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1.
RSC Adv ; 14(8): 5440-5448, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38348293

RESUMEN

Lead-free halide double perovskite (LFHDP) Cs2AgBiBr6 has emerged as a promising alternative to traditional lead-based perovskites (LBPs), offering notable advantages in terms of chemical stability and non-toxicity. However, the efficiency of Cs2AgBiBr6 solar cells faces challenges due to their wide bandgap (Eg). As a viable strategy to settle this problem, we consider optimization of the optical and photovoltaic properties of Cs2AgBiBr6 by Gallium (Ga) substitution. The synthesized Cs2Ag0.95Ga0.05BiBr6 is rigorously characterized by means of X-ray diffraction (XRD), UV-vis spectroscopy, and solar simulator measurements. XRD analysis reveals shifts in peak positions, indicating changes in the crystal lattice due to Ga substitution. The optical analysis demonstrates a reduction in the Eg, leading to improvement of the light absorption within the visible spectrum. Importantly, the Cs2Ag0.95Ga0.05BiBr6 solar cell exhibits enhanced performance, as evidenced by higher values of open circuit voltage (Voc), short-circuit current (Jsc), and fill factor (FF), which are 0.94 V, 6.01 mA cm-2, and 0.80, respectively: this results in an increased power conversion efficiency (PCE) from 3.51% to 4.52%. This research not only helps to overcome film formation challenges, but also enables stable Cs2Ag0.95Ga0.05BiBr6 to be established as a high-performance material for photovoltaic applications. Overall, our development contributes to the advancement of environmentally friendly solar technologies.

2.
Int J Nanomedicine ; 19: 5813-5835, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38895143

RESUMEN

Breast and ovarian cancers, despite having chemotherapy and surgical treatment, still have the lowest survival rate. Experimental stages using nanoenzymes/nanozymes for ovarian cancer diagnosis and treatment are being carried out, and correspondingly the current treatment approaches to treat breast cancer have a lot of adverse side effects, which is the reason why researchers and scientists are looking for new strategies with less side effects. Nanoenzymes have intrinsic enzyme-like activities and can reduce the shortcomings of naturally occurring enzymes due to the ease of storage, high stability, less expensive, and enhanced efficiency. In this review, we have discussed various ways in which nanoenzymes are being used to diagnose and treat breast and ovarian cancer. For breast cancer, nanoenzymes and their multi-enzymatic properties can control the level of reactive oxygen species (ROS) in cells or tissues, for example, oxidase (OXD) and peroxidase (POD) activity can be used to generate ROS, while catalase (CAT) or superoxide dismutase (SOD) activity can scavenge ROS. In the case of ovarian cancer, most commonly nanoceria is being investigated, and also when folic acid is combined with nanoceria there are additional advantages like inhibition of beta galactosidase. Nanocarriers are also used to deliver small interfering RNA that are effective in cancer treatment. Studies have shown that iron oxide nanoparticles are actively being used for drug delivery, similarly ferritin carriers are used for the delivery of nanozymes. Hypoxia is a major factor in ovarian cancer, therefore MnO2-based nanozymes are being used as a therapy. For cancer diagnosis and screening, nanozymes are being used in sonodynamic cancer therapy for cancer diagnosis and screening, whereas biomedical imaging and folic acid gold particles are also being used for image guided treatments. Nanozyme biosensors have been developed to detect ovarian cancer. This review article summarizes a detailed insight into breast and ovarian cancers in light of nanozymes-based diagnostic and therapeutic approaches.


Asunto(s)
Neoplasias de la Mama , Neoplasias Ováricas , Humanos , Femenino , Neoplasias Ováricas/terapia , Neoplasias Ováricas/diagnóstico , Neoplasias de la Mama/terapia , Nanopartículas/química , Especies Reactivas de Oxígeno/metabolismo , Enzimas/metabolismo , Enzimas/química , Detección Precoz del Cáncer/métodos , Animales , Cerio
3.
Heliyon ; 10(4): e25591, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38370257

