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1.
J Colloid Interface Sci ; 678(Pt B): 938-945, 2025 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-39270393

RESUMO

Water contamination owing to anionic pollutants is a persisting and ubiquitous global threat. The current remediation technologies are mostly low in efficiency, expensive in materials and often associated with complicated processes. Herein, we report a characteristic zirconium-based nanocluster that can work as molecular robots for the efficient remediation of anions-contaminated water with great effectiveness and molecular-level accuracy. It exhibits a stimuli-responsive behavior to facilitate the water treatment process: dissolve in acidic aqueous solutions for molecular-level decontamination and quickly aggregate for post-remediation collection. It can precisely capture the representative anionic pollutants, whilst featuring satisfactory capacities (ca. 175 mg-arsenic/g, 60 mg-chromium/g, 45 mg-fluoride/g, 70 mg-phosphorus/g, respectively), super-fast kinetics (finishing uptake within seconds, which is two to four orders of magnitude faster than typical sorbents), as well as multi-cycle applications without appreciable loss of activity. The coexisting common ions show no effect on the target uptake. The responsible active site investigation shows that four active sites are responsible for the monovalent pollutant removal, and the active sites work in pairs to capture divalent chromate species. Cost analysis shows its economical applicability in practical applications. This work would lead to the development of effective water decontamination with higher effectiveness, more convenience, lower cost and more practical application value.

2.
Front Nucl Med ; 4: 1426650, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39355210

RESUMO

Introduction: Nuclear medicine infection imaging is routinely performed with the use of leukocytes radiolabelled with technetium-99m hexamethylpropyleneamine oxime ([99mTc]Tc-HMPAO) and single-photon emission computed tomography (SPECT). Positron emission tomography (PET) is more sensitive than SPECT and results in higher-quality images. Zirconium-89 (89Zr) is a positron emitter with a half-life of 78.4 h, which translates to the biological half-life and slow biodistribution of intact cells and allows delayed PET imaging for more accurate biodistribution of the labelled leukocytes to infection foci. A first-in-human study with [89Zr]Zr-oxine-leukocytes in four healthy volunteers was reported in 2022. Our first-in-human study utilising the cell surface labelling approach aimed to image infection in patients with the use of 89Zr-labelled leukocytes, using p-isothiocyanatobenzyl-desferrioxamine B (Df-Bz-NCS) as a bifunctional chelating agent, and to compare the scan quality and biodistribution of [89Zr]Zr-Df-Bz-NCS-labelled leukocytes on PET images to SPECT images obtained with [99mTc]Tc-HMPAO-labelled leukocytes. Methods: Leukocytes were isolated from whole-blood samples of eight patients with clinically and/or radiologically confirmed infection. Isolated leukocytes were labelled with [99mTc]Tc-HMPAO according to standardised methods, and [89Zr]Zr-Df-Bz-NCS according to our previously published radiolabelling method. Whole-body SPECT imaging was performed 2 and 18 h post injection of [99mTc]Tc-HMPAO-labelled leukocytes, and whole-body PET/CT was performed 3 and 24 h post injection of [89Zr]Zr-Df-Bz-NCS-labelled leukocytes in seven patients. Results: Successful [89Zr]Zr-Df-Bz-NCS-leukocyte labelling was achieved. High labelling efficiencies were obtained (81.7% ± 3.6%; n = 8). A mean high viability of [89Zr]Zr-Df-Bz-NCS-labelled leukocytes was observed (88.98% ± 12.51%). The [89Zr]Zr-Df-Bz-NCS-leukocyte labelling efficiency was not significantly affected by the white blood cell count of the patient. The performance of [99mTc]Tc-HMPAO- and [89Zr]Zr-Df-Bz-NCS-labelled leukocytes, in terms of the ability to accurately detect infection, were similar in two out of seven patients, and [99mTc]Tc-HMPAO-labelled leukocytes outperformed [89Zr]Zr-Df-Bz-NCS-labelled leukocytes in one patient with femoral osteomyelitis. However, in two cases of pulmonary pathology, [89Zr]Zr-Df-Bz-NCS-labelled leukocytes demonstrated improved pathological uptake. No skeletal activity was observed in any of the patients imaged with [89Zr]Zr-Df-Bz-NCS-labelled leukocytes, illustrating the in vivo stability of the radiolabel. Discussion: Although the [89Zr]Zr-Df-Bz-NCS-leukocyte labelling aspect of this study was noteworthy, infection imaging did not yield convincingly positive results due to the pulmonary trapping of intravenously administered [89Zr]Zr-Df-Bz-NCS-labelled leukocytes.

