against Hep-G2 (human hepatocellular carcinoma). The IC50 for PSP and Ag-NPs were 65.4 and 24.5 µg/mL, respectively. Moreover, cell apoptosis assays for PSP and Ag-NPs against the growth of Hep-G2 cells revealed superior growth inhibitory effects of the green synthesized Ag-NPs that encouraged tracing the apoptotic signalling pathway. In conclusion, the current study demonstrated an unprecedented approach for the green synthesis of silver nanoparticles (NPs), using the polysaccharide of Spirulina platensis as reducing and capping agents, with superior anticancer activity against a hepatocellular carcinoma cell line.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanopartículas Metálicas , Humanos , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Carcinoma Hepatocelular/tratamento farmacológico , Estudos Prospectivos , Polissacarídeos , Extratos Vegetais/química , Extratos Vegetais/farmacologia
10.
Nanotechnology ; 35(9)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38029451

RESUMO

An electrical application of green synthesized silver nanoparticles (Ag NPs) by developing a unique bio-electrochemical cell (BEC) has been addressed in the report. Here, garlic extract (GE) has been used as a reducing agent to synthesize Ag NPs, and as a bio-electrolyte solution of BEC. Ag NPs successfully formed into face-centered cubic structures with average crystallite and particle sizes of 8.49 nm and 20.85 nm, respectively, according to characterization techniques such as the UV-vis spectrophotometer, XRD, FTIR, and FESEM. A broad absorption peak at 410 nm in the UV-visible spectra indicated that GE played a vital role as a reducing agent in the transformation of Ag+ions to Ag NPs. After that four types of BEC were developed by varying the concentration of GE, CuSO4. 5H2O, and Ag NPs electrolyte solution. The open circuit voltage and short circuit current of all cells were examined with the time duration. Moreover, different external loads (1 Ω, 2 Ω, 5 Ω, and 6 Ω) were used to investigate the load voltage and load current of BEC. The results demonstrated that the use of Ag NPs on BEC played a significant role in increasing the electrical performance of BEC. The use of GE-mediated Ag NPs integrated the power, capacity, voltage efficiency, and energy efficiency of BEC by decreasing the internal resistance and voltage regulation. These noteworthy results can take a frontier forward to the development of nanotechnology for renewable and low-cost power production applications.


Assuntos
Alho , Nanopartículas Metálicas , Prata/química , Alho/metabolismo , Nanopartículas Metálicas/química , Substâncias Redutoras , Antioxidantes/química , Eletrólitos , Extratos Vegetais/química
11.
Environ Res ; 231(Pt 1): 116045, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37146935

RESUMO

The alarming impact of antibiotic resistance sparked the quest for complementary treatments to overcome the confrontation over resistant pathogens. Metallic nanoparticles, especially silver nanoparticles (Ag NPs) have gained a much attention because of their remarkable biological characteristics. Moreover, their medicinal properties can be enhanced by preparing the composites with other materials. This article delves a comprehensive review of biosynthesis route for Ag NPs and their nanocomposites (NCs) with in-depth mechanism, methods and favorable experimental parameters. Comprehensive biological features Ag NPs such as antibacterial, antiviral, antifungal have been examined, with a focus on their potential uses in biomedicine and diagnostics has also been discussed. Additionally, we have also explored the hitches and potential outcomes of biosynthesis of Ag NPs in biomedical filed.


Assuntos
Nanopartículas Metálicas , Nanocompostos , Prata , Antibacterianos , Antivirais
12.
Environ Res ; 223: 115484, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36775091

