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1.
Nature ; 629(8011): 335-340, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38658759

RESUMO

Flexible and large-area electronics rely on thin-film transistors (TFTs) to make displays1-3, large-area image sensors4-6, microprocessors7-11, wearable healthcare patches12-15, digital microfluidics16,17 and more. Although silicon-based complementary metal-oxide-semiconductor (CMOS) chips are manufactured using several dies on a single wafer and the multi-project wafer concept enables the aggregation of various CMOS chip designs within the same die, TFT fabrication is currently lacking a fully verified, universal design approach. This increases the cost and complexity of manufacturing TFT-based flexible electronics, slowing down their integration into more mature applications and limiting the design complexity achievable by foundries. Here we show a stable and high-yield TFT platform for the fabless manufacturing of two mainstream TFT technologies, wafer-based amorphous indium-gallium-zinc oxide and panel-based low-temperature polycrystalline silicon, two key TFT technologies applicable to flexible substrates. We have designed the iconic 6502 microprocessor in both technologies as a use case to demonstrate and expand the multi-project wafer approach. Enabling the foundry model for TFTs, as an analogy of silicon CMOS technologies, can accelerate the growth and development of applications and technologies based on these devices.


Assuntos
Silício , Transistores Eletrônicos , Silício/química , Eletrônica/instrumentação , Índio/química , Gálio/química , Óxido de Zinco/química , Desenho de Equipamento , Semicondutores
2.
Food Chem ; 445: 138747, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38387317

RESUMO

A new 3D metal-organic framework {[Cd16(tr2btd)10(dcdps)16(H2O)3(EtOH)]∙15DMF}n (MOF 1, tr2btd = 4,7-di(1,2,4-triazol-1-yl)benzo-2,1,3-thiadiazole, H2dcdps = 4,4'-sulfonyldibenzoic acid) was obtained and its luminescent properties were studied. MOF 1 exhibited bright blue-green luminescence with a high quantum yield of 74 % and luminescence quenching response to a toxic natural polyphenol gossypol and luminescence enhancement response to some trivalent metal cations (Fe3+, Cr3+, Al3+ and Ga3+). The limit of gossypol detection was 0.20 µM and the determination was not interfered by the components of the cottonseed oil. The limit of detection of gallium(III) was 1.1 µM. It was demonstrated that MOF 1 may be used for distinguishing between the genuine sunflower oil and oil adulterated by crude cottonseed oil through qualitative luminescent and quantitative visual gossypol determination.


Assuntos
Gálio , Gossipol , Estruturas Metalorgânicas , Petróleo , Óleo de Sementes de Algodão , Luminescência , Culinária
3.
J Mater Chem B ; 12(9): 2313-2323, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38268450

RESUMO

As a multifunctional material, gallium-based liquid metal (LM) mixtures with metal particles dispersed in the LM environment display many excellent and intriguing properties. In this study, biomaterials were prepared by mixing Fe particles with LM for easily manageable photothermal or electromagnetic therapy and evaluated. Clinically, the fabricated 5%Fe/LM sample was injectable and radiopaque, which allowed its smooth delivery through a syringe to the target tissues, where it could help achieve clear imaging under CT. Meanwhile, because of the loading of Fe particles, the 5%Fe/LM possessed a magnetic property, implying a high manipulation capability. According to the experiments, the capsule containing 5%Fe/LM when placed in an isolated pig large intestine could move as desired to the designated position through an external magnet. Further, the biosafety and low toxicity of the 5%Fe/LM were confirmed by cytotoxicity tests in vitro, and the temperature changes at the interface between the 5%Fe/LM and intestinal tissue after near-infrared (NIR) laser irradiation were determined through theoretical modeling and numerical simulation data analysis. Due to the excellent photothermal and magnetothermal effects of LM, the temperature of the 5%Fe/LM injected into the rabbit abdominal cavity could significantly increase under NIR laser or alternating magnetic field (AMF) administration. As a novel functional biomaterial, the 5%Fe/LM exhibited promising potential for designated position movement and photothermal or magnetothermal therapy in the near future.