3.
Cancer Imaging ; 24(1): 132, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39375762

RESUMO

BACKGROUND: Positron emission tomography/computed tomography (PET/CT) using prostate-specific membrane antigen (PSMA)-targeted radiotracers labeled with zirconium-89 (89Zr; half-life ~ 78.41 h) showed promise in localizing biochemical recurrence of prostate cancer (BCR) in pilot studies. METHODS: Retrospective analysis of 38 consecutive men with BCR (median [minimum-maximum] prostate-specific antigen 0.52 (0.12-2.50 ng/mL) undergoing [89Zr]Zr-PSMA-617 PET/CT post-negative [68Ga]Ga-PSMA-11 PET/CT. PET/CT acquisition 1-h, 24-h, and 48-h post-injection of a median (minimum-maximum) [89Zr]Zr-PSMA-617 tracer activity of 123 (84-166) MBq. RESULTS: [89Zr]Zr-PSMA-617 PET/CT detected altogether 57 lesions: 18 local recurrences, 33 lymph node metastases, 6 bone metastases in 30/38 men with BCR (78%) and prior negative conventional PSMA PET/CT. Lesion uptake significantly increased from 1-h to 24-h and, in a majority of cases, from 24-h to 48-h. Tumor-to-background ratios significantly increased over time, with absolute increases of 100 or more. No side effects were noted. After [89Zr]Zr-PSMA-617 PET/CT-based treatment, prostate-specific antigen concentration decreased in all patients, becoming undetectable in a third of patients. LIMITATIONS: retrospective, single center design; infrequent histopathological and imaging verification. CONCLUSION: This large series provides further evidence that [89Zr]Zr-PSMA-617 PET/CT is a beneficial imaging modality to localize early BCR. A remarkable increase in tumor-to-background ratio over time allows localization of tumor unidentified on conventional PSMA PET/CT.


Assuntos
Dipeptídeos , Recidiva Local de Neoplasia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Antígeno Prostático Específico , Neoplasias da Próstata , Zircônio , Humanos , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Antígeno Prostático Específico/sangue , Radioisótopos , Compostos Radiofarmacêuticos , Compostos Heterocíclicos com 1 Anel , Idoso de 80 Anos ou mais
4.
Artigo em Inglês | MEDLINE | ID: mdl-39445472

RESUMO

As electronic circuit integration intensifies, there is a rising demand for dielectric insulators that provide both superior insulation and high dielectric constants. This study focuses on developing high-k dielectric insulators by controlling the phase of the Hf0.5Zr0.5O2 (HZO) film with additional doping, utilizing yttrium (Y), tantalum (Ta), gallium (Ga), silicon (Si), and aluminum (Al) as dopants. Doping changes the ratio of tetragonal to monoclinic phases in doped HZO films, and Y-doped HZO (Y:HZO) films specifically exhibit a high tetragonal phase ratio and a dielectric constant of 40.9, indicating superior insulating properties compared to undoped HZO films. To clarify the fundamental mechanism driving the enhancement in dielectric properties, we have carried out various analyses combined with density functional theory (DFT) calculations. Through the optimization of the post-deposition annealing (PDA) process and the heterojunction structure with Al2O3, an Al2O3/Y:HZO heterojunction with a high dielectric constant and even lower leakage current compared to a single layer was developed. The thin-film transistor (TFT) with the Au/Ti/amorphous InGaZnO4 (a-IGZO)/Al2O3/YHZO/TiN heterojunction structure exhibits low subthreshold swing (SS) values within a narrow gate-source voltage (Vsg) range. This study advances knowledge on how the controlled-phase doped HZO films affect the dielectric constant and leakage current and will contribute to semiconductor technology advancements by overcoming the limitations of conventional high-k dielectric insulators.