RESUMO

The presence of chloride ion as an environmental pollutant is having a devastating and irreversible effect on aquatic and terrestrial ecosystems. To ensure safe and clean drinking water, it is vital to remove this substance using non-toxic and eco-friendly methods. This study presents a novel and highly efficient Ag NPs-modified bentonite adsorbent for removing chloride ion, a common environmental pollutant, from drinking water using a facile approach. The surface chemical properties and morphology of the pristine Na-bentonite and Ag NPs-Modified bentonite were characterized by field emission scanning electron microscopy (FESEM) and X-ray spectroscopy (EDX), X-Ray diffraction (XRD), Fourier transform infrared (FTIR), and zeta potential (ζ). To achieve maximum chloride ion removal, the effects of experimental parameters, including adsorbent dosage (1-9 g/L), chloride ion concentration (100-900 mg/L), and reaction time (5-25 h), were examined using the Response Surface Methodology (RSM). The chloride ion removal of 90% was obtained at optimum conditions (adsorbent dosage: 7 g/L, chloride ion concentration: 500 mg/L, and reaction time: 20 h). The adsorption isotherm and kinetics results indicated that the Langmuir isotherm model and pseudo-second-order kinetics were found suitable to chloride ion removal. Additionally, the regeneration and reusability of the Ag NPs-modified bentonite were further studied. In the regeneration and reusability study, the Ag NPs-modified bentonite has shown consistently ≥90% and ≥87% chloride ion removal even up to 2 repeated cycles, separately. Thus, the findings in this study provided convincing evidence for using Ag-NPs modified bentonite as a high-efficiency and promising adsorbent to remove chloride ion from drinking water.


Assuntos
Água Potável , Poluentes Químicos da Água , Bentonita/química , Cloretos , Ecossistema , Termodinâmica , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Adsorção , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Synth Met ; 293: 117235, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36567724

RESUMO

During the novel coronavirus pandemic, hydrogen peroxide (H2O2) played an important role as a disinfectant. However, high concentrations of H2O2 can also cause damage to the skin and eyes. Therefore, the quantitative and qualitative detection of H2O2 is an important research direction. In this work, we report a one-step laser-induced synthesis of graphene doped with Ag NPs composites. It directly trims screen printed electrodes (SPE). Firstly, we did the timekeeping current method (CA) test on H2O2 using a conventional platinum sheet as the counter electrode, and obtained linear ranges of 1-110 µM and 110-800 µM with a sensitivity of 118.7 and 96.3 µAmM-1cm-2 and a low detection limit of (LOD) 0.24 µM and 0.31 µM. On this basis we have also achieved a good result in CA testing using Screen printed carbon electrodes (SPCE), laying the foundation for portable testing. The sensor has excellent interference immunity and high selectivity.

14.
Mikrochim Acta ; 190(3): 100, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36821003

RESUMO

A ratiometric nanoensemble-functionalized Surface-Enhanced Raman Spectroscopy (SERS) chip is proposed and an ultrasensitive "sandwich" structure introduced for the detection of 5-HT to achieve early diagnosis of colon cancer. The SERS-based chip contains core-shell SERS active substrates coded by different Raman tags with Raman-silent region peaks (Au@EBP@Au NR arrays and Au@MBN@Ag NPs) and then identify-function molecule modification to construct the "sandwich" structure (Au@EBP@Au NR arrays/5-HT/Au@MBN@Ag NPs). Au@EBP@Au NR arrays showed excellent SERS performance, including good uniformity with an RSD of 5.53% and an enhancement factor (EF) of 2.13 × 107. The intensity ratio of the peaks in the Raman silent region was proportional to the concentration of 5-HT in the range 5 × 10-7-1 × 10-3 M, with a detection limit (LOD) of 4.9 × 10-9 M. Excellent assay accuracy was also demonstrated, with recoveries in the range 96.80% to 104.96%. Finally, we found that 5-HT expression levels in normal human sera were much lower than those in colon cancer patients by using a SERS-based chip for determination of the concentration of 5-HT in clinical colon cancer serum. This result suggested that the proposed approach has potential for detecting 5-HT by ratiometric SERS-based chips for early diagnosis of colon cancer.


