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1.
J Environ Sci (China) ; 148: 437-450, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095178

RESUMO

For environmental applications, it is crucial to rationally design and synthesize photocatalysts with positive exciton splitting and interfacial charge transfer. Here, a novel Ag-bridged dual Z-scheme Ag/g-C3N4/CoNi-LDH plasmonic heterojunction was successfully synthesized using a simple method, with the goal of overcoming the common drawbacks of traditional photocatalysts such as weak photoresponsivity, rapid combination of photo-generated carriers, and unstable structure. These materials were characterized by XRD, FT-IR, SEM, TEM UV-Vis/DRS, and XPS to verify the structure and stability of the heterostructure. The pristine LDH, g-C3N4, and Ag/g-C3N4/CoNi-LDH composite were investigated as photocatalysts for water remediation, an environmentally motivated process. Specifically, the photocatalytic degradation of tetracycline was studied as a model reaction. The performance of the supports and composite catalyst were determined by evaluating both the degradation and adsorption phenomenon. The influence of several experimental parameters such as catalyst loading, pH, and tetracycline concentration were evaluated. The current study provides important data for water treatment and similar environmental protection applications.


Assuntos
Nanocompostos , Fotólise , Prata , Poluentes Químicos da Água , Purificação da Água , Nanocompostos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Prata/química , Catálise , Nitrilas/química , Compostos de Nitrogênio/química , Adsorção , Grafite
2.
Mikrochim Acta ; 191(9): 545, 2024 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-39158763

RESUMO

An electrochemical biosensor based on dual-amplified nucleic acid mode and biocatalytic silver deposition was constructed using catalytic hairpin assembly-hybrid chain reaction (CHA-HCR). The electrochemical detection of silver on the electrode by linear sweep voltammetry (LSV) can be utilized to quantitatively measure miR-205-5p since the amount of silver deposited on the electrode is proportional to the target nucleic acid. The current response values exhibit strong linearity with the logarithm of miR-205-5p concentrations ranging from 0.1 pM to 10 µM, and the detection limit is 28 fM. A consistent trend was found in the results of the qRT-PCR and electrochemical biosensor techniques, which were employed to determine the total RNA recovered from cells, respectively. Moreover, the constructed sensor was used to assess miR-205-5p on various cell counts, and the outcomes demonstrated the excellent analytical efficiency of the proposed strategy. The recoveries ranged from 97.85% to 115.3% with RSDs of 2.251% to 4.869% in human serum samples. Our electrochemical biosensor for miR-205-5p detection exhibits good specificity, high sensitivity, repeatability, and stability. It is a potentially useful sensing platform for tumor diagnosis and tumor type identification in clinical settings.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Limite de Detecção , MicroRNAs , Prata , Técnicas Biossensoriais/métodos , Humanos , MicroRNAs/sangue , MicroRNAs/análise , Prata/química , Técnicas Eletroquímicas/métodos , Eletrodos , Técnicas de Amplificação de Ácido Nucleico/métodos
3.
ACS Sens ; 9(8): 4295-4304, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39143674

RESUMO

Plasmonic Au-Ag nanostars are excellent surface-enhanced Raman scattering (SERS) probes due to bimetallic coupling and the tip effect. However, the existing preparation methods of AuAg nanostars cannot achieve controlled growth of the Ag layer on the branches of nanostars and so cannot display their SERS to the maximum extent, thus limiting its sensitivity in biosensing. Herein, a novel strategy "PEI (polyethylenimine)-guided Ag deposition method" is proposed for synthesizing AuAg core-shell nanostars (AuAg@Ag NS) with a tunable distribution of the Ag layer from the core to the tip, which offers an avenue for investigating the correlation between SERS efficiency and the extent of spread of the Ag layer. It is found that AuAg@Ag NS with a Ag layer coated the whole branch has the strongest SERS performance because the coupling between the tips and Ag layer is maximized. Meanwhile, as a completely closed core-shell structure, AuAg@Ag NS can confine and anchor 4-ATP inside the Ag layer to avoid an unstable SERS signal. By connecting the aptamer, a reliable internal standard nanoprobe with a SERS enhancement factor (EF) up to 1.86 × 108 is prepared. Okada acid is detected through competitive adsorption of this SERS probes, and the detection limit is 36.6 pM. The results gain fundamental insights into tailoring the nanoparticle morphologies and preparation of internal standard nanoprobes and also provide a promising avenue for marine toxin detection in food safety.