5.
Int J Nanomedicine ; 19: 10387-10400, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39430310

RESUMO

Background: Age-related macular degeneration (AMD) is becoming the leading cause of blindness in the aged population. The death of photoreceptors is the principal event which is lack of curative treatment. Xaliproden, a highly selective synthetic 5-OH-tryptamine (5HT) 1A receptor agonist, has the neuroprotective potential. However, its application has been limited by the insoluble formulation, low utilization efficiency and side effects caused by systemic administration. Methods: Nanoscale zirconium-porphyrin metal-organic framework (NPMOF) was used as a skeleton and loaded with xaliproden (XAL) to prepare a novel kind of nanoparticle, namely, XAL-NPMOF. The human umbilical vein endothelial cells, zebrafish embryos and larvae were used to test the biotoxicity and fluorescence imaging capability of XAL-NPMOF both in vitro and in vivo. A photoreceptor degeneration model was generated by intense light injury in adult zebrafish and XAL-NPMOF was delivered to the injured retina by intraocular injection. The photoreceptor regeneration, inflammatory response and visual function were explored by immunohistochemistry, quantitative real-time polymerase chain reaction and optomotor response analysis. Results: Following a single XAL-NPMOF intraocular injection, the injured retina underwent the faster photoreceptor regeneration with a recovery of visual function via promoting cell proliferation, suppressing the inflammatory responses and increasing the expression of antioxidases. Conclusion: As an amplifier, NPMOF can enhance the anti-inflammatory efficacy and neuroprotective effect of xaliproden. XAL-NPMOF could be a novel and convenient option for the treatment of AMD.


Assuntos
Células Endoteliais da Veia Umbilical Humana , Estruturas Metalorgânicas , Porfirinas , Regeneração , Peixe-Zebra , Zircônio , Animais , Zircônio/química , Zircônio/farmacologia , Humanos , Porfirinas/química , Porfirinas/farmacologia , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Degeneração Macular/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Nanopartículas/química , Inflamação/tratamento farmacológico , Células Fotorreceptoras de Vertebrados/efeitos dos fármacos
6.
Gels ; 10(10)2024 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-39451309

RESUMO

The sol-gel process is a green method used in the last few decades to synthesize new organic-inorganic phosphorus-containing hybrid materials. The sol-gel synthesis is a green method because it takes place in mild conditions, mostly by using water or alcohol as solvents, at room temperature. Therefore, the sol-gel method is, among others, a promising route for obtaining metal-phosphonate networks. In addition to phosphorus, the obtained hybrid materials could also contain titanium, zirconium, boron, and other elements, which influence their properties. The sol-gel process has two steps: first, the sol formation, and second, the transition to the gel phase. In other words, the sol-gel process converts the precursors into a colloidal solution (sol), followed by obtaining a network (gel). By using the sol-gel method, different organic moieties could be introduced into an inorganic matrix, resulting in organic-inorganic hybrid structures (sometimes they are also referred as organic-inorganic copolymers).

7.
Int J Biol Macromol ; : 136830, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39461635

RESUMO

The increasing presence of uranium as a radionuclide contaminant in water is a threat to human health and the environment. Sonication-assisted crosslinking of guar gum, a biopolymer, is carried out with zirconium phosphate to form an adsorbent (GG@ZrP) for the removal of uranium from water. The surface characteristics, functionalities, and thermal stability of the composite were established using various analytical and spectral tools. Langmuir, Freundlich, and Sips models were used to evaluate the batch adsorption parameters. The adsorbent exhibited an excellent Langmuir adsorption capacity of 500 mg g-1 towards adsorption of uranium at pH 6. The adsorption was endothermic (ΔH, 22.63 kJ mol-1) and followed pseudo-second order kinetics. The synergistic influence of hydroxyl-rich guar gum and phosphate moieties resulted in efficient binding of uranium. With a high selectivity towards interfering cations and anions and applicability over a good range of pH, this adsorbent is a promising candidate for uranium remediation from water.

