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1.
PLoS One ; 19(6): e0301479, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38861572

RESUMEN

This article provides insights in designing a dielectrically modulated biosensor by adopting high-k stacked gate oxide proposition in a bi-metal hetero-juncture Tunnel Field Effect Transistor (BM-SO-HTFET) with Si0.6Ge0.4 source. The integrated effect of heterojunction and stacked gate oxide leads to enhanced electrical performance of the proposed device in terms of carrier mobility and suppressed leakage current. Nano-cavity engraved beneath the bi-metal gate structure across the source/channel end acts the binding site of the biomolecules to be detected. This Configuration leads to improved control of biomolecules over source/channel tunnelling rate and the same is reflected in the sensing ability of the device while extracting the ON current sensitivity (SON) of the sensor. The reported biosensor is simulated using Silvaco ATLAS calibrated simulation framework. The analysis of the device sensitivity is carried out varying dielectric constants (k) of various biomolecules, both neutral as well as charged. Our study reveals that BM-SO-HTFET with Ge mole fraction composition x = 0.4 exhibits sensitivity as high as 4.1 × 1010 for neutral biomolecules and 3.2 × 1011 for positively charged biomolecules with k = 12. Furthermore, a transient response profile for the drain current with various biomolecules is explored to determine the varying settling time. From the simulation results, it is noted that BM-SO-HTFET exhibits ON current sensitivity of 4.1 × 1010 and 3.2 × 1011 for neutral and charged biomolecules respectively. In addition to this, for highly sensitive and real time detection of biomolecules, the impact of temperature and certain non-ideal factors drifting from ideal case of fully filled cavity have also been considered to analyze its optimum sensing performance.


Asunto(s)
Técnicas Biosensibles , Transistores Electrónicos , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Óxidos/química , Germanio/química , Silicio/química
2.
BMC Res Notes ; 17(1): 180, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926863

RESUMEN

OBJECTIVE: Germanium, an important component of electronics, is considered by many global economies as a critical raw material. Therefore, investigating its potential new sources is crucial for prospective technology development. This paper presents the investigation results on the leaching of liquation-feeding furnace dross using sulfuric and oxalic acid solutions. RESULTS: The dross contained mostly zinc (68.0% wt.) but also elevated germanium concentration (0.68% wt.). The influence of temperature, time, initial acid concentration, and liquid-to-solid phase ratio (L:S) was examined. It was found that germanium availability via leaching is limited-maximum leaching yields using aqueous solutions of sulfuric and oxalic acids were 60% (80 °C, 2 h, 15% wt. H2SO4, L:S 25:1) and 57% (80 °C, 3 h, 12.5% wt. H2C2O4, L:S 10:1), respectively.


Asunto(s)
Germanio , Ácidos Sulfúricos , Germanio/química , Ácidos Sulfúricos/química , Ácido Oxálico/química , Temperatura , Residuos Electrónicos/análisis
3.
Radiat Prot Dosimetry ; 200(8): 721-738, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38690853

RESUMEN

This paper describes a procedure for the estimation of 241Am and 239Pu activity present in the human tissue by measuring the depth of contaminant using a portable Planar High Purity Germanium detector (HPGe). The ratios of photopeak counts of X-rays or gammas obtained with the detector coupled to collimator are calculated for the estimation of depth of the contaminant and the optimum one is determined. Since Minimum Detectable Activities (MDA) for the detector coupled to a collimator are higher than that of bare detector, activity must be estimated using bare detector, after locating the contaminant. Two methods are described for the estimation of plutonium coexisting with 241Am: (i) Abundance and isotopic correction for 239Pu (ii) and 239Pu:241Am ratio. The procedure to estimate 239Pu when plutonium isotopes alone are present is also established. An optimum monitoring period to detect the minimum value of intake for both radionuclides corresponding to chelation therapy and excision is also derived.