Assuntos
Ouro , Nanopartículas Metálicas , Ácido Okadáico , Frutos do Mar , Prata , Análise Espectral Raman , Prata/química , Análise Espectral Raman/métodos , Ouro/química , Ácido Okadáico/análise , Frutos do Mar/análise , Nanopartículas Metálicas/química , Animais , Polietilenoimina/química , Limite de Detecção , Aptâmeros de Nucleotídeos/química , Contaminação de Alimentos/análise
4.
BMJ Open ; 14(8): e077902, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39142672

RESUMO

OBJECTIVE: To evaluate the effects of silver and iodine dressings on healing time, healing rate, exudate amount, pain and anti-infective efficacy. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Databases including PubMed, Cochrane Library, Embase, Web of Science and CINAHL were surveyed up to May 2024. ELIGIBILITY CRITERIA: Randomised controlled trials comparing silver and iodine dressings on wound healing in humans. DATA EXTRACTION AND SYNTHESIS: Evidence certainty was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation approach. Data extraction was done independently by two reviewers, with the risk of bias assessed using the Cochrane tool. Narrative synthesis was performed to evaluate the effects of silver and iodine dressings on healing time, healing rate, pain, exudate amount and anti-infective efficacy. Meta-analysis using Review Manager V.5.4 calculated standardised mean differences for healing time and relative risks for rate to quantify the impacts of the treatments. RESULTS: 17 studies (18 articles) were included. The meta-analysis indicated that silver dressings significantly reduced healing time compared with iodine dressings (SMD=-0.95, 95% CI -1.62 to -0.28, I2=92%, p=0.005, moderate-quality evidence), with no significant difference in enhancing healing rate (RR=1.29, 95% CI 0.90 to 1.85, I2=91%, p=0.16, low-quality evidence). Based on low-quality evidence, for exudate amount (3/17), 66.7% (2/3) of the studies favoured silver dressings over iodine in reducing exudate volume. For pain (7/17), 57.1% (4/7) of the studies reported no significant difference between silver and iodine dressings, while 42.9% (3/7) studies indicated superior pain relief with silver dressings. For anti-infective efficacy (11/13), 54.5% (6/11) of the studies showed equivalence between silver and iodine dressings, while 36.4% (4/11) suggested greater antibacterial efficacy for silver. CONCLUSION: Silver dressings, demonstrating a comparable healing rate to iodine dressings, significantly reduce healing time, suggesting their potential as a superior adjunct in wound care. PROSPERO REGISTRATION NUMBER: CRD42020199602.


Assuntos
Anti-Infecciosos Locais , Bandagens , Iodo , Cicatrização , Humanos , Cicatrização/efeitos dos fármacos , Iodo/uso terapêutico , Anti-Infecciosos Locais/uso terapêutico , Prata/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Sci Rep ; 14(1): 19163, 2024 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-39160246

RESUMO

The effect of silver nanoparticles (Ag NPs) obtained in the presence of royal jelly (RJ) on the growth of yeast Candida guilliermondii NP-4, on the total and H+-ATPase activity, as well as lipid peroxidation process and antioxidant enzymes (superoxide dismutase (SOD), catalase) activity was studied. It has been shown that RJ-mediated Ag NPs have a fungicide and fungistatic effects at the concentrations of 5.4 µg mL-1 and 27 µg mL-1, respectively. Under the influence of RJ-mediated Ag NPs, a decrease in total and H+-ATPase activity in yeast homogenates by ~ 90% and ~ 80% was observed, respectively. In yeast mitochondria total and H+-ATPase activity depression was detected by ~ 80% and ~ 90%, respectively. The amount of malondialdehyde in the Ag NPs exposed yeast homogenate increased ~ 60%, the catalase activity increased ~ 70%, and the SOD activity-~ 30%. The obtained data indicate that the use of RJ-mediated Ag NPs have a diverse range of influence on yeast cells. This approach may be important in the field of biomedical research aimed at evaluating the development of oxidative stress in cells. It may also contribute to a more comprehensive understanding of antimicrobial properties of RJ-mediated Ag NPs and help control the proliferation of pathogenic fungi.


Assuntos
Candida , Ácidos Graxos , Nanopartículas Metálicas , Prata , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/química , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Ácidos Graxos/metabolismo , Ácidos Graxos/química , Antifúngicos/farmacologia , Antifúngicos/química , Testes de Sensibilidade Microbiana , Superóxido Dismutase/metabolismo , Antioxidantes/farmacologia , Antioxidantes/química , Estresse Oxidativo/efeitos dos fármacos , Catalase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos
6.
Int J Nanomedicine ; 19: 8271-8284, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39161360