RESUMEN

The current study focuses the nanocomposites of Ag/WO3 was synthesized via hydrothermal method and extract of Aloe-vera gel was used. Various characterization techniques were used for the analysis of Ag/WO3 nanocomposites which includes SEM (scanning electron microscope), EDX (Energy dispersive spectroscopy), XRD (X-ray diffraction), FTIR (Fourier transform infrared), UV (ultraviolet-visible-spectroscopy) to tell about elemental composition, shape and crystalline structure, band gap, functional group. The presence of composition of elements O, W, Ag in Ag/WO3 nanocomposites was confirmed through EDX spectrum. The hexagonal crystal structure and the border peaks in Ag/WO3 nanocomposites were examined through XRD spectra. The Anti-oxidant activity was synthesized by using (DPPH) free Radical in Ag/WO3 nanocomposites. The outcomes of present study exhibited an excellent anti-oxidant activity and also indicated the reduction of stabilized free radical DPPH analysis using Aloe vera extract. The result revealed that the anti-oxidant activity of Ag/WO3 nanocomposites is essential for biomedical application and various industries.

4.
Sci Rep ; 14(1): 12711, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38830908

RESUMEN

The current research focuses on the development of Ag-ZnO heterostructures through a "bottom-up" approach involving the assembly and extraction of Aloe barbadensis Miller gel. These heterostructures composed of metals/semiconductor oxide display distinct and notable optical, electrical, magnetic, and chemical properties that are not found in single constituents and also exhibit photocatalytic applications. These synthesized heterostructures were characterized by XRD, FTIR, SEM, and UV-visible spectroscopy. The high peak intensity of the Ag/ZnO composite shows the high crystallinity. The presence of Ag-O, Zn-O, and O-H bonding is verified using FTIR analysis. SEM analysis indicated the formation of spherical shapes of Ag/ZnO heterostructures. The Zn, O, and Ag elements are further confirmed by EDX analysis. Ag-ZnO heterostructures exhibited excellent photocatalytic activity and stability against the degradation of tubantin red 8BL dye under visible light irradiation.

5.
ACS Omega ; 8(45): 42390-42397, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-38024666

RESUMEN

Manganese-doped bismuth ferrites were synthesized using the coprecipitation method with the green extract Azadirachta indica. Our incorporation of the transition element, manganese, into bismuth ferrites tackles the challenge of increased leakage current often observed in intrinsic bismuth ferrites. We gained key insights through a comprehensive examination of the structural, dielectric, and optical properties of these materials, utilizing Fourier transform infrared spectroscopy (FTIR), impedance spectroscopy, and UV-visible spectroscopy, respectively. The formation of an octahedral geometry was confirmed using the FTIR technique. UV-visible spectroscopy indicated that 2% Mn doping is optimal, while we obtained a low band gap energy (2.21 eV) and high refractive index (3.010) at this amount of doping. The manufactured materials exhibited the typical ferrite-like dielectric response, that is, the dielectric parameter gradually decreased as the frequency increased and then stayed constant in the high-frequency range. Using the diphenylpicrylhydrazyl (DPPH) free radical assay, we also examined the antioxidant activity of bismuth ferrites. We concluded that among different Mn-doped BiFeMnO3-based nanomaterials, the 2 wt % Mn-doped BiFeMnO3 shows the highest antioxidant activity. This finding substantiates the efficacy of the optimized material with regard to its potent antioxidant activity, positioning it as a promising candidate for potential biomedical applications.