Asunto(s)
Americio , Germanio , Plutonio , Plutonio/análisis , Americio/análisis , Humanos , Germanio/análisis , Monitoreo de Radiación/métodos , Monitoreo de Radiación/instrumentación , Dosis de Radiación , Radiometría/métodos , Radiometría/instrumentación
4.
STAR Protoc ; 5(2): 103039, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38669138

RESUMEN

In this protocol, we present a facile nanoscale thermal mapping technique for electronic devices by use of atomic force microscopy and a phase change material Ge2Sb2Te5. We describe steps for Ge2Sb2Te5 thin film coating, Ge2Sb2Te5 temperature calibration, thermal mapping by varying heater power, and thermal mapping by varying heating time. The protocol can be applied for resolving surface temperatures of various operational microelectronic devices with a nanoscale precision. For complete details on the use and execution of this protocol, please refer to Cheng et al.1.


Asunto(s)
Microscopía de Fuerza Atómica , Microscopía de Fuerza Atómica/métodos , Nanotecnología/métodos , Temperatura , Germanio/química
5.
Anal Chem ; 96(14): 5694-5701, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38538547

RESUMEN

Immunochromatography is a commonly used immediate detection technique, using signal labels to generate detection signals for rapid medical diagnosis. However, its detection sensitivity is affected by background fluorescence caused by the excitation light source. We have developed an immunochromatographic test strip using Zn2GeO4:Mn2+ (ZGM) persistent luminescent nanoparticles (PLNPs) for immediate fluorescence detection and highly sensitive persistent luminescence (PersL) detection without background fluorescence interference. ZGM emits a strong green light when exposed to ultraviolet (UV) excitation, and its green PersL can persist for over 30 min after the excitation light is turned off. We modified the surface of ZGM with heparin-binding protein (HBP) antibodies to create immunochromatographic test strips for the detection of HBP as the target analyte. Under UV excitation, the chromatography test paper can be visually observed at concentrations as low as 25 ng/mL. After the excitation light source is switched off, PersL can achieve a detection limit of 4.7 ng/mL without background interference. This dual-mode immunochromatographic detection, based on ZGM, shows great potential for in vitro diagnostic applications.


Asunto(s)
Germanio , Luminiscencia , Nanopartículas , Nanopartículas/química , Óxidos , Cromatografía de Afinidad/métodos
6.
PLoS One ; 19(3): e0299039, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38427648

RESUMEN

The chemical etching of germanium in Br2 environment at elevated temperatures is described by the Michaelis-Menten equation. The validity limit of Michaelis-Menten kinetics is subjected to the detailed analysis. The steady-state etching rate requires synergy of two different process parameters. High purity gas should be directed to the substrate on which intermediate reaction product does not accumulate. Theoretical calculations indicate that maximum etching rate is maintained when 99.89% of the germanium surface is covered by the reaction product, and 99.9999967% of the incident Br2 molecules are reflected from the substrate surface. Under these conditions, single GeBr2 molecule is formed after 30 million collisions of Br2 molecules with the germanium surface.


Asunto(s)
Germanio , Modelos Químicos , Algoritmos , Cinética , Física
7.
Adv Sci (Weinh) ; 11(20): e2307060, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38516744

RESUMEN

Biodegradable nanomaterials can significantly improve the safety profile of nanomedicine. Germanium nanoparticles (Ge NPs) with a safe biodegradation pathway are developed as efficient photothermal converters for biomedical applications. Ge NPs synthesized by femtosecond-laser ablation in liquids rapidly dissolve in physiological-like environment through the oxidation mechanism. The biodegradation of Ge nanoparticles is preserved in tumor cells in vitro and in normal tissues in mice with a half-life as short as 3.5 days. Biocompatibility of Ge NPs is confirmed in vivo by hematological, biochemical, and histological analyses. Strong optical absorption of Ge in the near-infrared spectral range enables photothermal treatment of engrafted tumors in vivo, following intravenous injection of Ge NPs. The photothermal therapy results in a 3.9-fold reduction of the EMT6/P adenocarcinoma tumor growth with significant prolongation of the mice survival. Excellent mass-extinction of Ge NPs (7.9 L g-1 cm-1 at 808 nm) enables photoacoustic imaging of bones and tumors, following intravenous and intratumoral administrations of the nanomaterial. As such, strongly absorbing near-infrared-light biodegradable Ge nanomaterial holds promise for advanced theranostics.