9.
Artigo em Inglês | MEDLINE | ID: mdl-39422864

RESUMO

New anodes consisting of zirconium-doped PbO2 coating, growth on titanium dioxide interlayer, were deposited on titanium substrates using spin coating method and have been tested for the removal of ampicillin, a ß-lactam antibiotic, from water. Morphological, structural, and electrochemical properties of the prepared coatings were characterized by scanning electron microscopy (SEM), atomic force microscope (AFM), X-ray diffraction (XRD), and electrochemical impendence spectroscopy (EIS). Results showed that the incorporation of zirconium dopant had a noticeable modification in the morphology of anodes. An increase in the surface roughness and the specific active area were observed with Ti/TiO2/PbO2- 10% Zr electrode compared to other anodes. The electrochemical measurements indicated that the anode doped with 10% Zr showed a more protective coating performance than the undoped and 20% Zr-doped PbO2 electrodes. The experiments on ampicillin degradation revealed that doped lead dioxide anodes have excellent electrocatalytic activity. The major byproduct generated during anodic oxidation treatment has been identified as ampicilloic acid by liquid chromatography-mass spectroscopy (LC-MS) analysis. Results demonstrated that Ti/TiO2/PbO2- 10% Zr anode presents the best removal rate of ampicillin with a minimum intermediate amount, which leads to conclude that 10% is the optimum percentage of zirconium dopant for antibiotic wastewater treatment.

10.
Front Nucl Med ; 4: 1360710, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39355220

RESUMO

Immuno-positron emission tomography (immunoPET) enables imaging of specific targets that play a role in targeted therapy and immunotherapy, such as antigens on cell membranes, targets in the disease microenvironment, or immune cells. The most common immunoPET applications use a monoclonal antibody labeled with a relatively long-lived positron emitter such as 89Zr (T 1/2 = 78.4 h), but smaller antibody-based constructs labeled with various other positron emitting radionuclides are also being investigated. This molecular imaging technique can thus guide the development of new drugs and may have a pivotal role in selecting patients for a particular therapy. In early phase immunoPET trials, multiple imaging time points are used to examine the time-dependent biodistribution and to determine the optimal imaging time point, which may be several days after tracer injection due to the slow kinetics of larger molecules. Once this has been established, usually only one static scan is performed and semi-quantitative values are reported. However, total PET uptake of a tracer is the sum of specific and nonspecific uptake. In addition, uptake may be affected by other factors such as perfusion, pre-/co-administration of the unlabeled molecule, and the treatment schedule. This article reviews imaging methodologies used in immunoPET studies and is divided into two parts. The first part summarizes the vast majority of clinical immunoPET studies applying semi-quantitative methodologies. The second part focuses on a handful of studies applying pharmacokinetic models and includes preclinical and simulation studies. Finally, the potential and challenges of immunoPET quantification methodologies are discussed within the context of the recent technological advancements provided by long axial field of view PET/CT scanners.

11.
Drug Dev Res ; 85(7): e22266, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39363532

RESUMO

This study presents the development and evaluation of a DFO@mAb-NP (DFO@Durvalumab-HSA-DTX nanoparticle) nanoplatform for imaging in triple-negative breast cancer (TNBC). The nanoplatform demonstrated significant changes postconjugation with DFO, evidenced by increased particle size from 178.1 ± 5 nm to 311 ± 26 nm and zeta potential alteration from -31.9 ± 3 mV to -40.5 ± 0.8 mV. Fourier-transform infrared spectroscopy and ultraviolet spectral analyses confirmed successful DFO conjugation, with notable shifts in peak wavelengths. High labeling efficiency was achieved with 89Zr, as indicated by thin layer radio chromatography and high-performance liquid radio chromatography results, with labeling efficiencies of 98 ± 2% for 89Zr-DFO@mAb and 96 ± 3% for 89Zr-DFO@mAb-NP. The nanoplatforms maintained stability over 24 h, showing less than 5% degradation. Lipophilicity assays revealed logP values of 0.5 ± 0.03 for 89Zr-DFO@mAb-NP and 0.98 ± 0.2 for 89Zr-DFO@mAb, indicating a higher lipophilic tendency in the radiolabeled Durvalumab. Cell uptake experiments showed an initial high uptake in MDA-MB-468 cells (45.1 ± 3.2%), which decreased over time, highlighting receptor-specific interactions. These comprehensive findings suggest the promising potential of the DFO@mAb-NP nanoplatform for targeted imaging in TNBC, with implications for improved diagnostic accuracy and treatment strategies.