6.
Appl Biochem Biotechnol ; 194(6): 2672-2683, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35239149

RESUMEN

The accurate and early diagnosis of infection is an important feature in the biomedical sciences for better treatment and to decrease the rate of morbidity associated with diseases. Doxycycline (DC) is a semisynthetic antibiotic that belongs to tetracycline family and usually prescribed to treat a variety of infections. The objective of the present research work was to develop a new radiopharmaceutical 99mTc-Doxycycline (99mTc-DC), by using SnCl2·2H2O as a reducing agent for diagnostic applications. It was confirmed through this study that 99mTc-DC possessed high radiolabeling yield (95%). In vitro studies were performed by incubating 99mTc-DC in human serum at 37 °C. The in vitro binding interaction of the labeled antibiotic was analyzed with bacterial strain (live Staphylococcus aureus cells), and its stability was further determined. Moreover, for in vivo infection imaging study, the infection was induced with S. aureus (gram positive) cells intramuscularly injected in mice models followed by biodistribution studies for 99mTc-DC that were performed. Biodistribution studies of 99mTc-DC showed that the radiotracer was significantly accumulated at the site of infection and indicated the renal route of excretion. Scintigraphic images obtained as a result of in vivo study showed good uptake of prepared radiotracer (99mTc-DC) in the infectious lesions at 1-, 4-, and 24-h post-injection. Target-to-non-target ratios for 99mTc-DC were significantly different for the infectious lesions and non-infected tissues and remained 2.13 ± 0.3 up to 24-h post-injection of 99mTc-DC. 99mTc-DC showed preferential binding to living bacterial infected sites as compared to other parts of the body, and thus it can be inferred that 99mTc-DC might be a potential candidate to diagnose the infection.


Asunto(s)
Infecciones Estafilocócicas , Staphylococcus aureus , Animales , Antibacterianos/metabolismo , Antibacterianos/farmacología , Doxiciclina/metabolismo , Doxiciclina/farmacología , Ratones , Modelos Animales , Radiofármacos , Infecciones Estafilocócicas/diagnóstico por imagen , Tecnecio , Distribución Tisular
7.
Nanomaterials (Basel) ; 12(17)2022 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-36080010

RESUMEN

In this study, novel hydrothermal ex situ synthesis was adopted to synthesize MoS2/WO3 heterostructures using two different molar ratios of 1:1 and 1:4. The "bottom-up" assembly was successfully developed to synthesize spherical and flaky-shaped heterostructures. Their structural, morphological, compositional, and bandgap characterizations were investigated through XRD, EDX, SEM, UV-Visible spectroscopy, and FTIR analysis. These analyses help to understand the agglomerated heterostructures of MoS2/WO3 for their possible photocatalytic application. Therefore, prepared heterostructures were tested for RhB photodegradation using solar light irradiation. The % efficiency of MoS2/WO3 composites for 30 min irradiation of 1:1 was 91.41% and for 1:4 was 98.16%. Similarly, the % efficiency of 1:1 MoS2/WO3 heterostructures for 60 min exposure was 92.68%; for 1:4, it was observed as 98.56%; and for 90 min exposure, the % efficiency of 1:1 was 92.41%, and 98.48% was calculated for 1:4 composites. The photocatalytic efficiency was further verified by reusability experiments (three cycles), and the characterization results afterward indicated the ensemble of crystalline planes that were responsible for the high efficiency. Moreover, these heterostructures showed stability over three cycles, indicating their future applications for other photocatalytic applications.

8.
Nanomaterials (Basel) ; 12(4)2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35214945

RESUMEN

Green synthesis differs in the way that the plant produces chemicals that act as reducing and stabilizing agents, and by adopting this green synthesis, we have synthesized silver nanoparticles (AgNPs) from the leaf and fruit extracts of Annona squamosa (also known as Sharifa), where these extracts have played an important role as reducing and capping agents. The nanoparticles were synthesized as the consequence of a reduction that happened between plant extracts and the precursor solution. The prepared AgNPs were then characterized using scanning electron microscopy, UV-Visible spectroscopy, and X-ray diffraction to study their morphology, optical response, and crystallinity. A single distinctive absorption peak of colloidal AgNPs samples was observed at 430 nm and 410 nm for leaf and fruit extract samples, having an optical bandgap of 2.97 eV and 2.88 eV, respectively, with a spherical shape having a diameter in the range of 35-90 nm and 15-50 nm, respectively, whilst XRD studies supported the FCC cubic structure of the mediated AgNPs. These green synthesized AgNPs have a wide variety of uses, particularly in the biomedical domain, where they have the potential to treat numerous diseases and are reported to be efficient against antibacterial, anti-cancer, and anti-diabetic activities.