Asunto(s)
Germanio , Técnicas Fotoacústicas , Fototerapia , Animales , Ratones , Técnicas Fotoacústicas/métodos , Germanio/química , Fototerapia/métodos , Modelos Animales de Enfermedad , Rayos Láser , Nanopartículas/química , Nanopartículas del Metal/química , Nanopartículas del Metal/uso terapéutico , Materiales Biocompatibles/química , Línea Celular Tumoral , Neoplasias/terapia , Neoplasias/diagnóstico por imagen , Femenino
8.
Environ Sci Pollut Res Int ; 31(12): 18485-18493, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38347351

RESUMEN

The solid waste produced from the germanium extraction process has attached much attention to its potential germanium sources. However, the elemental distribution of solid waste is still unclear. Therefore, the solid waste was studied using a sequential extraction procedure and characterizations including XRD, FTIR, XPS, SEM-EDS, and XAFS. It has been found that Ca, S, Fe, and Si could present crystal occurrence forms such as calcium sulfate, iron oxide hydroxide, or quartz. Furthermore, Si and Al can form a certain amount of amorphous substance. Accordingly, the sequential leaching results tell that Ca and S can be mostly leached out in pure water or weak acid solution, and more than 50% of Fe, Al, and Si were leached out in the reducible or oxidizable environment. Additionally, a part of S could be associated with Pb, generating a mostly Pb-bearing sulfate structure. Most of Zn was leached out from the reducible step, and only a very small part of Zn presented in the residual state, indicating that the majority of Zn might exist in an oxidation state and a small amount of Zn is associated in the amorphous phase. In terms of Ge, As, and Cr, almost all of them existed in the residual state. Ge should be in the occurrence of Si/Al amorphous structure. Similarly, Cr should be most likely to associate with silicates. Furthermore, As is mainly associated with iron mineral through the formation of the binuclear bidentate corner-sharing complex.


Asunto(s)
Germanio , Metales Pesados , Metales Pesados/análisis , Residuos Sólidos , Plomo , Silicatos
9.
Eur J Nucl Med Mol Imaging ; 51(4): 954-964, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38012446

RESUMEN

PURPOSE: A solid-state PET/CT system uses bismuth germanium oxide (BGO) scintillating crystals coupled to silicon photomultipliers over an extended 32 cm axial field-of-view (FOV) to provide high spatial resolution and very high sensitivity. Performance characteristics were determined for this digital-BGO system, including NEMA and EARL standards. METHODS: Spatial resolution, scatter fraction (SF), noise equivalent count rate (NECR), sensitivity, count rate accuracy, and image quality (IQ) were evaluated for the digital-BGO system as per NEMA NU 2-2018, at 2 sites of first clinical install. System energy resolution was measured. Bayesian penalized-likelihood reconstruction (BPL) was used for IQ. EARL Standards 2 studies were reconstructed by BPL combined with a contrast-enhancing deep learning algorithm. An Esser PET phantom was evaluated. Three patient examples were obtained with low-dose radiotracer activity: 2 MBq/kg of [18F]FDG ([18F]-2-fluoro-2-deoxy-D-glucose), 2.3 MBq/kg [68Ga]Ga-DOTA-TATE ([dodecane tetra-acetic acid,Tyr3]-octreotate), and 14.5 MBq/kg [82Rb]RbCl ([82Rb]-rubidium-chloride). Total scan times were ≤ 8 min. RESULTS: NEMA sensitivity was 47.6 cps/kBq at the axial center. Spatial resolution at 1 cm from the center axis was ≤4.5 mm (filtered back projection) and ≤3.8 mm (ordered subset expectation maximization). SF was 35.6%, count rate accuracy was 2.16%, and peak NECR was 485.2 kcps at 16.9 kBq/mL. Contrast for IQ was 61.1 to 90.7% (smallest to largest sphere) with background variations from 7.6 to 2.1%, and a "lung" error of 4.7%. The average detector energy resolution was 9.67%. Image quality for patient scans was good. EARL Standards 2 criteria were robustly met and Esser phantom features ≥4.8 mm were resolved at 2 min per bed position. CONCLUSION: A solid-state 32 cm axial FOV digital-BGO PET/CT system provides good spatial and energy resolution, high count rates, and superior NEMA sensitivity in its class, enabling fast clinical acquisitions with low-dose radiotracer activity.