RESUMO

Purpose: Development of SERS-based Raman nanoprobes can detect the misfolding of Amyloid beta (Aß) 42 peptides, making them a viable diagnostic technique for Alzheimer's disease (AD). The detection and imaging of amyloid peptides and fibrils are expected to help in the early identification of AD. Methods: Here, we propose a fast, easy-to-use, and simple scheme based on the selective adsorption of Aß42 molecules on SERS active gold nanoprobe (RB-AuNPs) of diameter 29 ± 3 nm for Detection of Alzheimer's Disease Biomarkers. Binding with the peptides results in a spectrum shift, which correlates with the target peptide. We also demonstrated the possibility of using silver nanoparticles (AgNPs) as precursors for the preparation of a SERS active nanoprobe with carbocyanine (CC) dye and AgNPs known as silver nanoprobe (CC-AgNPs) of diameter 25 ± 4 nm. Results: RB-AuNPs probe binding with the peptides results in a spectrum shift, which correlates with the target peptide. Arginine peak appears after the conjugation confirms the binding of Aß 42 with the nanoprobe. Tyrosine peaks appear after conjugated Aß42 with CC-AgNPs providing binding of the peptide with the probe. The nanoprobe produced a strong, stable SERS signal. Further molecular docking was utilized to analyse the interaction and propose a structural hypothesis for the process of binding the nanoprobe to Aß42 and Tau protein. Conclusion: This peptide-probe interaction provides a general enhancement factor and the molecular structure of the misfolded peptides. Secondary structural information may be obtained at the molecular level for specific residues owing to isotope shifts in the Raman spectra. Conjugation of the nanoprobe with Aß42 selectively detected AD in bodily fluids. The proposed nanoprobes can be easily applied to the detection of Aß plaques in blood, saliva, and sweat samples.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Biomarcadores , Ouro , Nanopartículas Metálicas , Simulação de Acoplamento Molecular , Fragmentos de Peptídeos , Prata , Análise Espectral Raman , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/metabolismo , Análise Espectral Raman/métodos , Peptídeos beta-Amiloides/análise , Peptídeos beta-Amiloides/química , Nanopartículas Metálicas/química , Ouro/química , Prata/química , Humanos , Biomarcadores/análise , Adsorção , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/química
7.
ACS Appl Bio Mater ; 7(8): 5530-5540, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39093994

RESUMO

This study reports on the modification of bacterial cellulose (BC) membranes produced by static fermentation of Komagataeibacter xylinus bacterial strains with graphene oxide-silver nanoparticles (GO-Ag) to yield skin wound dressings with improved antibacterial properties. The GO-Ag sheets were synthesized through chemical reduction with sodium citrate and were utilized to functionalize the BC membranes (BC/GO-Ag). The BC/GO-Ag composites were characterized to determine their surface charge, morphology, exudate absorption, antimicrobial activity, and cytotoxicity by using fibroblast cells. The antimicrobial activity of the wound dressings was assessed against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The results indicate that the BC/GO-Ag dressings can inhibit ∼70% of E. coli cells. Our findings also revealed that the porous BC/GO-Ag antimicrobial dressings can efficiently retain 94% of exudate absorption after exposure to simulated body fluid (SBF) for 24 h. These results suggest that the dressings could absorb excess exudate from the wound during clinical application, maintaining adequate moisture, and promoting the proliferation of epithelial cells. The BC/GO-Ag hybrid materials exhibited excellent mechanical flexibility and low cytotoxicity to fibroblast cells, making excellent wound dressings able to control bacterial infectious processes and promote the fast healing of dermal lesions.


Assuntos
Antibacterianos , Materiais Biocompatíveis , Celulose , Escherichia coli , Grafite , Teste de Materiais , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Prata , Staphylococcus aureus , Cicatrização , Grafite/química , Grafite/farmacologia , Prata/química , Prata/farmacologia , Cicatrização/efeitos dos fármacos , Celulose/química , Celulose/farmacologia , Nanopartículas Metálicas/química , Antibacterianos/química , Antibacterianos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Tamanho da Partícula , Pseudomonas aeruginosa/efeitos dos fármacos , Gluconacetobacter xylinus/química , Humanos , Camundongos , Bandagens , Animais
8.
J Environ Manage ; 367: 122046, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39094410

RESUMO

Rational fabrication of core-shell photocatalysts to hamper the charge recombination is extraordinarily essential to enhance photocatalytic activity. In this work, core-shell Ag@NH2-UiO-66 (Ag@NU) Schottky heterojunctions with low Ag content (1 wt%) were constructed by a two-step solvothermal method and adopted for Cr(VI) reduction under LED light. Typically, the one with the Ag: NH2-UiO-66 mass ratio (1 : 100) led to 100% Cr(VI) removal within 1 h, superior to bare NH2-UiO-66 and Ag/NH2-UiO-66 (Ag was directly decorated on NH2-UiO-66 surface). The enhanced photocatalytic activity was related to the migration of the electrons on the CB of NH2-UiO-66 to Ag NPs through a Schottky barrier, and thus the undesired charge carriers recombination was avoided. This result was also evidenced by Density functional theory (DFT) calculations. The computational simulations indicate that the introduction of Ag effectively narrowed the band gap of NH2-UiO-66, facilitating the transfer of photo-generated electrons, expanding the light absorption area, and significantly enhancing photocatalytic efficiency. Most importantly, such a core-shell structure can inhibit the formation of •O2-, letting the direct Cr(VI) reduction by photo-excited e-. In addition, this structure can also protect Ag from being oxidized by O2. Ten cyclic tests evidenced the Ag@NU had excellent chemical and structural stability. This research offers a novel strategy for regulating the Cr(VI) reduction by establishing core-shell photocatalytic materials.