Assuntos
Nanopartículas , Radioisótopos , Neoplasias de Mama Triplo Negativas , Zircônio , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Humanos , Nanopartículas/química , Zircônio/química , Radioisótopos/química , Linhagem Celular Tumoral , Desferroxamina/química , Desferroxamina/farmacologia , Feminino
12.
Artigo em Inglês | MEDLINE | ID: mdl-39386127

RESUMO

Background: An esthetically acceptable ceramic restoration should have optical properties like the teeth and reflect, transmit, and absorb light. The present investigation compared how hydrothermal aging affected the properties of two types of zirconia and lithium disilicate. Methods: Thirty rectangular samples (12×14×1 mm) were prepared and sectioned from three different ceramic blocks/blanks (n=10), then assigned into three groups according to the ceramic type: group Z: IPS e.max ZirCAD prime, gradient zirconia (3Y/5Y-TZP); group K: Katana UTML (5Y-TZP); and group E: IPS e.max CAD (lithium disilicate). Color analysis of samples was performed before and after hydrothermal aging (1, 3, and 5 hours) using a spectrophotometer. Color difference (∆E00), translucency parameter (TP00), and contrast ratio (CR) were evaluated. The microstructural analysis was performed using x-ray diffraction (XRD). Data were statistically analyzed at a significance level of P<0.05. Results: A statistically significant variation was observed across means of ∆E00, TP00, and CR at different times. Group Z displayed the highest statistically significant mean ∆E00. Group E demonstrated the greatest statistically significant mean TP00. Group K exhibited the most statistically significant mean CR. Conclusion: Hydrothermal aging significantly affected the optical characteristics of lithium disilicate and zirconia ceramics. The translucency of samples increased with aging.

13.
Front Dent ; 21: 32, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39403236

RESUMO

Objectives: We aimed to evaluate ceramic-alloy interface and emphasize the alteration of alloy microstructure after ceramic layering. Materials and Methods: Thirty-two discs made from a ceramic-alloy combination of pre-sintered cobalt-chromium (CoCr), cast CoCr, cast nickel-chromium (NiCr), or pre-sintered zirconia were prepared with eight discs in each group. Four specimens were examined as manufactured and four were ceramic-layered. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-Ray diffractometer (XRD), and an atomic force microscope were used for analysis. Non-layered specimens received ceramic fire-heating without adding any ceramic. Alloy microstructure was compared before and after ceramic veneering or heating within the same group. Mean differences in grain size and surface roughness were compared among groups. P<0.05 was considered significant. Results: SEM showed a close bonding interface between alloys and ceramics. EDX demonstrated differences compared to the manufacturer's composition. Ceramic-layering reduced grain size for both milled alloys (P<0.05), whereas grain size increased in cast groups (P=0.011). Heat treatment did the same for the CoCr groups (P=0.013). Ceramic veneering increased the surface roughness of the cast CoCr (Gi) (P=0.029) and NiCr (Wi) (P=0.005) groups, whereas zirconia roughness average (Ra) showed a slight decrease (P=0.282). XRD showed no differences among zirconia, NiCr, and milled CoCr groups before and after veneering. Crystallite size differed between monoclinic and tetragonal phases in zirconia. Conclusion: The study highlights that ceramic-layering induces significant microstructural changes in alloys, enhancing bonding potential and mechanical stability. Pre-sintered materials show a fine homogeneous surface, optimizing ceramic adherence and potentially improving clinical outcomes.