Asunto(s)
Bismuto , Germanio , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones , Humanos , Teorema de Bayes , Tomografía de Emisión de Positrones/métodos , Fantasmas de Imagen , Estándares de Referencia
10.
Int J Mol Sci ; 24(21)2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37958931

RESUMEN

We present the stabilization of halide-terminated Ge nanoparticles prepared via a disproportionation reaction of metastable Ge(I)X solutions with well-defined size distribution. Further tailoring of the stability of the Ge nanoparticles was achieved using variations in the substituent. Ge nanoparticles obtained in this way are readily dispersed in organic solvents, long-term colloidally stable, and are perfect prerequisites for thin-film preparation. This gives these nanomaterials a future in surface-dependent optical applications, as shown for the halide-terminated nanoparticles.


Asunto(s)
Germanio , Nanopartículas , Nanoestructuras , Tecnología
11.
J Transl Med ; 21(1): 795, 2023 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-37940963

RESUMEN

With the development of organic germanium and nanotechnology, germanium serves multiple biological functions, and its potential value in biochemistry and medicine has increasingly captured the attention of researchers. In recent years, germanium has gradually gained significance as a material in the field of biomedicine and shows promising application prospects. However, there has been a limited amount of research conducted on the biological effects and mechanisms of germanium, and a systematic evaluation is still lacking. Therefore, the aim of this review is to systematically examine the application of germanium in the field of biomedicine and contribute new insights for future research on the functions and mechanisms of germanium in disease treatment. By conducting a comprehensive search on MEDLINE, EMBASE, and Web of Science databases, we systematically reviewed the relevant literature on the relationship between germanium and biomedicine. In this review, we will describe the biological activities of germanium in inflammation, immunity, and antioxidation. Furthermore, we will discuss its role in the treatment of neuroscience and oncology-related conditions. This comprehensive exploration of germanium provides a valuable foundation for the future application of this element in disease intervention, diagnosis, and prevention.


Asunto(s)
Germanio , Nanotecnología
12.
Radiat Prot Dosimetry ; 199(15-16): 1848-1852, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37819285

RESUMEN

A new in-vivo counting system that functions as both a whole-body counter (WBC) and a lung counter (LC) was developed at the QST to enhance its dose assessment capability. This paper presents an overview of this system and the results of its performance tests. For use of the system as a WBC, three high purity germanium (HPGe) detectors installed in a 20-cm-thick iron shielding chamber are linearly arrayed over a subject lying on the bed, whereas two of the three HPGe detectors are placed over the subject's chest from side to side when using the system as an LC. The new in-vivo system was calibrated using three de-facto phantoms owned by the QST: an adult-male BOttle Manikin ABsorption (BOMAB) phantom, a Lawrence Livermore National Laboratory (LLNL) phantom and a Japan Atomic Energy Research Institute (JAERI) phantom. Monte Carlo simulations were also performed to determine an optimum location for the three detector array in the WBC mode and revealed that the peak efficiency for the BOMAB phantom (662 keV) was little varied as long as the middle detector was placed above the thorax and abdomen parts of the phantom. The calculated peak efficiencies agreed well with the observed peak efficiencies for photons with energies over 100 keV. For lung counting, a tentative Minimum Detectable Activity of 241Am was evaluated as 9.5 Bq for a counting time of 30 minutes, and a Japanese male subject with an average chest wall thinness (2.27 cm). The developed system is now ready for use.