Assuntos
Cromo , Catálise , Cromo/química , Prata/química
9.
Biomed Mater ; 19(5)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39094626

RESUMO

Because of its superior strength, esthetic properties, and excellent biocompatibility, zirconia is preferred for dental prosthetic such as crowns and bridges. However, zirconia crowns and bridges are susceptible to secondary caries owing to margin leakage. Silver is a well-known antibacterial agent, making it a desirable additive to zirconia crowns and bridges for secondary caries prevention. This study focuses on imparting zirconia composite with antibacterial properties to enhance its protective capacity in dental restorations. We used the sol-gel method to dope Ag into zirconia. Silver-doped zirconia powders were prepared at Zr:Ag molar ratios of 100:0,100:0.1, 100:0.5, 100:1, 100:3, and 100:5 (respective samples denoted as Ag-0, Ag-0.1, Ag-0.5, Ag-1, Ag-3, and Ag-5) and were subjected to firing at various temperatures (400 °C-1000 °C). We performed x-ray diffraction to investigate the crystal phase of these powders and x-ray fluorescence and field emission scanning electron microscopy to analyze their elemental composition and surface morphology, respectively. Moreover, we performed spectrophotometry to determine theL*a*b* color values, conducted dissolution tests, and quantified the Ag content through inductively coupled plasma optical emission spectroscopy. In addition, we studied the antibacterial activity of the samples. Analyses of the samples fired at ⩽600 °C revealed a predominantly white to grayish-white coloration and a tetragonal crystal phase. Firing at ⩾700 °C resulted in gray or dark gray coloration and a monoclinic crystal phase. The Ag content decreased after firing at 900 °C or 1000 °C. Ag-0.5 and above exhibited antibacterial activity against bothEscherichia coliandStaphylococcus aureus. Therefore, the minimum effective silver-doped zirconia sample was found to be Ag-0.5. This study allows the exploration of the antimicrobial potential of silver-doped zirconia materials in dental applications such as prosthdontical lining materials, promoting the development of innovative restorations with protective capacity against secondary caries.


Assuntos
Antibacterianos , Teste de Materiais , Prata , Difração de Raios X , Zircônio , Zircônio/química , Prata/química , Prata/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Materiais Dentários/química , Materiais Dentários/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Pós , Propriedades de Superfície , Escherichia coli/efeitos dos fármacos , Humanos
10.
Int J Mol Sci ; 25(15)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39126001

RESUMO

Breast cancer is the most diagnosed type of cancer worldwide and the second cause of death in women. Triple-negative breast cancer (TNBC) is the most aggressive, and due to the lack of specific targets, it is considered the most challenging subtype to treat and the subtype with the worst prognosis. The present study aims to determine the antitumor effect of beta-D-glucose-reduced silver nanoparticles (AgNPs-G) in a murine model of TNBC, as well as to study its effect on the tumor microenvironment. In an airbag model with 4T1 tumor cell implantation, the administration of AgNPs-G or doxorubicin showed antitumoral activity. Using immunohistochemistry it was demonstrated that treatment with AgNPs-G decreased the expression of PCNA, IDO, and GAL-3 and increased the expression of Caspase-3. In the tumor microenvironment, the treatment increased the percentage of memory T cells and innate effector cells and decreased CD4+ cells and regulatory T cells. There was also an increase in the levels of TNF-α, IFN-γ, and IL-6, while TNF-α was increased in serum. In conclusion, we suggest that AgNPs-G treatment has an antitumor effect that is demonstrated by its ability to remodel the tumor microenvironment in mice with TNBC.


