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1.
Mikrochim Acta ; 191(5): 249, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587558

RESUMO

17ß-Estradiol (E2) is the typical endocrine disruptor of steroidal estrogens and is widely used in animal husbandry and dairy processing. In the environment, even lower concentrations of E2 can cause endocrine dysfunction in organisms. Herein, we have developed a novel molecularly imprinted ratiometric fluorescent sensor based on SiO2-coated CdTe quantum dots (CdTe@SiO2) and 7-hydroxycoumarin with a post-imprint mixing strategy. The sensor selectively detected E2 in aqueous environments due to its two fluorescent signals with a self-correction function. The sensor has been successfully used for spiking a wide range of real water and milk samples. The results showed that the sensor exhibited good linearity over the concentration range 0.011-50 µg/L, obtaining satisfactory recoveries of 92.4-110.6% with precisions (RSD) < 2.5%. Moreover, this sensor obtained an ultra-low detection limit of 3.3 ng/L and a higher imprinting factor of 13.66. By using estriol (E3), as a supporting model, it was confirmed that a simple and economical ratiometric fluorescent construction strategy was provided for other hydrophobic substances.


Assuntos
Compostos de Cádmio , Pontos Quânticos , Animais , Leite , Fluorescência , Dióxido de Silício , Telúrio , Estradiol , Corantes
2.
Chem Commun (Camb) ; 60(34): 4581-4584, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38576349

RESUMO

A study of an integrated OPECT biosensor gate and the EC color-changing region on the same chip was carried out, achieving sensitive detection through bioetching-induced signal changes. Enzymatic bioetching enables specific alkaline phosphatase (ALP) detection by catalyzing the production of CdS, which modulates the channel current and generates a visual signal.


Assuntos
Fosfatase Alcalina , Técnicas Biossensoriais , Técnicas Eletroquímicas , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/análise , Transistores Eletrônicos , Compostos de Cádmio/química , Sulfetos/química , Processos Fotoquímicos
3.
J Hazard Mater ; 470: 134218, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38581878

RESUMO

The development of high-performance sensors for doxycycline (DOX) detection is necessary because its residue accumulation will cause serious harm to human health and the environment. Here, a novel tri-emission ratiometric fluorescence sensor was proposed by using "post-mixing" strategy of different emissions fluorescence molecularly imprinted polymers with salicylamide as dummy template (DMIPs). BSA was chosen as assistant functional monomer, and also acted as sensitizers for the aggregation-induced emission (AIE) effect of DOX. The blue-emitting carbon dots and the red-emitting CdTe quantum dots were separately introduced into DMIPs as the response signals. Upon DOX recognition within 2 min, blue and red fluorescence of the tri-emission DMIPs sensor were quenched while green fluorescence of DOX was enhanced, resulting in a wide range of color variations observed over bluish violet-rosered-light pink-orange-yellow-green with a detection limit of 0.061 µM. The sensor possessed highly selective recognition and was successfully applied to detect DOX in complicated real samples. Moreover, with the fluorescent color collection and data processing, the smartphone-assisted visual detection of the sensors showed satisfied sensitivity with low detection limit. This work provides great potential applications for rapid and visual detection of antibiotics in complex substrates.


Assuntos
Antibacterianos , Compostos de Cádmio , Doxiciclina , Impressão Molecular , Pontos Quânticos , Espectrometria de Fluorescência , Telúrio , Doxiciclina/análise , Doxiciclina/química , Pontos Quânticos/química , Telúrio/química , Antibacterianos/análise , Compostos de Cádmio/química , Limite de Detecção , Fluorescência , Carbono/química , Corantes Fluorescentes/química , Polímeros Molecularmente Impressos/química , Smartphone
4.
J Cardiothorac Surg ; 19(1): 188, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589945