14.
ChemSusChem ; : e202401800, 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39429095

RESUMO

The catalytic performance of phosphate-stabilized WOx-ZrO2 compositions in gas-phase glycerol dehydration has been investigated. Results show that varying WO3 concentrations direct the process towards either acrolein or allyl alcohol formation. Catalysts with low WOx content exhibit strong Lewis acid sites (Zr4+ and W6+), where these metal ions likely function as redox sites, facilitating glycerol hydrogenolysis to produce allyl alcohol. Higher WO3 concentrations (exceeding 20 wt.%) lead to the shielding of some W6+ and Zr4+ sites by polytungstate surface complexes, which are strong Brønsted acid sites. This alteration promotes glycerol dehydration through the removal of two water molecules, thereby shifting the selectivity towards acrolein formation.

15.
Nanomaterials (Basel) ; 14(19)2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39404294

RESUMO

The <100> oriented single-crystalline Zirconium Carbide (ZrC) nanowires were controllably synthesized on a graphite substrate by chemical vapor deposition (CVD) with optimized growth parameters involving Zirconium tetrachloride (ZrCl4), flow of methane (CH4), and growth temperature. The length of nanowires is above 10 µm while the diameter is smaller than 100 nm. A single ZrC nanowire was picked up and fixed on a tungsten tip for field emission measurement. After surface pretreatments, a sharpened and cleaned ZrC nanowire emitter showed a high emission current density of 1.1 × 1010 A m-2 at a low turn-on voltage of 440 V. The field emission is stable for 150 min with a fluctuation of 1.77%. This work provides an effective method for synthesizing and stabilizing single-crystalline ZrC nanowire emitters as an electron source for electron-beam applications.

16.
Polymers (Basel) ; 16(19)2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39408437

RESUMO

Polypropylene and ammonium phosphate (AP) composites were synthesized at a 25 wt% concentration. The changes in the morphological, thermal, and physical behavior of the composites were analyzed with the addition of lignosulfonate (LG) and zirconium phosphate (ZrP). Additionally, metallic zirconium was deposited onto lignosulfonate using the magnetron sputtering technique to develop polypropylene and zirconium-modified lignosulfonate (LGMod) composites. Thus, composites of PP/25AP, PP/25AP/8LG/5ZrP, and PP/25AP/8LGMod were synthesized. The synthesis involved mixing the materials in a Hake mixer, followed by compression molding. The composites were characterized by field emission scanning electron microscopy (SEM-EDS), a thermogravimetric analysis (TGA) with combustion parameters, a vertical burn test (UL-94), a thermal camera, and mechanical properties. All composites achieved a V2 rating according to UL-94 standards. The PP/25AP extinguishes flames more quickly compared to other materials, approximately 99.2% faster than PP and showed the lowest temperature variation and mass loss after burning. The PP/25AP/8LG/5ZrP composite exhibited a 7% higher rigidity and 84.5% better flame retardancy compared to pure PP. Additionally, substituting ZrP with LGMod led to a lower environmental impact and improved thermal properties, despite some mechanical disadvantages.