Assuntos
Glucose , Nanopartículas Metálicas , Prata , Neoplasias de Mama Triplo Negativas , Microambiente Tumoral , Animais , Microambiente Tumoral/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Prata/química , Nanopartículas Metálicas/química , Feminino , Camundongos , Glucose/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Doxorrubicina/farmacologia , Humanos
11.
Anal Chem ; 96(32): 13042-13049, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39092994

RESUMO

Influenza (flu) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exhibit similar clinical symptoms, complicating the diagnosis and clinical management of these critical respiratory infections. Thus, there is an urgent need for rapid on-site detection technologies that can simultaneously detect SARS-CoV-2 and influenza A viruses. Here, we have developed the first platform that combines in situ sampling with immune swabs and multichannel surface-enhanced Raman spectroscopy (SERS) for simultaneous screening of these two respiratory viruses in a single assay. A seed-mediated growth method was used to assemble a number of silver spheres on the surface of Fe3O4@SiO2 spheres, which not only creates extensive Raman hotspots but also provides numerous sites for Raman signaling molecules, enhancing the sensing sensitivity. Integrating two specific Raman signaling molecules into the nanospheres allows for the parallel detection of both viruses, improving the efficiency of SERS signal read-out. Rapid quantitative screening of both SARS-CoV-2 and H1N1 is achievable within 15 min, with detection limits of 7.76, and 8.13 pg·mL-1 for their respective target proteins. The platform demonstrated excellent performance in testing and analyzing 98 clinical samples (SARS-CoV-2:50; influenza A:48), achieving sensitivities of 88.00, and 95.83% for SARS-CoV-2 and influenza A, respectively. Pearson's correlation analysis revealed a significant correlation with the clinical CT values (P < 0.0001), underscoring the great potential of this platform for the early, rapid, and simultaneous diagnostic discrimination of multiple pathogens.


Assuntos
COVID-19 , Vírus da Influenza A , SARS-CoV-2 , Prata , Análise Espectral Raman , Análise Espectral Raman/métodos , SARS-CoV-2/isolamento & purificação , Humanos , COVID-19/diagnóstico , COVID-19/virologia , Prata/química , Vírus da Influenza A/isolamento & purificação , Dióxido de Silício/química , Influenza Humana/diagnóstico , Influenza Humana/virologia , Nanopartículas Metálicas/química
12.
Sci Rep ; 14(1): 18544, 2024 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-39122867

RESUMO

Breast cancer is one of cancer's most deadly varieties. Its variability makes the development of personalized therapies very difficult. Therefore, improvement of classic chemotherapy is still one of the important challenges of cancer research. We addressed this issue applying nanotechnology to verify the influence of silver nanoparticles (AgNPs) on doxorubicin (DOX) anticancer activity and assess if the size of AgNPs affects their interactions with DOX. We employed a broad spectrum of biophysical methods, characterizing 5 and 50 nm AgNPs interactions with DOX using UV-Vis spectroscopy, dynamic light scattering, fluorescence spectroscopy, and atomic force microscopy imaging. Biological effects of observed AgNPs-DOX interactions were assessed utilizing MTT and 3D Matrigel assays on SKBR3 and MDA-MB-231 breast cancer cell lines. Obtained results indicate direct interactions between AgNPs and DOX. Furthermore, AgNPs size influences their interactions with DOX, as evidenced by differences in the heteroaggregates formation observed in biophysical experiments and further supported by in vitro biological assays. We detected reduction of tumor cell viability and/or colony sizes of the analyzed cancer cell lines, registering differences linked to the observed phenomenon. However, the effects may be limited to the outer borders of the tumor microenvironment as evidenced by the 3D model. Summing up, we observed diverse patterns of interactions and biological effects for different sizes of AgNPs with DOX providing insight how the nanoparticles' size affects their interactions with other biologically active compounds. Moreover, obtained data can be further used in experiments on the reduction of tumor size i.e. before the surgical intervention.


Assuntos
Doxorrubicina , Nanopartículas Metálicas , Tamanho da Partícula , Prata , Doxorrubicina/farmacologia , Doxorrubicina/química , Humanos , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia
13.
Sci Rep ; 14(1): 18870, 2024 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143137

RESUMO

The characteristics of dopamine self-polymerization were used to cover the nano-titanium dioxide (TiO2) surface and produce nano-titanium dioxide-polydopamine (TiO2-PDA). The reducing nature of dopamine was then used to reduce silver nitrate to silver elemental particles on the modified nano-titanium dioxide: The resulting TiO2-PDA-Ag nanoparticles were used as antimicrobial agents. Finally, the antibacterial agent was mixed with silicone to obtain an antibacterial silicone composite material. The composition and structure of antibacterial agents were analyzed by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron energy spectroscopy, and X-ray diffraction. Microscopy and the antibacterial properties of the silicone antibacterial composites were studied as well. The TiO2-PDA-Ag antimicrobial agent had good dispersion versus nano-TiO2. The three were strongly combined with obvious characteristic peaks. The antibacterial agents were evenly dispersed in silicone, and the silicone composite has excellent antibacterial properties. Bacillus subtilis (B. subtilis) adhesion was reduced from 246 × 104 cfu/cm2 to 2 × 104 cfu/cm2, and colibacillus (E. coli) reduced from 228 × 104 cfu/cm2 leading to bacteria-free adhesion.