Asunto(s)
Americio , Germanio , Masculino , Humanos , Tórax , Recuento Corporal Total , Fantasmas de Imagen , Método de Montecarlo
13.
Phys Med Biol ; 68(18)2023 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-37681308

RESUMEN

Objective.The results of a follow-up experiment investigating a novel method for sub-milimetre range verification (RV) in proton therapy (PT) are presented.Approach.The method consists of implanting a hadron tumour marker (HTM) near the planned treatment volume, and measuring theγ-ray signals emitted as a result of activation by the proton beam. These signals are highly correlated with the energy of the beam impinging on the HTM and can provide an absolute measurement of the range of the beam relative to the position of the HTM, which is independent of any uncertainties in beam delivery.Main results.Three candidate HTM materials were identified and combined into a single composite HTM, which makes use of the strongest reaction in each material. The setup of the previous experiment was improved on by using high-purity germanium detectors to measure theγ-ray signal with a higher resolution than was previously achieved. A PMMA phantom was also used to simulate theγ-ray background from tissue activation. HTM RV using the data collected in this study yielded range measurements whose average deviation from the expected value was 0.13(22)mm.Significance.Range uncertainty in PT limits the prescribed treatment plan for cancer patients with large safety margins and constrains the direction of the proton beam in relation to any organ at risk. The sub-milimetre range uncertainty achieved in this study using HTM RV, if implemented clinically, would allow for a reduction in the size of safety margins, increasing the therapeutic window for PT.


Asunto(s)
Germanio , Terapia de Protones , Humanos , Protones , Biomarcadores de Tumor , Fantasmas de Imagen
14.
J Environ Manage ; 347: 119043, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37776794

RESUMEN

Advanced high-tech applications for communication, renewable energy, and display, heavily rely on technology critical elements (TCEs) such as indium, gallium, and germanium. Ensuring their sustainable supply is a pressing concern due to their high economic value and supply risks in the European Union. Recovering these elements from end-of-life (EoL) products (electronic waste: e-waste) offers a potential solution to address TCEs shortages. The review highlights recent advances in pre-treatment and hydrometallurgical and biohydrometallurgical methods for indium, gallium, and germanium recovery from EoL products, including spent liquid crystal displays (LCDs), light emitting diodes (LEDs), photovoltaics (PVs), and optical fibers (OFs). Leaching methods, including strong mineral and organic acids, and bioleaching, achieve over 95% indium recovery from spent LCDs. Recovery methods emphasize solvent extraction, chemical precipitation, and cementation. However, challenges persist in separating indium from other non-target elements like Al, Fe, Zn, and Sn. Promising purification involves solid-phase extraction, electrochemical separation, and supercritical fluid extraction. Gallium recovery from spent GaN and GaAs LEDs achieves 99% yield via leaching with HCl after annealing and HNO3, respectively. Sustainable gallium purification techniques include solvent extraction, ionic liquid extraction, and nanofiltration. Indium and gallium recovery from spent CIGS PVs achieves over 90% extraction yields via H2SO4 with citric acid-H2O2 and alkali. Although bioleaching is slower than chemical leaching (several days versus several hours), indirect bioleaching shows potential, achieving 70% gallium extraction yield. Solvent extraction and electrolysis exhibit promise for pure gallium recovery. HF or alkali roasting leaches germanium with a high yield of 98% from spent OFs. Solvent extraction achieves over 90% germanium recovery with minimal silicon co-extraction. Solid-phase extraction offers selective germanium recovery. Advancements in optimizing and implementing these e-waste recovery protocols will enhance the circularity of these TCEs.


Asunto(s)
Residuos Electrónicos , Galio , Germanio , Residuos Electrónicos/análisis , Indio/química , Peróxido de Hidrógeno , Reciclaje/métodos , Tecnología , Galio/química , Solventes , Álcalis
15.
Environ Geochem Health ; 45(11): 8803-8822, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37755578