Assuntos
Nanopartículas Metálicas , Serotonina , Humanos , Nanopartículas Metálicas/química , Ouro/química , Prata/química , Análise Espectral Raman/métodos
15.
Clin Oral Investig ; 27(11): 6891-6902, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37821654

RESUMO

OBJECTIVE: The purpose in the study was to evaluate the effect of biogenic silver nanoparticles (Ag NPs) synthesized by the green synthesis method on dentin bond strength in three different universal adhesives and investigate their antibiofilm activity against Streptococcus mutans (S. mutans). MATERIALS AND METHODS: Three different universal adhesives (single bond universal, all-bond universal, and clearfil universal) were used in this study. Ag NPs were synthesized using rose hip (Rosa canina) extract as a reducing and stabilizing agent and they were characterized with STEM, UV-vis spectrophotometer, DLS, and zeta potential. Ag NPs were added to the adhesive resins at a rate of 0.05% (w/w), and their homogeneous distribution in the adhesive was determined using EDX spectrometry. Samples in all groups were tested at baseline-after 5000 and 10,000 thermal cycles. Adhesive composite discs were used for the live/dead analysis of S. mutans, MTT metabolic activity test, lactic acid production, and determination of colony-forming unit (CFU) values (n = 3). Ninety extracted caries-free human third molars were used to determine microtensile bond strength (µTBS) (n = 10). After the universal adhesive was applied to the dentin surface, composite resin (Z550 XT, 3 M ESPE, USA) was placed and sections were taken to form a composite-dentin stick of 1 mm × 1 mm wideness and 8-mm length. The sticks were broken at a rate of 1 mm/min under uniaxial tension in a universal testing machine, and the failure modes were determined by SEM. One-way analysis of variance (ANOVA) for antibacterial tests and two-way analysis of variance for µTBS tests were performed (p < 0.05). RESULTS: All universal adhesive groups containing Ag NPs showed higher antibacterial activity than control groups without Ag NPs (p < 0.05). There was a statistically significant difference in the live/dead assay analysis, MTT metabolic activity test, lactic acid production, and CFU values in the thermal cycled Ag NPs groups (p < 0.05). Antibacterial activity decreased in groups containing Ag NPs subjected to 10,000 thermal cycles. The highest lactic acid production 11.06 (± 0.629) and CFUs 7.61 (± 0.304), live bacteria 31.13 (± 0.466), and S. mutans MTT metabolic activity 0.29 (± 0.376) at AU (All-Bond Universal-Ag NPs) 10,000 thermal cycles group. There was no difference in µTBS values between the initial and 5000 thermal cycle groups, there was a difference between the 10,000 thermal cycle groups. The CU (Clearfil Universal-Ag NPs) group subjected to 10,000 thermal cycles showed lower µTBS 11.1 (± 3.2). CONCLUSION: In conclusion, universal adhesives containing biogenic Ag NPs showed higher antibacterial activity than the control groups and did not reduce the µTBS. CLINICAL RELEVANCE: Antibacterial universal adhesives can contribute to restoration success in clinical applications by reducing residual bacteria and preventing secondary caries formation.


Assuntos
Anti-Infecciosos , Colagem Dentária , Cárie Dentária , Nanopartículas Metálicas , Rosa , Humanos , Cimentos Dentários/química , Adesivos Dentinários/química , Prata , Cimentos de Resina/química , Colagem Dentária/métodos , Dentina , Antibacterianos , Ácido Láctico , Resistência à Tração , Teste de Materiais , Adesivos
16.
Int J Mol Sci ; 24(4)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36834941