Assuntos
Gálio , Magnetoterapia , Animais , Coelhos , Suínos , Materiais Biocompatíveis , Campos Magnéticos
4.
ACS Appl Mater Interfaces ; 15(33): 39143-39156, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37579188

RESUMO

Resistant bacterial infection remains a severe public health threat, and conventional antibiotic drugs work poorly in effectively treating infectious diseases. Here, we developed gallium-based nanodots (Ga NDs), consisting of specific disruption of bacterial iron ability, to treat multidrug-resistant (MDR) Gram-negative bacteria-infected diseases. The Ga NDs significantly suppress the proliferation of two typical MDR bacteria strains (P. aeruginosa and ESBL E. coli) compared with clinically used antibacterial drugs, including penicillin and levofloxacin. Ga NDs could also disrupt the biofilms of these two bacterial strains. In P. aeruginosa infected pneumonia and ESBL E. coli infected acute liver abscess models, the Ga NDs enable substantial inhibition of bacterial growth and reduce the organs' inflammation that resulted in significant improvement of survival. Further, the Ga NDs demonstrated excellent biocompatibility and biosafety characteristics. Together, we believe that our gallium containing nanotherapeutics are expected to be developed into promising alternative therapies to combat drug-resistant bacterial infection.


Assuntos
Gálio , Abscesso Hepático , Pneumonia Bacteriana , Humanos , Gálio/farmacologia , Escherichia coli , Antibacterianos/farmacologia , Bactérias , Testes de Sensibilidade Microbiana
5.
Mol Pharm ; 20(8): 4058-4070, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37471668

RESUMO

There is a major need for the development of new therapeutics to combat antibiotic-resistant Staphylococcus aureus. Recently, gallium (Ga)-based complexes have shown promising antimicrobial effects against various bacteria, including multidrug-resistant organisms, by targeting multiple heme/iron-dependent metabolic pathways. Among these, Ga protoporphyrin (GaPP) inhibits bacterial growth by targeting heme pathways, including aerobic respiration. Ga(NO3)3, an iron mimetic, disrupts elemental iron pathways. Here, we demonstrate the enhanced antimicrobial activity of the combination of GaPP and Ga(NO3)3 against methicillin-resistant S. aureus (MRSA) under iron-limited conditions, including small colony variants (SCV). This therapy demonstrated significant antimicrobial activity without inducing slow-growing SCV. We also observed that the combination of GaPP and Ga(NO3)3 inhibited the MRSA catalase but not above that seen with Ga(NO3)3 alone. Neither GaPP nor Ga(NO3)3 alone or their combination inhibited the dominant superoxide dismutase expressed (SodA) under the iron-limited conditions examined. Intranasal administration of the combination of the two compounds improved drug biodistribution in the lungs compared to intraperitoneal administration. In a murine MRSA lung infection model, we observed a significant increase in survival and decrease in MRSA lung CFUs in mice that received combination therapy with intranasal GaPP and Ga(NO3)3 compared to untreated control or mice receiving GaPP or Ga(NO3)3 alone. No drug-related toxicity was observed as assessed histologically in the spleen, lung, nasal cavity, and kidney for both single and repeated doses of 10 mg Ga /Kg of mice over 13 days. Our results strongly suggest that GaPP and Ga(NO3)3 in combination have excellent synergism and potential to be developed as a novel therapy for infections with S. aureus.


Assuntos
Gálio , Staphylococcus aureus Resistente à Meticilina , Animais , Camundongos , Protoporfirinas/farmacologia , Protoporfirinas/metabolismo , Staphylococcus aureus , Distribuição Tecidual , Antibacterianos/farmacologia , Gálio/farmacologia , Heme/metabolismo , Ferro/metabolismo , Testes de Sensibilidade Microbiana
6.
J Mater Chem B ; 11(17): 3941-3950, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-37067358