Assuntos
Bacillus subtilis , Escherichia coli , Silicones , Prata , Titânio , Titânio/química , Titânio/farmacologia , Silicones/química , Prata/química , Prata/farmacologia , Escherichia coli/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Polímeros/química , Polímeros/farmacologia , Difração de Raios X , Testes de Sensibilidade Microbiana , Aderência Bacteriana/efeitos dos fármacos , Indóis
14.
Sci Rep ; 14(1): 18944, 2024 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-39147839

RESUMO

Bilharzia is a parasitic flatworm that causes schistosomiasis, a neglected tropical illness worldwide. Praziquantel (PZQ) is a commercial single treatment of schistosomiasis so alternative drugs are needed to get rid of its side effects on the liver. The current study aimed to estimate the effective role of Ficus carica nanoparticles (Fc-NPCs), silver nanoparticles (Ag-NPCs) and Ficus carica nanoparticles loaded on silver nanoparticles (Fc-Ag NPCs) on C57BL/6 black female mice infected by Schistosoma mansoni and treated with PZQ treatment. It was proved that schistosomiasis causes liver damage in addition to the PZQ is ineffective as an anti-schistosomiasis; it is recorded in the infected mice group and PZQ treated group as in liver function tests, oxidative stress markers & anti-oxidants, pro-inflammatory markers, pro-apoptotic and anti-apoptotic markers also in liver cells' DNA damage. The amelioration in all tested parameters has been clarified in nanoparticle-protected mice groups. The Fc-Ag NPCs + PZQ group recorded the best preemptive effects as anti-schistosomiasis. Fc-NPCs, Ag-NPCs and Fc-Ag NPCs could antagonize PZQ effects that were observed in amelioration of all tested parameters. The study showed the phytochemicals' nanoparticles groups have an ameliorated effect on the health of infected mice.


Assuntos
Ficus , Nanopartículas Metálicas , Praziquantel , Schistosoma mansoni , Esquistossomose mansoni , Prata , Animais , Ficus/química , Camundongos , Praziquantel/farmacologia , Feminino , Schistosoma mansoni/efeitos dos fármacos , Nanopartículas Metálicas/química , Prata/química , Prata/farmacologia , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/parasitologia , Camundongos Endogâmicos C57BL , Fígado/parasitologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cercárias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sinergismo Farmacológico , Nanopartículas/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Anti-Helmínticos/farmacologia , Anti-Helmínticos/química , Anti-Helmínticos/uso terapêutico
15.
J Hazard Mater ; 477: 135358, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39088958

RESUMO

To address the potential hazards of organophosphorus pesticides (OPs) residues in tea, an electrochemiluminescence (ECL) aptasensor based on functionalized nanomaterials was constructed in this work. Firstly, gold nanoparticles (AuNPs) were attached on the surface of multi-walled carbon nanotubes (MWCNTs) by the constant potential electrodeposition to form a compound, and it was utilized to provide excellent immobilization sites for complementary DNA (cDNA). Subsequently, composite nanomaterials were synthesized by a one-pot method with aminated Luminol/silver nanoparticles@silica nanospheres (NH2-Luminol/Ag@SiO2NSs). Finally, NH2-Luminol/Ag@SiO2NSs was combined with a malathion aptamer (Apt) to obtain signal probes (SPs) for the construction of an aptasensor. The aptasensor had a wide linear range (1×10-3-1×103 ng/mL) and a low limit of detection (LOD) (0.3×10-3 ng/mL). It had the virtues of high sensitivity, wonderful stability and excellent specificity, which could be used for the detection of malathion residue in tea. The work provides a proven way for the construction of a rapid and ultrasensitive aptasensor with low-cost.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Eletroquímicas , Ouro , Limite de Detecção , Medições Luminescentes , Luminol , Malation , Nanopartículas Metálicas , Dióxido de Silício , Prata , Chá , Malation/análise , Malation/química , Chá/química , Nanopartículas Metálicas/química , Luminol/química , Prata/química , Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , Dióxido de Silício/química , Ouro/química , Aptâmeros de Nucleotídeos/química , Resíduos de Praguicidas/análise , Nanotubos de Carbono/química , Contaminação de Alimentos/análise , Técnicas Biossensoriais/métodos
16.
Biosens Bioelectron ; 263: 116621, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39098283