RESUMO

Pulmonary embolism is the most common cardiovascular disease after myocardial infarction and stroke. Konstantinides (Eur Heart J 41(4):543-603, 2020) Current guidelines categorize patients with PE as being at low, intermediate, and high risk of early death, with the intermediate-risk group experiencing the greatest uncertainty regarding treatment recommendations. Rapid reduction of the thrombus load by thrombolysis significantly reduces symptoms and decreases mortality, but is accompanied by a high risk of bleeding. Meyer (N Engl J Med 370(15):1402-11, 2014) Mechanical thrombectomy (CDTE) have been proven safe and efficient, yet current ESC guidelines suggest the utilization of catheter interventions only for hypotensive patients with high bleeding risk, failed systemic thrombolysis, and cardiogenic shock or if a patient does not respond to conservative therapy Konstantinides (Eur Heart J 41(4):543-603, 2020). Here, we report a case of an intermediate-risk patient with pulmonary embolism who underwent thrombus aspiration and showed significant improvement in symptoms after treatment.


Assuntos
Compostos de Cádmio , Embolia Pulmonar , Pontos Quânticos , Trombose , Humanos , Trombectomia , Resultado do Tratamento , Telúrio , Embolia Pulmonar/terapia , Hemorragia , Terapia Trombolítica
5.
Anal Chim Acta ; 1304: 342579, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38637044

RESUMO

Plasmon enhanced fluorescent (PEF) with more "hot spots" play a critical role in signal amplified technology to avoid the intrinsic limitation of fluorophore which ascribed to a strong electromagnetic field at the tip structure. However, application of PEF technique to obtain a highly sensitive analysis of medicine was still at a very early stage. Herein, a simple but versatile Ag nanocubes (Agcubes)-based PEF sensor combined with aptamer (Agcubes@SiO2-QDs-Apt) was proposed for highly sensitive detection of berberine hydrochloride (BH). The distance between the plasma Agcubes and the red-emitted CdTe quantum dots (QDs) were regulated by the thickness of silica spacer. The three-dimensional finite-difference time-domain (3D-FDTD) simulation further revealed that Agcubes have a higher electromagnetic field than Ag nanospheres. Compared with PEF sensor, signal QDs-modified aptamer without Agcubes (QDs-Apt) showed a 10-fold higher detection limit. The linear range and detection limit of the Agcubes@SiO2-QDs-Apt were 0.1-100 µM, 87.3 nM, respectively. Furthermore, the PEF sensor was applied to analysis BH in the berberine hydrochloride tablets, compound berberine tablet and urine with good recoveries of 98.25-102.05%. These results demonstrated that the prepared PEF sensor has great potential for drug quality control and clinical analysis.


Assuntos
Aptâmeros de Nucleotídeos , Berberina , Compostos de Cádmio , Pontos Quânticos , Fluorescência , Pontos Quânticos/química , Compostos de Cádmio/química , Dióxido de Silício , Telúrio/química , Espectrometria de Fluorescência/métodos , Aptâmeros de Nucleotídeos/química , Limite de Detecção
6.
Int J Mol Sci ; 25(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38542058

RESUMO

Nanoparticles (NPs) represent a potential optoelectronic source capable of significantly boosting hydrogen production; however, their inevitable cytotoxicity may lead to oxidative damage of bacterial cell membranes. In this study, we employed non-photosynthetic Escherichia coli K-12 as a model organism and utilized self-assembled cadmium sulfide (CdS) nanoparticles to construct a low-toxicity and hydrogen-production-enhancing self-photosensitive hybrid system. To mitigate the cytotoxicity of CdS NPs and synthesize biocompatible CdS NPs on the cell surface, we employed engineered E. coli (efeB/OE) for bioremediation, achieving this goal through the overexpression of the peroxidase enzyme (EfeB). A comparative analysis with E. coli-CdS revealed a significant downregulation of genes encoding oxidative stress proteins in efeB/OE-CdS post-irradiation. Atomic force microscopy (AFM) confirmed the stability of bacterial cell membranes. Due to the enhanced stability of the cell membrane, the hydrogen yield of the efeB/OE-CdS system increased by 1.3 times compared to the control, accompanied by a 49.1% reduction in malondialdehyde (MDA) content. This study proposes an effective strategy to alleviate the toxicity of mixed biological nanoparticle systems and efficiently harness optoelectronic electrons, thereby achieving higher hydrogen production in bioremediation.