17.
Heliyon ; 10(17): e37342, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39290268

RESUMO

Copper and its alloys due to favorable properties such as ductility, high electrical and thermal conductivity are very important in various industries. The coating of rare earth elements and intermediate elements is a suitable method to form a super-hydrophobic coating on copper substrate. The aim of this research is to fabricate a controlled super-hydrophobic coating of cerium-zirconium myristate on the copper base using the electrochemical deposition process and to prevent the corrosive solution penetration and reaching to the copper substrate due to removing the corrosive solution from the surface of the coating. The variables parameters in this process are the change of deposition time, the different concentrations of cerium chloride, and zirconium chloride salts and is necessary to investigate their effect of them on the structural morphology, wettability and corrosion properties. According to the results of Field Emission Scanning Electron Microscope (FE-SEM), the surface morphology of the coatings is consisted of lotus-like nano and micro leaves. Furthermore, the wettability of the prepared coatings was analyzed and observed by measuring the contact angle of the coating with water droplet that the fabricated coating from the electrolyte containing 0.056 M of cerium chloride, 0.014 M of zirconium chloride, 0.1 M of myristic acid, 10 ml of hydrochloric acid and ethanol solvent has super-hydrophobic properties and the contact angle with water droplet is measured at 161°. The FT-IR and EDS analysis showed that the chemical composition of lotus-like leaves is cerium myristate and zirconium myristate. As a result, it can be inferred that the type of morphology and surface roughness play an important role in inducing the super-hydrophobic properties and has the most effect on the corrosion resistance of the coating due to the formation air pockets and then to prevents the corrosive solution penetration through the cross section of the coating and reaches to the copper substrate.

18.
Mol Pharm ; 21(10): 5205-5216, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39322604

RESUMO

B7-H3 has emerged as a promising target and potential biomarker for diagnosing tumors, evaluating treatment efficacy, and determining patient prognosis. Hu4G4 is a recombinant humanized antibody that selectively targets the extracellular domain of human B7-H3. In this study, we describe the radiolabeling of hu4G4 with the positron emission tomography (PET) emitter radionuclide zirconium 89 (89Zr) and evaluate its potency as an immuno-PET tracer for B7-H3-targeted imaging by comparing it in vitro and in vivo to [89Zr]Zr-DFO-DS-5573a using various models. The radiolabeled compound, [89Zr]Zr-desferrioxamine-hu4G4 ([89Zr]Zr-DFO-hu4G4), demonstrated a high radiochemical purity (RCP) of greater than 99% and a specific activity of 74 MBq/mg following purification. Additionally, it maintained stability in human serum albumin (HSA) and acetate buffer, preserving over 90% of its RCP after 7 days. Three cell lines targeting human B7-H3(U87/CT26-CD276/GL261-CD276) were used. Flow cytometry analysis indicated that the B7-H3-positive cells (U87/CT26-CD276/GL261-CD276) had a higher B7-H3 protein level with no expression in the B7-H3-negative cells (CT26-wt/GL261-wt) (P < 0.001). Moreover, the cellular uptake was 45.71 ± 3.78% for [89Zr]Zr-DFO-hu4G4 in CT26-CD276 cells versus only 0.93 ± 0.47% in CT26-wt cells and 30.26 ± 0.70% when [89Zr]Zr-DFO-hu4G4 in CT26-CD276 cells were blocked with 100× 8H9. The cellular uptake of [89Zr]Zr-DFO-hu4G4 was akin to that observed with [89Zr]Zr-DFO-DS-5573a with no significant differences (45.71 ± 3.78 % vs 47.07 ± 0.86 %) in CT26-CD276 cells. Similarly, the CT26-CD276 mouse model demonstrated markedly low organ uptake and elevated tumor uptake 48 h after [89Zr]Zr-DFO-hu4G4 injection. PET/CT analysis showed that the tumor-to-muscle (T/M) ratios were substantially higher compared to other imaging groups: 27.65 ± 3.17 in CT26-CD276 mice versus 11.68 ± 4.19 in CT26-wt mice (P < 0.001) and 16.40 ± 0.78 when 100× 8H9 was used to block [89Zr]Zr-DFO-hu4G4 in CT26-CD276 mice (P < 0.01) at 48 h post-injection. Additionally, the tracer showed markedly high accumulation in the tumor region (22.57 ± 3.03% ID/g), comparable to the uptake of [89Zr]Zr-DFO-DS-5573a (24.76 ± 5.36% ID/g). A dosimetry estimation study revealed that the effective dose for [89Zr]Zr-DFO-hu4G4 was 2.96 × 10-01 mSv/MBq, which falls within the acceptable range for further research in nuclear medicine. Collectively, these results indicated that [89Zr]Zr-DFO-hu4G4 was successfully fabricated and applied in B7-H3-targeted tumor PET/CT imaging, which showed excellent imaging quality and tumor detection efficacy in tumor-bearing mice. It is a promising imaging agent for identifying tumors that overexpress B7-H3 for future clinical applications.