RESUMEN

Mining of precious metals contributes to environmental pollution, especially in coastal areas, and conventional treatment methods are not always effective in removing metal contaminants. Some of these metals, such as gadolinium, germanium and gallium, have caused increasing concern worldwide, as little is known about their current concentrations in the aquatic environment and their biological significance. Therefore, the aim of this study was to determine for the first time the variation of average G(s) concentrations (gallium, gadolinium and germanium) by month/season/site differences along the coast of Istanbul. The ecological risk index was calculated to assess the contamination of seawater and to serve as a diagnostic tool for the mitigation of water pollution. The average distribution G(s) in seawater was in the following order: Ga > Gd > Ge. In addition, the potential ecological risk in the sampling areas ranged from 68 to 1049. Of the three metals, Gd poses the highest ecological risk (grade III). In the spatial distribution of ecological risks, Gd mainly originated from discharges from wastewater treatment plants. Therefore, the sources of the anthropogenic Gd anomaly in wastewater should be identified, as this indicates the possibility of human exposure to potentially harmful anthropogenic compounds.


Asunto(s)
Galio , Germanio , Metales Pesados , Contaminantes Químicos del Agua , Humanos , Gadolinio/análisis , Agua de Mar , Contaminación Ambiental , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Medición de Riesgo
16.
Adv Healthc Mater ; 12(27): e2301151, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37421228

RESUMEN

Severe bone defects accompanied by vascular and peripheral nerve injuries represent a huge orthopedic challenge and are often accompanied by the risk of infection. Thus, biomaterials with antibacterial and neurovascular regeneration properties are highly desirable. Here, a newly designed biohybrid biodegradable hydrogel (GelMA) containing copper ion-modified germanium-phosphorus (GeP) nanosheets, which act as neuro-vascular regeneration and antibacterial agents, is designed. The copper ion modification process serves to improve the stability of the GeP nanosheets and offers a platform for the sustained release of bioactive ions. Study findings show that GelMA/GeP@Cu has effective antibacterial properties. The integrated hydrogel can significantly boost the osteogenic differentiation of bone marrow mesenchymal stem cells, facilitate angiogenesis in human umbilical vein endothelial cells, and up-regulate neural differentiation-related proteins in neural stem cells in vitro. In vivo, in the rat calvarial bone defect mode, the GelMA/GeP@Cu hydrogel is found to enhance angiogenesis and neurogenesis, eventually contributing to bone regeneration. These findings indicate that in the field of bone tissue engineering, GelMA/GeP@Cu can serve as a valuable biomaterial for neuro-vascularized bone regeneration and infection prevention.


Asunto(s)
Germanio , Osteogénesis , Ratas , Humanos , Animales , Hidrogeles/farmacología , Cobre/farmacología , Germanio/farmacología , Fósforo/farmacología , Regeneración Ósea , Materiales Biocompatibles/farmacología , Células Endoteliales de la Vena Umbilical Humana , Antibacterianos/farmacología
17.
Luminescence ; 38(10): 1750-1757, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37464921

RESUMEN

Samarium (Sm3+ )-doped glass has sparked a rising interest in demonstrating a noticeable emission in the range of 400-700, which is advantageous in solid-state lasers in the visible region, colour displays, undersea communication, and optical memory devices. This study reports the fabrication of Sm3+ -doped bismuth-germanium-borate glasses were established using a standard melt-quenching technique and inspection by absorption, steady-state luminescence, and transient studies. The typical peaks of Sm3+ ions were detected in the visible range under 403 nm excitation. A strong emission band was detected at 599 nm that resembles the 4 G5/2 →6 H7/2 transition of Sm3+ ions for BGBiNYSm0.5 glass. Furthermore, a reddish-orange (coral) luminescence at 646 nm that resembles the 4 G5/2 →6 H9/2 transition was also perceived. The stimulated emission cross-section of 4 G5/2 level for BGBiNYSm0.5 glass was 0.39 × 10-22  cm2 . Lifetime of the 4 G5/2 level was enhanced for the BGBiNYSm0.5 glass and decreased with an increase in active ion concentrations. The lifetime quenching of ions at the metastable state was because of energy transfer among Sm3+ ions by cross-relaxation channels. Commission Internationale de l'Éclairage (CIE) coordinates were evaluated from the emission spectra. Moreover, all the findings recommend these glass as light-emitting materials in the coral region at 599 nm for solid-state lighting applications.