Assuntos
Compostos de Cádmio , Dermatite Fototóxica , Escherichia coli K12 , Nanopartículas , Humanos , Escherichia coli/genética , Nanopartículas/toxicidade , Sulfetos , Hidrogênio
7.
Phys Med Biol ; 69(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38471186

RESUMO

Following the rapid, but independent, diffusion of x-ray spectral and phase-contrast systems, this work demonstrates the first combination of spectral and phase-contrast computed tomography (CT) obtained by using the edge-illumination technique and a CdTe small-pixel (62µm) spectral detector. A theoretical model is introduced, starting from a standard attenuation-based spectral decomposition and leading to spectral phase-contrast material decomposition. Each step of the model is followed by quantification of accuracy and sensitivity on experimental data of a test phantom containing different solutions with known concentrations. An example of a micro CT application (20µm voxel size) on an iodine-perfusedex vivomurine model is reported. The work demonstrates that spectral-phase contrast combines the advantages of spectral imaging, i.e. high-Zmaterial discrimination capability, and phase-contrast imaging, i.e. soft tissue sensitivity, yielding simultaneously mass density maps of water, calcium, and iodine with an accuracy of 1.1%, 3.5%, and 1.9% (root mean square errors), respectively. Results also show a 9-fold increase in the signal-to-noise ratio of the water channel when compared to standard spectral decomposition. The application to the murine model revealed the potential of the technique in the simultaneous 3D visualization of soft tissue, bone, and vasculature. While being implemented by using a broad spectrum (pink beam) at a synchrotron radiation facility (Elettra, Trieste, Italy), the proposed experimental setup can be readily translated to compact laboratory systems including conventional x-ray tubes.


Assuntos
Compostos de Cádmio , Iodo , Pontos Quânticos , Camundongos , Animais , Iluminação , Fótons , Telúrio , Tomografia Computadorizada por Raios X/métodos , Imagens de Fantasmas
8.
Mikrochim Acta ; 191(4): 216, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517549

RESUMO

A photoelectrochemical (PEC) sensor for the sensitive detection of thrombin (TB) was established. Co-sensitized combination of TiO2 nanoparticles combined with modified cadmium sulfide and cadmium telluride quantum dots (CdS/CdTe QDs) was utilized as a photoactive material. Successful growth of CdS/CdTe quantum dots on mesoporous TiO2 films occured by successive ion-layer adsorption and reaction. This interesting formation of co-sensitive structure is conducive to enhancing the photocurrent response by improving the use rate of light energy. Additionally, the step-level structure of CdS/CdTe QDs and TiO2 NPs shows a wide range of visible light absorption, facilitating the dissociation of excitons into free electrons and holes. Consequently, the photoelectric response of the PEC analysis platform is significantly enhanced. This constructed PEC aptasensor shows good detection of thrombin with a low detection limit (0.033 pM) and a wide linear range (0.0001-100 nM) in diluted actual human serum samples. In addition, this PEC aptasensor also has the characteristics of good stability and good reproducibility, which provides a novel insight for the quantitative measurement of other similar analytes.


Assuntos
Compostos de Cádmio , Nanopartículas , Pontos Quânticos , Humanos , Pontos Quânticos/química , Compostos de Cádmio/química , Telúrio/química , Trombina , Reprodutibilidade dos Testes , Técnicas Eletroquímicas , Nanopartículas/química
9.
ACS Appl Mater Interfaces ; 16(12): 14510-14519, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38488618