RESUMO

Constructing label-free bivariate fluorescence biosensor would be intriguing and desired for the recognizable and accurate detection of two specific DNA segments, yet the design of functional DNA structures with low overlapped interference might be challenging. Herein in this work, a double-faced Janus DNA nanoarchitecture (JDNA) with bi-responsive recognition regions on opposite sides was assembled, which consisted of two substrate strands and two template strands for loading green-/red-emissive Ag nanoclusters (gAgNC and rAgNC) as bivariate signaling reporters. Of note, the hybridized double helix in the middle rationally oriented two flank faces and stabilized the rigid conformation of JDNA, while the template sequences of bicolor clusters were blocked to minimize non-specific background leakage. Upon inputting two targets, the discernible hairpins lost their hairpin structures due to forming two dsDNA complexes. They were executed to simultaneously invade JDNA for activating two individual target-recycled strand displacement (TRSD) events, guiding signal transduction and efficient amplification. Consequently, the clustering templates were unlocked via the tailored conformation switch of JDNA, in which gAgNC and rAgNC were in situ synthesized in two diagonal positions, thereby significantly emitting bi-responsive signal without cross interference. Benefited from the logic integration of double-faced JDNA and TRSD, a label-free, sensitive and specific bivariate fluorescence approach was developed, which would open a new avenue for the potential application in biosensing and bioanalysis.


Assuntos
Técnicas Biossensoriais , DNA , Nanopartículas Metálicas , Prata , Técnicas Biossensoriais/métodos , Prata/química , DNA/química , Nanopartículas Metálicas/química , Humanos , Espectrometria de Fluorescência/métodos , Nanoestruturas/química , Hibridização de Ácido Nucleico , Limite de Detecção , Fluorescência , Corantes Fluorescentes/química
17.
Nano Lett ; 24(33): 10016-10023, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39109676

RESUMO

Food safety is vital to human health, necessitating the development of nondestructive, convenient, and highly sensitive methods for detecting harmful substances. This study integrates cellulose dissolution, aligned regeneration, in situ nanoparticle synthesis, and structural reconstitution to create flexible, transparent, customizable, and nanowrinkled cellulose/Ag nanoparticle membranes (NWCM-Ag). These three-dimensional nanowrinkled structures considerably improve the spatial-electromagnetic-coupling effect of metal nanoparticles on the membrane surface, providing a 2.3 × 108 enhancement factor for the surface-enhanced Raman scattering (SERS) effect for trace detection of pesticides in foods. Notably, the distribution of pesticides in the apple peel and pulp layers is visualized through Raman imaging, confirming that the pesticides penetrate the peel layer into the pulp layer (∼30 µm depth). Thus, the risk of pesticide ingestion from fruits cannot be avoided by simple washing other than peeling. This study provides a new idea for designing nanowrinkled structures and broadening cellulose utilization in food safety.


Assuntos
Celulose , Inocuidade dos Alimentos , Nanopartículas Metálicas , Praguicidas , Análise Espectral Raman , Celulose/química , Praguicidas/análise , Praguicidas/química , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Prata/química , Malus/química , Humanos , Frutas/química , Nanotecnologia/métodos , Propriedades de Superfície , Contaminação de Alimentos/análise
18.
ACS Appl Bio Mater ; 7(8): 5057-5075, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39115261

RESUMO

Melanoma has gained considerable attention due to its high mortality and morbidity rate worldwide. The currently available treatment options are associated with several limitations such as nonspecificity, drug resistance, easy clearance, low efficacy, toxicity-related issues, etc. To this end, nanotechnology has garnered significant attention for the treatment of melanoma. In the present manuscript, we have demonstrated the in vitro and in vivo anticancer activity of silver nitroprusside nanoparticles (abbreviated as AgNNPs) against melanoma. The AgNNPs exhibit cytotoxicity against B16F10 cells, which has been investigated by several in vitro experiments including [methyl 3H]-thymidine incorporation assay, cell cycle and apoptosis analysis by flow cytometry, and ROS generation through DCFDA, DHE, and DAF2A reagents. Further, the internalization of nanoparticles was determined by ICPOES analysis, while their colocalization was analyzed by confocal microscopy. Additionally, JC-1 staining is performed to examine mitochondrial membrane potential (MMP). Cytoskeleton integrity was observed by phalloidin staining. Expression of different markers (Ki-67, cytochrome c, and E-cadherin) was checked using an immunofluorescence assay. The in vivo therapeutic efficacy of AgNNPs has been validated in the melanoma model established by inoculating B16F10 cells into the dorsal right abdomen of C57BL/6J mice. The intraperitoneal administration of AgNNPs reduced melanoma growth and increased the survivability of tumor-bearing mice. The in vivo immunofluorescence studies (Ki-67, CD31, and E-cadherin) and TUNEL assay support the inhibitory and apoptotic nature of AgNNPs toward melanoma, respectively. Furthermore, the various signaling pathways and molecular mechanisms involved in anticancer activity are evaluated by Western blot analysis. These findings altogether demonstrate the promising anticancer potential of AgNNPs toward melanoma.