RESUMO

Research on the use of different parts of the Moringa oleifera plant as a nutritional and pharmaceutical resource for human and animals has increased in recent years. This study aimed to investigate the chemical composition and the TPCs and TFCs of Moringa leaves, the antimicrobial activities of Moringa successive ethanolic, aqueous, crude aqueous extracts, and green-chemically synthesized characterized Ag-NPs. The results indicated that the ethanolic extract recorded the highest activity against E. coli. On the other side, the aqueous extract showed higher activity, and its effects ranged from 0.03 to 0.33 mg/mL against different strains. The MIC values of Moringa Ag-NPs against different pathogenic bacteria ranged from 0.05 mg/mL to 0.13 mg/mL, and the activity of the crude aqueous extract ranged from 0.15 to 0.83 mg/mL. For the antifungal activity, the ethanolic extract recorded the highest activity at 0.04 mg/mL, and the lowest activity was recorded at 0.42 mg/mL. However, the aqueous extract showed effects ranging from 0.42 to 1.17 mg/mL. Moringa Ag-NPs showed higher activity against the different fungal strains than the crude aqueous extract, and they ranged from 0.25 to 0.83 mg/mL. The MIC values of the Moringa crude aqueous extract ranged from 0.74 to 3.33 mg/mL. Moringa Ag-NPs and their crude aqueous extract may be utilized to boost antimicrobial attributes.


Assuntos
Anti-Infecciosos , Moringa oleifera , Humanos , Animais , Moringa oleifera/química , Escherichia coli , Anti-Infecciosos/análise , Etanol/análise , Água/análise , Folhas de Planta/química , Extratos Vegetais/química
17.
Int J Mol Sci ; 24(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36835640

RESUMO

Silver nanoparticles (Ag-NPs) demonstrate unique properties and their use is exponentially increasing in various applications. The potential impact of Ag-NPs on human health is debatable in terms of toxicity. The present study deals with MTT(3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium-bromide) assay on Ag-NPs. We measured the cell activity resulting from molecules' mitochondrial cleavage through a spectrophotometer. The machine learning models Decision Tree (DT) and Random Forest (RF) were utilized to comprehend the relationship between the physical parameters of NPs and their cytotoxicity. The input features used for the machine learning were reducing agent, types of cell lines, exposure time, particle size, hydrodynamic diameter, zeta potential, wavelength, concentration, and cell viability. These parameters were extracted from the literature, segregated, and developed into a dataset in terms of cell viability and concentration of NPs. DT helped in classifying the parameters by applying threshold conditions. The same conditions were applied to RF to extort the predictions. K-means clustering was used on the dataset for comparison. The performance of the models was evaluated through regression metrics, viz. root mean square error (RMSE) and R2. The obtained high value of R2 and low value of RMSE denote an accurate prediction that could best fit the dataset. DT performed better than RF in predicting the toxicity parameter. We suggest using algorithms for optimizing and designing the synthesis of Ag-NPs in extended applications such as drug delivery and cancer treatments.


Assuntos
Nanopartículas Metálicas , Linhagem Celular , Aprendizado de Máquina , Nanopartículas Metálicas/toxicidade , Extratos Vegetais , Prata/toxicidade
18.
Molecules ; 28(9)2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37175344

RESUMO

Silver nanoparticles (Ag-NPs) are attracting great attention for their use in various applications, along with methods for their green and facile production. In this study, we present a new eco-friendly approach based on the use of Euphorbia balsamifera extract (EBE) in the green synthesis of silver nanoparticles (Ag-NPs), which are then applied as a reducing and stabilizing agent for the efficient removal of water-based reactive dyes such as bromocresol green (BCG) and bromophenol blue (BPB). The as-prepared Ag-NPs are quasi-spherical in shape, with an average diameter of 20-34 nm. Diverse characterization methods, including X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) analysis, were used to analyze these Ag-NPs. The results reveal that water-soluble biomolecules in the Euphorbia balsamifera extract play an important role in the formation of the Ag-NPs. The removal of toxic dyes was studied under varied operational parameters such as Ag-NP dosage, initial dye concentration, pH, stirring time, and temperature. Under the optimum investigated conditions, nearly 99.12% and 97.25% of the bromocresol green and bromophenol blue dyes, respectively, were removed. Both BCG and BPB adsorption were found to adhere to pseudo-second-order kinetics (r22 = 1 and 0.995) and fit the Langmuir isotherm models well (R12 = 0.998 and 0.994), with maximal monolayer adsorption capacities of 20.40 and 41.03 mg/g, respectively. Their adsorption processes were observed to be intrinsically endothermic. The results confirm the potential of the Euphorbia balsamifera extract as a low-cost, nontoxic, and eco-friendly natural resource for the synthesis of Ag-NPs that may be useful in the remediation of hazardous dye-contaminated water sources.