RESUMO

Interferon-γ (IFN-γ) release assays (IGRAs) are constrained by the limited diagnostic performance of a single indicator and the excessive Mycobacterium tuberculosis (Mtb) antigen stimulation time. This study presents a simultaneous, homogeneous, rapid, and ultrasensitive fluorescence quantification strategy for IFN-γ and IFN-γ-induced protein 10 (IP-10). This method relies on the high-affinity binding of aptamers to IFN-γ and IP-10, the enzyme-free catalytic hairpin assembly reaction, and the heightened sensitivity of CdTe quantum dots to Ag+ and hairpin structure C-Ag+-C and carbon dots to Hg2+ and hairpin structure T-Hg2+-T. Under optimized conditions, the selectivity of IFN-γ and IP-10 was excellent, with a linear range spanning from 1 to 100 ag/mL and low limits of detection of 0.3 and 0.5 ag/mL, respectively. Clinical practicality was confirmed through testing of 57 clinical samples. The dual-indicator combination detection showed 92.8% specificity and 93.1% sensitivity, with an area under the curve of 0.899, representing an improvement over the single-indicator approach. The Mtb antigen stimulation time was reduced to 8 h for 6/7 clinical samples. These findings underscore the potential of our approach to enhance the efficiency and performance of a tuberculosis (TB) clinical diagnosis.


Assuntos
Compostos de Cádmio , Mercúrio , Mycobacterium tuberculosis , Ácidos Nucleicos , Pontos Quânticos , Tuberculose , Humanos , Quimiocina CXCL10 , Ensaio de Imunoadsorção Enzimática/métodos , Telúrio , Tuberculose/diagnóstico , Interferon gama/metabolismo , Antígenos
10.
Chemosphere ; 355: 141790, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554870

RESUMO

Cadmium sulfide-tin sulfide (CdS-SnS) nanoparticles are a novel kind of photocatalyst. These CdS-SnS nanoparticles are synthesized and characterized using UV-Vis, FT-IR, XRD, SEM-EDX, and DLS techniques, to understand their size distribution, crystalline nature, morphology, shape, optical properties, and elemental composition. This research offers insight into the efficient photocatalytic degradation of Phenanthrene (PHE) using CdS-SnS. The CdS-SnS NPs as photocatalyst can effectively photodegrade the polycyclic aromatic hydrocarbons (PAH) such as phenanthrene under simulated solar and UV light. UV-vis spectra of these nanoparticles exhibit peaks at 365 and 546 cm-1 respectively, the mean size of the CdS-SnS NPs in DLS is determined to be 78 nm. The CdS-SnS stretching frequency was observed at wave numbers below 700 cm-1, the absorption peak at 1123 cm-1 indicates the presence of C-N stretch or CS bond of thiourea, while the peak at 1350.38 cm-1 corresponds to the tris-amine C-N stretch in FT-IR. Additionally, the peaks observed at 2026 cm-1 indicate the presence of isothiocyanate (NCS). 1456.23 cm-1 represents the asymmetric scissor deformation vibration. EDAX revealed the presence of elemental Cd and Sn oxides. The antimicrobial studies showed that the CdS-SnS NPs at the concentration of 150 µg/mL, exhibit maximum inhibition (15 ± 1.25 mm) against the strains Proteus mirabilis followed by Staphylococcus epidermidis and Clostridium spp. Among fungal strains Colletotrichum spp. exhibits the maximum zone of inhibition (9 ± 0.25). This research also observed the cytotoxic effects of CdS-SnS NPs on HepG2 and ZF4 cells. HepG2 cells exhibited 50% inhibition at 50 µg/mL and 70% inhibition at 100 µg/mL concentrations, while ZF4 cells exhibited 50% inhibition at 50 µg/mL and 78% inhibition at 100 µg/mL concentrations, respectively. The parameters like concentration of PHE, concentration of CdS-SnS NPs, pH, and sources of irradiation on batch adsorption were examined to maximize the efficiency of the photodegradation process.