Assuntos
Antígenos B7 , Tomografia por Emissão de Pósitrons , Radioisótopos , Zircônio , Zircônio/química , Animais , Humanos , Antígenos B7/metabolismo , Camundongos , Radioisótopos/química , Linhagem Celular Tumoral , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Anticorpos Monoclonais Humanizados/química , Distribuição Tecidual , Feminino , Desferroxamina/química , Neoplasias/diagnóstico por imagem , Camundongos Endogâmicos BALB C , Camundongos Nus
19.
ACS Appl Mater Interfaces ; 16(40): 53801-53810, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39340414

RESUMO

Aqueous zinc ion batteries are excellent energy storage devices with high safety and low cost. However, the corrosion reaction and zinc dendrite formation occurring on the surface of zinc anodes are hindering their further development. To solve the problems, zirconium acetate (ZA) was used as an electrolyte additive in the ZnSO4 electrolyte. Attributing to the higher electro-positivity of Zr4+ than Zn2+, these high valence metal cations preferentially adsorb onto the surface of metallic zinc, shielding parasitic reactions between zinc and electrolyte, reshaping the electric field distribution, and directing preferential homogeneous deposition of Zn-ions on the Zn (002) crystal plane. Furthermore, the adsorption of Zr4+ on the Zn metal after electrochemical cycles can enhance the energy barrier of zinc atom diffusion, resulting in high resistance of corrosion and manipulation of the Zn2+ nucleation configuration. Attributing to these properties, the Zn//Zn symmetric cell with an electrolyte additive of ZA was able to cycle for 400 h under an extremely high current density of 40 mA cm-2 with an area capacity of 2 mAh cm-2. Meanwhile, the MnO2//Zn coin cell still had 81.7 mAh g-1 (85% retention of capacity) after 850 cycles under a current density of 1 A g-1.

20.
Colloids Surf B Biointerfaces ; 245: 114237, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39293292

RESUMO

Titanium (Ti) is an ideal material for dental implants due to its excellent properties. However, corrosion and mechanical wear lead to Ti ions and particles release, triggering inflammatory responses and bone resorption. To overcome these challenges, surface modification techniques are used, including micro-arc oxidation (MAO). MAO creates adherent, porous coatings on Ti implants with diverse chemical compositions. In this context, zirconia element stands out in its wear and corrosion properties associated with low friction and chemical stability. Therefore, we investigated the impact of adding zirconium oxide (ZrO2) to Ti surfaces through MAO, aiming for improved electrochemical and mechanical properties. Additionally, the antimicrobial and modulatory potentials, cytocompatibility, and proteomic profile of surfaces were investigated. Ti discs were divided into four groups: machined - control (cpTi), treated by MAO with 0.04 M KOH - control (KOH), and two experimental groups incorporating ZrO2 at concentrations of 0.04 M and 0.08 M, composing the KOH@Zr4 and KOH@Zr8 groups. KOH@Zr8 showed higher surface porosity and roughness, even distribution of zirconia, formation of crystalline phases like ZrTiO4, and hydrophilicity. ZrO2 groups showed better mechanical performance including higher hardness values, lower wear area and mass loss, and higher friction coefficient under tribological conditions. The formation of a more compact oxide layer was observed, which favors the electrochemical stability of ZrO2 surfaces. Besides not inducing greater biofilm formation, ZrO2 surfaces reduced the load of pathogenic bacteria evidenced by the DNA-DNA checkerboard analysis. ZrO2 surfaces were cytocompatible with pre-osteoblastic cells. The saliva proteomic profile, evaluated by liquid chromatography coupled with tandem mass spectrometry, was slightly changed by zirconia, with more proteins adsorbed. KOH@Zr8 group notably absorbed proteins crucial for implant biological responses, like albumin and fibronectin. Incorporating ZrO2 improved the mechanical and electrochemical behavior of Ti surfaces, as well as modulated biofilm composition and provided suitable biological responses.

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