Assuntos
Euphorbia , Nanopartículas Metálicas , Corantes , Azul de Bromofenol , Espectroscopia de Infravermelho com Transformada de Fourier , Euphorbia/química , Prata/química , Verde de Bromocresol , Nanopartículas Metálicas/química , Água/química , Extratos Vegetais/química
19.
Molecules ; 28(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36838687

RESUMO

It is essential to estimate the indoor pesticides/insecticides exposure risk since reports show that 80% of human exposure to pesticides occurs indoors. As one of the three major contamination sources, surface collected pesticides contributed significantly to this risk. Here, a highly sensitive liquid freestanding membrane (FSM) SERS method based on iodide modified silver nanoparticles (Ag NPs) was developed for quantitative detection of insecticide deltamethrin (DM) residues in solution phase samples and on surfaces with good accuracy and high sensitivity. The DM SERS spectrum from 500 to 2500 cm-1 resembled the normal Raman counterpart of solid DM. Similar bands at 563, 1000, 1165, 1207, 1735, and 2253 cm-1 were observed as in the literature. For the quantitative analysis, the strongest peak at 1000 cm-1 that was assigned to the stretching mode of the benzene ring and the deformation mode of C-C was selected. The peak intensity at 1000 cm-1 and the concentration of DM showed excellent linearity from 39 to 5000 ppb with a regression equation I = 649.428 + 1.327 C (correlation coefficient R2 = 0.991). The limit of detection (LOD) of the DM was found to be as low as 11 ppb. Statistical comparison between the proposed and the HPLC methods for the analysis of insecticide deltamethrin (DM) residues in solution phase samples showed no significant difference. DM residue analysis on the surface was mimicked by dropping DM pesticide on the glass surface. It is found that DM exhibited high residue levels up to one week after exposure. This proposed SERS method could find application in the household pesticide residues analysis.


Assuntos
Inseticidas , Nanopartículas Metálicas , Resíduos de Praguicidas , Praguicidas , Humanos , Inseticidas/química , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Prata/química , Praguicidas/análise , Resíduos de Praguicidas/análise
20.
Molecules ; 28(16)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37630409

RESUMO

This study focuses on the fabrication of fiber membranes containing different concentrations of AgNO3 via the electrospinning technique. The AgNO3 present in the fibers is subsequently reduced to silver nanoparticles (Ag NPs) through UV irradiation. The resulting nanofiber film is characterized using scanning electron microscopy, X-ray diffraction, and evaluations of its anti-UV and anti-electromagnetic radiation properties. Experimental results demonstrate that increasing the AgNO3 content initially decreases and then increases the fiber diameter and fiber diameter deviation. Under UV light, the nanofibers fuse and bond, leading to an increase in the fiber diameter. AgNO3 is effectively reduced to Ag NPs after UV irradiation for more than 60 min, as confirmed by the characteristic diffraction peaks of Ag NPs in the XRD spectrum of the irradiated AgNO3/PVB fibers. The nanofiber film containing AgNO3 exhibits superior anti-UV performance compared to the film containing AgNO3-derived Ag NPs. The anti-electromagnetic radiation performances of the nanofiber films containing AgNO3 and AgNO3-derived Ag NPs are similar, but the nanofiber film containing AgNO3-derived Ag NPs exhibits higher performance at approximately 2.5 GHZ frequency. Additionally, at an AgNO3 concentration of less than 0.5 wt%, the anti-electromagnetic radiation performance is poor, and the shielding effect of the nanofiber film on medium- and low-frequency electromagnetic waves surpasses that on high-frequency waves. This study provides guidance for the preparation of polyvinyl butyral nanofibers, Ag NPs, and functional materials with anti-ultraviolet and anti-electromagnetic radiation properties.

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