Assuntos
Compostos de Cádmio , Nanopartículas , Fenantrenos , Sulfetos , Luz , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas/química , Fenantrenos/toxicidade
11.
Asian Pac J Cancer Prev ; 25(3): 747-756, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38546057

RESUMO

QDs are semiconductor nanocrystalline materials with distinct optical and electronic characteristics due to their microscopic size and quantum mechanical properties. They are often composed of materials such as cadmium selenide (CdSe), cadmium telluride (CdTe), or indium phosphide (InP) and are typically in the size range of 2 to 10 nanometers in diameter. These tiny particles are used in various scientific and technological applications. Some key characteristics and applications of quantum dots are size-dependent Optical Properties with tunable emission. The color of light emitted by quantum dots highly depends on their size. Smaller QDs emit blue or green light, while larger ones emit red or near-infrared light. This tunability makes them valuable in various applications, especially in molecular medicine and oncology research. Quantum dots can exhibit a high quantum yield, meaning they efficiently emit light when excited, making them excellent fluorescent probes for non-invasive imaging. This review discusses the applications of QDs and their role in biomedical research and patient care, focusing on non-invasive imaging and preventive oncology.


Assuntos
Compostos de Cádmio , Nanopartículas , Pontos Quânticos , Humanos , Pontos Quânticos/química , Compostos de Cádmio/química , Telúrio , Nanopartículas/química
12.
Food Chem ; 446: 138791, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38422638

RESUMO

Acid-sensitive CdTe quantum dots-loaded alginate hydrogel (CdTe QDs-AH) beads were designed for the visual detection of SO2 residues. As proof of concept, two types of CdTe QDs were selected as model probes and embedded in AH beads. The entire test was performed within 25 min in a modified double-layer test tube with one bead fixed above the sample solution. Adding citric acid and heating at 70 ℃ for 20 min transformed the sulfites in the solution into SO2 gas, which then quenched the fluorescence of the CdTe QDs-AH beads. Using this assay, qualitative, naked-eye detection of SO2 residues was achieved in the concentration range of 25-300 ppm, as well as precise quantification was possible based on the difference in the average fluorescence brightness of the beads before and after the reaction. Five food types were successfully analysed using this method, which is simpler and more economical than existing methods, and does not require complex pretreatment.


Assuntos
Compostos de Cádmio , Pontos Quânticos , Pontos Quânticos/química , Dióxido de Enxofre , Compostos de Cádmio/química , Hidrogéis , Telúrio/química , Espectrometria de Fluorescência/métodos
13.
Colloids Surf B Biointerfaces ; 235: 113774, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309154

RESUMO

This study presents the development of a sensitive and simple enhanced ratiometric fluorescence sensing platform in the consist of CdTe quantum dots (QDs), carbon dots (CDs), and hepatitis B core antibody labeled with horseradish peroxidase (HBcAb-HRP) for the visual analysis of H2O2 and glucose. The sulfur atoms in HBcAb-HRP have a strong affinity for Cd(II), which effectively enhances the fluorescence intensity of the CdTe QDs due to the generation of more radiative centers at the CdTe/Cd-SR complex. In the presence of H2O2, the Cd-S bonds are oxidized to form disulfide products and results in linear fluorescence quenching, while CDs maintain stable. Becasue glucose can be converted into H2O2 with the aid of glucose oxidase, this sensing platform can also be used for analyzing glucose. The detection limits for H2O2 and glucose are 2.9 µmol L-1 with RSD of 2.6% and 1.6 µmol L-1 with RSD of 2.4% respectively. In addition, under UV lamp irradiation, the orange-yellow CdTe QDs gradually quench with increasing H2O2 and glucose, while the blue CDs remain unchanged. A color change from orange-yellow to blue enables a visual semi-quantitative determination of H2O2 in commercial contact lens solution and glucose in human serum without any pretreatment. Thus, this CdTe QDs/CDs ratiometric sensing platform has significant potential for the rapid analysis of H2O2 and glucose in actual application.