Assuntos
Antineoplásicos , Apoptose , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Camundongos Endogâmicos C57BL , Nitroprussiato , Prata , Animais , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/química , Nitroprussiato/farmacologia , Nitroprussiato/química , Apoptose/efeitos dos fármacos , Prata/química , Prata/farmacologia , Proliferação de Células/efeitos dos fármacos , Tamanho da Partícula , Teste de Materiais , Melanoma/tratamento farmacológico , Melanoma/patologia , Nanopartículas Metálicas/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Nanopartículas/química , Sobrevivência Celular/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio/metabolismo , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Melanoma Experimental/metabolismo
19.
Sci Rep ; 14(1): 19013, 2024 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152125

RESUMO

The beekeeping industry plays a crucial role in local economies, contributing significantly to their growth. However, bee colonies often face the threat of American foulbrood (AFB), a dangerous disease caused by the Gram-positive bacterium Paenibacillus larvae (P. l.). While the antibiotic Tylosin has been suggested as a treatment, its bacterial resistance necessitates the search for more effective alternatives. This investigation focused on evaluating the potential of bee venom (BV) and silver nanoparticles (Ag NPs) as antibacterial agents against AFB. In vitro treatments were conducted using isolated AFB bacterial samples, with various concentrations of BV and Ag NPs (average size: 25nm) applied individually and in combination. The treatments were administered under both light and dark conditions. The viability of the treatments was assessed by monitoring the lifespans of treated bees and evaluating the treatment's efficiency within bee populations. Promising results were obtained with the use of Ag NPs, which effectively inhibited the progression of AFB. Moreover, the combination of BV and Ag NPs, known as bee venom/silver nanocomposites (BV/Ag NCs), significantly extended the natural lifespan of bees from 27 to 40 days. Notably, oral administration of BV in varying concentrations (1.53, 3.12, and 6.25 mg/mL) through sugary syrup doubled the bees' lifespan compared to the control group. The study established a significant correlation between the concentration of each treatment and the extent of bacterial inhibition. BV/Ag NCs demonstrated 1.4 times greater bactericidal efficiency under photo-stimulation with visible light compared to darkness, suggesting that light exposure enhances the effectiveness of BV/Ag NCs. The combination of BV and Ag NPs demonstrated enhanced antibacterial efficacy and prolonged honeybee lifespan. These results offer insights that can contribute to the development of safer and more efficient antibacterial agents for maintaining honeybee health.


Assuntos
Antibacterianos , Venenos de Abelha , Nanopartículas Metálicas , Paenibacillus larvae , Prata , Animais , Abelhas/microbiologia , Venenos de Abelha/farmacologia , Nanopartículas Metálicas/química , Prata/farmacologia , Prata/química , Antibacterianos/farmacologia , Paenibacillus larvae/efeitos dos fármacos , Longevidade/efeitos dos fármacos
20.
Sci Rep ; 14(1): 19009, 2024 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152164

RESUMO

The contamination of water sources by pharmaceutical pollutants presents significant environmental and health hazards, making the development of effective photocatalytic materials crucial for their removal. This research focuses on the synthesis of a novel Ag/CuS/Fe3O4 nanocomposite and its photocatalytic efficiency against tetracycline (TC) and diclofenac contaminants. The nanocomposite was created through a straightforward and scalable precipitation method, integrating silver nanoparticles (AgNPs) and copper sulfide (CuS) into a magnetite framework. Various analytical techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR),ultraviolet-visible spectrophotometry (UV-Vis) and energy-dispersive X-ray spectroscopy (EDS), were employed to characterize the structural and morphological properties of the synthesized material. The photocatalytic activity was tested by degrading tetracycline and diclofenac under visible light. Results indicated a marked improvement in the photocatalytic performance of the Ag/CuS/Fe3O4 nanocomposite (98%photodegradation of TC 60 ppm in 30 min) compared to both pure magnetite and CuS/Fe3O4. The enhanced photocatalytic efficiency is attributed to the synergistic interaction between AgNPs, CuS, and Fe3O4, which improves light absorption and charge separation, thereby increasing the generation of reactive oxygen species (ROS) and promoting the degradation of the pollutants. The rate constant k of photodegradation was about 0.1 min-1 for catalyst dosages 0.02 g. Also the effect of photocatalyst dose and concentration of TC and pH of solution was tested. The modified photocatalyst was also used for simultaneous photodegradation of TC and diclofenac successfully. This study highlights the potential of the Ag/CuS/Fe3O4 nanocomposite as an efficient and reusable photocatalyst for eliminating pharmaceutical pollutants from water.


Assuntos
Cobre , Diclofenaco , Óxido Ferroso-Férrico , Nanocompostos , Prata , Tetraciclina , Poluentes Químicos da Água , Diclofenaco/química , Nanocompostos/química , Tetraciclina/química , Catálise , Prata/química , Óxido Ferroso-Férrico/química , Poluentes Químicos da Água/química , Cobre/química , Nanopartículas Metálicas/química , Fotólise , Difração de Raios X , Luz
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