Asunto(s)
Germanio , Samario , Bismuto , Boratos , Luminiscencia , Vidrio , Iones
18.
Int J Mol Sci ; 24(12)2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37373364

RESUMEN

Polydentate ligands are used for thermodynamic stabilization of tetrylenes-low-valent derivatives of Group 14 elements (E = Si, Ge, Sn, Pb). This work shows by DFT calculations how the structure (the presence or absence of substituents) and type (alcoholic, Alk, or phenolic, Ar) of tridentate ligands 2,6-pyridinobis(1,2-ethanols) [AlkONOR]H2 and 2,6-pyridinobis(1,2-phenols) [ArONOR]H2 (R = H, Me) may affect the reactivity or stabilization of tetrylene, indicating the unprecedented behavior of Main Group elements. This enables the unique control of the type of the occurring reaction. We found that unhindered [ONOH]H2 ligands predominantly led to hypercoordinated bis-liganded {[ONOH]}2Ge complexes, where an E(+2) intermediate was inserted into the ArO-H bond with subsequent H2 evolution. In contrast, substituted [ONOMe]H2 ligands gave [ONOMe]Ge: germylenes, which may be regarded as kinetic stabilized products; their transformation into E(+4) species is also thermodynamically favorable. The latter reaction is more probable for phenolic [ArONO]H2 ligands than for alcoholic [AlkONO]H2. The thermodynamics and possible intermediates of the reactions were also investigated.


Asunto(s)
Germanio , Teoría Funcional de la Densidad , Ligandos , Termodinámica , Fenoles/química , Proteínas Tirosina Quinasas Receptoras
19.
Nanoscale ; 15(27): 11544-11559, 2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37366254

RESUMEN

Photoacoustic (PA) imaging using contrast agents with strong near-infrared-II (NIR-II, 1000-1700 nm) absorption enables deep penetration into biological tissue. Besides, biocompatibility and biodegradability are essential for clinical translation. Herein, we developed biocompatible and biodegradable germanium nanoparticles (GeNPs) with high photothermal stability as well as strong and broad absorption for NIR-II PA imaging. We first demonstrate the excellent biocompatibility of the GeNPs through experiments, including the zebrafish embryo survival rates, nude mouse body weight curves, and histological images of the major organs. Then, comprehensive PA imaging demonstrations are presented to showcase the versatile imaging capabilities and excellent biodegradability, including in vitro PA imaging which can bypass blood absorption, in vivo dual-wavelength PA imaging which can clearly distinguish the injected GeNPs from the background blood vessels, in vivo and ex vivo PA imaging with deep penetration, in vivo time-lapse PA imaging of a mouse ear for observing biodegradation, ex vivo time-lapse PA imaging of the major organs of a mouse model for observing the biodistribution after intravenous injection, and notably in vivo dual-modality fluorescence and PA imaging of osteosarcoma tumors. The in vivo biodegradation of GeNPs is observed not only in the normal tissue but also in the tumor, making the GeNPs a promising candidate for clinical NIR-II PA imaging applications.


Asunto(s)
Germanio , Nanopartículas , Técnicas Fotoacústicas , Ratones , Animales , Medios de Contraste/farmacología , Técnicas Fotoacústicas/métodos , Distribución Tisular , Pez Cebra , Fototerapia/métodos
20.
Chem Commun (Camb) ; 59(47): 7251-7254, 2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37222547

RESUMEN

We report the synthesis of a trimetallic mixed-valence Ge(I)/Ge(II)/Ge(III) trihydride, which presents a structural novel motif among systems of the type (XMH)n (M = group 14 metal). In terms of reactivity (ArNiPr2)GeGe(ArNiPr2)(H)Ge(ArNiPr2)(H)2 can act as a source of both the Ge(II) and Ge(IV) hydrides via Ge-H reductive elimination from the central metal centre involving two different regiochemistries.


Asunto(s)
Germanio , Germanio/química , Hidrógeno/química , Oxidación-Reducción , Estrés Oxidativo
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