Assuntos
Compostos de Cádmio , Pontos Quânticos , Humanos , Peróxido de Hidrogênio/química , Pontos Quânticos/química , Glucose/química , Carbono , Compostos de Cádmio/química , Telúrio/química , Anticorpos Anti-Hepatite B , Peroxidase do Rábano Silvestre/química , Corantes Fluorescentes/química
14.
Ann Nucl Med ; 38(5): 350-359, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38347280

RESUMO

PURPOSE: Radiolabeled graphene oxide (GO) nanosheets has been one of the most extensively studied nanoplatform for in vivo radioisotope delivery. Herein, we describe the functionalization of the surface of GO nanosheets with Fe3O4 magnetic nanoparticles, cysteine amino acid as an interface ligand, and cadmium telluride quantum dots. MATERIALS AND METHODS: To enable In vivo PET imaging, the GO@Fe3O4-cys-CdTe QDs were labeled with 68Ga to yield [68Ga] Ga-Go@ Fe3O4-Cys-CdTe QDs. Furthermore, serum stability tests were performed and the biological behavior of the nanocomposite was evaluated in rats bearing fibrosarcoma tumor. RESULTS: Liver, blood and tumor were the most accumulated sites at 1 h after the injection, and the radiolabeled nanocomposite as a PET/MRI imaging agent showed fast depletion from body and acceptable tumor uptake. CONCLUSION: Magnetic (Fe3O4) and fluorescent components (CdTe QDs) along with a positron-emitting radionuclide will help to design a multimodal imaging system (PET/MRI/OI) which will offer the advantages of combined imaging techniques and further possible used in localized radionuclide therapy. Overall, [68Ga] Ga-GO@Fe3O4-cys-CdTe QDs nanocomposite shows great promise as a radiolabeled imaging agent owing to high accumulation in tumor region.


Assuntos
Compostos de Cádmio , Fibrossarcoma , Grafite , Pontos Quânticos , Ratos , Animais , Compostos de Cádmio/química , Distribuição Tecidual , Radioisótopos de Gálio/química , Pontos Quânticos/química , Telúrio/química , Tomografia por Emissão de Pósitrons , Radioisótopos , Fibrossarcoma/diagnóstico por imagem , Imagem Multimodal , Imageamento por Ressonância Magnética
15.
Food Chem ; 445: 138668, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38367555

RESUMO

Zilpaterol hydrochloride (zilpaterol) is used in animal feed as it can increase the lean meat mass. However, consuming zilpaterol-containing animal products may damage human health. Therefore, rapid detection of zilpaterol is attracting increasing research attention. This study aimed to developed a fast, accurate, and ultrasensitive fluorescence immunoassay based on CdTe quantum dots (QDs). A CdTe QD fluorescence sensor was synthesized from thioglycolic acid using a simple hydrothermal method. The morphology and structure of the CdTe QDs were characterized using transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier-transform infrared spectroscopy. The detection limits of our method in swine urine and pork samples were 0.5 µg/L and 1.2 µg/kg, respectively. A wide linear range of 0.1-10000 µg/L (R2 = 0.996) was achieved. Both within-run precision (CVw) and between-run precision (CVb) were ≤ 10 %. The method was then successfully applied for the analysis of zilpaterol contents in swine urine and pork samples.


Assuntos
Compostos de Cádmio , Carne de Porco , Pontos Quânticos , Carne Vermelha , Compostos de Trimetilsilil , Animais , Humanos , Suínos , Corantes Fluorescentes/química , Pontos Quânticos/química , Água , Compostos de Cádmio/química , Telúrio/química , Espectrometria de Fluorescência/métodos
16.
Microb Pathog ; 189: 106602, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38408546