9.
Sci Rep ; 12(1): 12978, 2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35902680

RESUMEN

The optoelectronic properties of the ternary Cd0.25Zn0.75Se alloy are reported under the influence of a high pressure ranging from 0 to 25 GPa, within a modified Becke-Jhonson potential using density functional theory. This alloy has a cubic symmetry, is mechanically stable, and its bulk modulus rises with pressure. It is observed to be a direct bandgap material with a bandgap energy that increases from 2.37 to 3.11 eV with rise in pressure. Pressure changes the optical and electronic properties, causing the absorption coefficient to rise and absorb visible green-to-violet light. The static dielectric constant, along with the static index of refraction, both increase under the influence of pressure. Optical constants, including dielectric constant, optical conductivity, refractive index, extinction coefficient, and reflection, are also investigated and discussed. This DFT forecast explores important research directions for the usage of the CdZnSe semiconductor alloys in the manufacturing of space photovoltaic and optoelectronic devices operating at different pressures.

10.
Sci Rep ; 11(1): 22783, 2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-34815474

RESUMEN

Dysregulation of non-coding microRNAs during the course of tumor development, invasion and/or progression to the distant organs, makes them a promising candidate marker for the diagnosis of cancer and associated malignancies. This exploratory study aims at evaluating the usefulness of plasma concentration of circulating mir-146a as a non-invasive biomarker for acute lymphoblastic leukemia (ALL). Total RNA including miRNA was isolated from 110 plasma samples of patients (n = 66), healthy controls (n = 24) and follow up (n = 20) cases and reverse transcribed. Relative concentrations were assessed using real-time quantitative PCR and fold-change was calculated by 2-ΔΔCt method. Finally, relative concentrations were correlated to clinicopathological factors. Patients (n = 66) were analyzed to determine fold expression of miR-146a in plasma samples of ALL. Before chemotherapy, pediatric (n = 42) and adult (n = 24) showed overexpression of miR-146a compared with healthy controls (P < 0.0001). There was no effect of age and gender on mir-146a expression in plasma. mirR-146a expression was independent of clinical and hematological features. Moreover, miR-146a levels in plasma of paired samples (n = 20) after treatment showed significant decrease in expression (P < 0.001). Expression of plasma miR-146a may be utilized as non-invasive marker to diagnose and predict prognosis in pediatric and adult patients with ALL. Moreover predicted targets may be utilized for ALL therapy in future.


Asunto(s)
Biomarcadores de Tumor/genética , Ácidos Nucleicos Libres de Células/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Adolescente , Adulto , Biomarcadores de Tumor/sangre , Estudios de Casos y Controles , Ácidos Nucleicos Libres de Células/análisis , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , MicroARNs/sangre , Persona de Mediana Edad , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Pronóstico , Adulto Joven
11.
Biomed Phys Eng Express ; 7(3)2021 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-33862602

RESUMEN

In this research work, a simple homemade cubic phantom was designed to validate the Image-Guided Radiotherapy (IGRT) set up and verified with the help of tungsten fiducial markers (size 2-3 mm) inserted into the cubic phantom. Phantom made up of Styrofoam, was scanned with the help of 16 slice Toshiba CT scanner where each slice was of 1 mm thickness and HU level set to -1000. A radio-opaque contrast medium was rubbed on the phantom to visualize the scanner images. Once the iso-center had been marked on a phantom with the help of in-room positioning laser and the fields (RT-LAT and AP) were applied on the contoured body of the phantom in Varian's ARIA-11 Eclipse dosimeter software, the same position of the phantom was reproduced on Varian's Linear Accelerator DHX. Known shifts of 3.0 to 30.0 mm from the marked iso-center were applied on the phantom by moving the couch in all six directions one by one. On each applied couch shift, an x-ray image of the phantom was acquired with the help of an MV portal imager of Linac in AP and RT-LAT direction. This image was superimposed with a reference image of phantom and shift accuracy calculated by ARIA-11 software was noted down. It turned out that irrespective of the position of the phantom on the couch, the calculated corrected shift and deviation from reference position was always between ± 1-2 mm which is the required accuracy for IGRT according to International Atomic Energy Agency (IAEA). This process was repeated 40 times and each time, the corrected shift came out to be ± 1-2 mm. We can conclude that our system is safe and accurate enough to perfectly position the actual patient for IGRT.


Asunto(s)
Radioterapia Guiada por Imagen , Marcadores Fiduciales , Humanos , Aceleradores de Partículas , Fantasmas de Imagen , Tungsteno
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