RESUMO

The current research was designed to investigate the antibacterial activity of probiotic bacteria mediated cadmium oxide nanoparticles (CdO NPs) on common fish pathogenic bacteria like Serratia marcescens, Aeromonas hydrophila, Vibrio harveyi, and V. parahaemolyticus. CdO NPs were synthesized using probiotic bacteria as follows: Lactobacillus species with different precursor of cadmium sulfate concentrations (5, 10, and 20 mM). The average crystalline sizes of the CdO NPs were determined based on the XRD patterns using the Debye-Scherrer equation for different precursor concentrations. Specifically, sizes of 40, 48, and 67 nm were found at concentrations of 5, 10, and 20 mM, respectively. The antibacterial efficacy of CdO NPs was estimated using a well diffusion assay, which demonstrated the best efficacy of 20 mM CdO NPs against all pathogens. AFM analysis of nanoparticle-treated and untreated biofilms was performed to further validate the antibacterial effect. Antibacterial activity of CdO nanoparticles synthesized at varying concentrations (5, 10, and 20 mM) against fish pathogens (S. marcescens, A. hydrophila, V. harveyi, and V. parahaemolyticus). The results indicated the highest inhibitory effect of 20 mM CdO NPs across all concentrations (30, 60, and 90 µg/mL), demonstrating significant inhibition against S. marcescens. These findings will contribute to the development of novel strategies for combating aquatic diseases and advancing aquaculture health management practices.


Assuntos
Compostos de Cádmio , Nanopartículas Metálicas , Nanopartículas , Animais , Óxidos/química , Nanopartículas/química , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias , Peixes , Nanopartículas Metálicas/química
17.
J Nanobiotechnology ; 22(1): 78, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38414055

RESUMO

BACKGROUND: Bacterial biosynthesis of fluorescent nanoparticles or quantum dots (QDs) has emerged as a unique mechanism for heavy metal tolerance. However, the physiological pathways governing the removal of QDs from bacterial cells remains elusive. This study investigates the role of minicells, previously identified as a means of eliminating damaged proteins and enhancing bacterial resistance to stress. Building on our prior work, which unveiled the formation of minicells during cadmium QDs biosynthesis in Escherichia coli, we hypothesize that minicells serve as a mechanism for the accumulation and detoxification of QDs in bacterial cells. RESULTS: Intracellular biosynthesis of CdS QDs was performed in E. coli mutants ΔminC and ΔminCDE, known for their minicell-producing capabilities. Fluorescence microscopy analysis demonstrated that the generated minicells exhibited fluorescence emission, indicative of QD loading. Transmission electron microscopy (TEM) confirmed the presence of nanoparticles in minicells, while energy dispersive spectroscopy (EDS) revealed the coexistence of cadmium and sulfur. Cadmium quantification through flame atomic absorption spectrometry (FAAS) demonstrated that minicells accumulated a higher cadmium content compared to rod cells. Moreover, fluorescence intensity analysis suggested that minicells accumulated a greater quantity of fluorescent nanoparticles, underscoring their efficacy in QD removal. Biosynthesis dynamics in minicell-producing strains indicated that biosynthesized QDs maintained high fluorescence intensity even during prolonged biosynthesis times, suggesting continuous QD clearance in minicells. CONCLUSIONS: These findings support a model wherein E. coli utilizes minicells for the accumulation and removal of nanoparticles, highlighting their physiological role in eliminating harmful elements and maintaining cellular fitness. Additionally, this biosynthesis system presents an opportunity for generating minicell-coated nanoparticles with enhanced biocompatibility for diverse applications.


Assuntos
Compostos de Cádmio , Nanopartículas , Pontos Quânticos , Sulfetos , Escherichia coli/metabolismo , Cádmio , Nanopartículas/química , Pontos Quânticos/química , Corantes/metabolismo
18.
J Inorg Biochem ; 253: 112484, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38219407

RESUMO

The light-driven reduction of dinitrogen (N2) to ammonia (NH3) catalyzed by a cadmium sulfide (CdS) nanocrystal­nitrogenase MoFe protein biohybrid is dependent on a range of different factors, including an appropriate hole-scavenging sacrificial electron donor (SED). Here, the impact of different SEDs on the overall rate of N2 reduction catalyzed by a CdS quantum dot (QD)-MoFe protein system was determined. The selection of SED was guided by several goals: (i) molecules with standard reduction potentials sufficient to reduce the oxidized CdS QD, (ii) molecules that do not absorb the excitation wavelength of the CdS QD, and (iii) molecules that could be readily reduced by sustainable processes. Earlier studies utilized buffer molecules or ascorbic acid as the SED. The effectiveness of ascorbic acid as SED was compared to dithionite (DT), triethanolamine (TEOA), and hydroquinone (HQ) across a range of concentrations in supporting N2 reduction to NH3 in a CdS QD-MoFe protein photocatalytic system. It was found that TEOA supported N2 reduction rates comparable to those observed for dithionite and ascorbic acid. HQ was found to support significantly higher rates of N2 reduction compared to the other SEDs at a concentration of 50 mM. A comparison of the rates of N2 reduction by the biohybrid complex to the standard reduction potential (Eo) of the SEDs reveals that Eo is not the only factor impacting the efficiency of hole-scavenging. These findings reveal the importance of the SED properties for improving the efficiency of hole-scavenging in the light-driven N2 reduction reaction catalyzed by a CdS QD-MoFe protein hybrid.


Assuntos
Azotobacter vinelandii , Compostos de Cádmio , Nitrogenase , Sulfetos , Nitrogenase/metabolismo , Molibdoferredoxina/metabolismo , Oxirredução , Ditionita/metabolismo , Catálise , Ácido Ascórbico/metabolismo , Azotobacter vinelandii/metabolismo
19.
Food Chem ; 442: 138458, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38278103

RESUMO

Malachite green (MG) possesses high toxicity, therefore, the detection of MG in fish tissues is of vital importance. A novel core-shell MIPs doped CdTe quantum dots coated silica nanoparticles (CdTe-MIP/SiO2 NPs) were synthesized via a simple one-pot strategy. The materials were characterized carefully. The resulting CdTe-MIP/SiO2 NPs were coated on the thin layer chromatography plate, and coupled with miniaturized fluorimeter for fluorescence detection of MG in fish samples. The resulting CdTe-MIP/SiO2 NPs based system possessed good linearity (0.01 âˆ¼ 20 µmol/L), high recoveries (98.36 %∼101.45 %) and low detection limit (3.7 nmol/L) for MG. Furthermore, CdTe-MIP/SiO2 NPs based system were employed to measure fish samples spiked with MG, meanwhile, HPLC was utilized to evaluate the accuracy and reliability. And the paired t-test was conducted to evaluate differences between fluorescence method and HPLC, P > 0.05 means no significant difference was observed, the results demonstrated that both fluorescence method and HPLC are suitable for MG analysis.


Assuntos
Compostos de Cádmio , Impressão Molecular , Pontos Quânticos , Corantes de Rosanilina , Animais , Polímeros Molecularmente Impressos , Pontos Quânticos/química , Compostos de Cádmio/química , Dióxido de Silício/química , Reprodutibilidade dos Testes , Telúrio/química , Impressão Molecular/métodos , Peixes , Limite de Detecção
20.
Food Chem ; 441: 138350, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38183725

RESUMO

Based on the fluorescence sensor of 3-Mercaptopropionic acid (MPA) capped CdTe quantum dots (QDs), two novel detection methods for aklomide and nitromide were developed. The MPA-CdTe QDs were synthesized and characterized by transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), ultraviolet visible (UV-vis) and fluorescence (FL). The quenchings were all static. The binding constants (Ka) at different temperatures were obtained. Electrostatic forces were the main forces for the two bindings. For the detection of aklomide and nitromide, under the optimal conditions, the effects of some metal ions, glucose, bovine serum albumin (BSA) and congeneric drug on the determination were explored. The standard equations were established and the limits of detection (LOD) were 0.0215 and 0.0388 µg mL-1 (3S0/S), repectively. The methods were applied to analyse the samples of chicken and duck, the recoveries were 99.41 % - 101.24 % with RSDs of 0.29 % - 1.19 % (n = 5).


Assuntos
Benzamidas , Compostos de Cádmio , Pontos Quânticos , Pontos Quânticos/química , Compostos de Cádmio/química , Fluorescência , Telúrio/química , Espectrometria de Fluorescência
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