RESUMO

Gallium (Ga) is a low melting point metal in the liquid state in the biological environment which presents a unique combination of fluidity, softness, and metallic electrical and thermal properties. In this work, liquid Ga is proposed as a biocompatible electrode material for cell culture by electro-stimulation since the cytotoxicity of Ga is generally considered low and some Ga compounds have been reported to exhibit anti-bacterial and anti-inflammatory activities. Complementarily, polydopamine (PDA) was coated on liquid Ga to increase the attachment capability of cells on the liquid Ga electrode and provide enhanced biocompatibility. The liquid Ga layer could be readily painted at room temperature on a solid inert substrate, followed by the formation of a nanoscale PDA coating layer resulting in a conformable and biocompatible composite electrode. The PDA layer was shown to coordinate with Ga3+, which is sourced from liquid Ga, providing electrical conductivity in the cell culture medium. The PDA-Ga3+ composite acted as a conductive substrate for advanced electro-stimulation for cell culture methods of representative animal fibroblasts. The cell proliferation was observed to increase by ∼143% as compared to a standard glass coverslip at a low potential of 0.1 V of direct coupling stimulation. This novel PDA-Ga3+ composite has potential applications in cell culture and regenerative medicine.


Assuntos
Gálio , Polímeros , Animais , Polímeros/farmacologia , Polímeros/química , Materiais Biocompatíveis/farmacologia , Gálio/farmacologia , Técnicas de Cultura de Células
7.
Nanoscale ; 15(9): 4457-4468, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36752324

RESUMO

Precision medicine urges the development of theranostics which can efficiently integrate precise diagnosis and effective therapy. In this study, a facile synthesis of Ir/Gd bimetallic oxide nanotheranostics (termed BSA@Gd2O3/IrO2 NPs) with good biocompatibility was demonstrated using a biomineralization method where bovine serum albumin (BSA) served as a versatile template. BSA@Gd2O3/IrO2 NPs exhibited high longitudinal relaxivity (5.2 mM-1 s-1) and X-ray absorption capability (14.5 Hu mM-1), illustrating them to be a good contrast agent for magnetic resonance (MR) and computed tomography (CT) dual-modal imaging. Moreover, BSA@Gd2O3/IrO2 NPs can act as not only a photothermal conversion agent with ultrahigh efficiency (66.7%) as well as a good photosensitizer, but also an effective catalase to decompose endogenous H2O2 to produce O2, thus relieving hypoxia and enhancing the phototherapeutic effect. Both in vitro and in vivo experiments demonstrated the high effectiveness of BSA@Gd2O3/IrO2 NPs in MR/CT dual-modal imaging and photothermal and photodynamic synergistic tumor treatments. This work sheds new light on the development of versatile nanotheranostic systems using mild and robust biomineralization methods.


Assuntos
Nanopartículas , Soroalbumina Bovina , Linhagem Celular Tumoral , Peróxido de Hidrogênio , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Óxidos , Fototerapia/métodos , Nanomedicina Teranóstica/métodos , Tomografia Computadorizada por Raios X , Gálio , Irídio
8.
Bioorg Chem ; 129: 106177, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36183563

RESUMO

Two new trimethoxyl A2B triaryl corroles 10-(2,4,6-trimethoxyphenyl)-5,15-bis(pentafluorophenyl)- corrole (1) and 10-(3,4,5-trimethoxyphenyl)-5,15-bis(pentafluorophenyl)-corrole (2) and their gallium(III) and phosphorus(V) (1-Ga, 1-P, 2-Ga and 2-P) complexes had been prepared and well characterized by UV-vis, NMR and HR-MS. Among all compounds, 2-Ga, 1-P and 2-P showed excellent in vivo photodynamic activity against the MDA-MB-231, A549, Hela and HepG2 cell lines upon light irradiation at 625 nm. And 2-P even exhibited higher phototoxicity than the clinical photosensitizer temoporfin. Also, 2-P exhibited the highest singlet oxygen quantum yield and photostability. The preliminary investigation revealed that 2-P could be rapidly absorbed by tumor cells and mainly located in the cytoplasm. After photodynamic therapy (PDT) treatment with 2-P, mitochondrial membrane potential destruction, intracellular ROS level increasing and nuclear fragmentation of cancer cells could be observed. Cell cycle analysis demonstrated that the 2-P PDT may cause tumor cell arrest at sub-G1 stage and induce early and late apoptosis of cells. These results suggest that 2-P is a promising candidate as a photosensitizer for photodynamic therapy.


Assuntos
Gálio , Fotoquimioterapia , Humanos , Gálio/farmacologia , Gálio/química , Fármacos Fotossensibilizantes/farmacologia , Fósforo/farmacologia , Linhagem Celular Tumoral
9.
Nano Lett ; 22(20): 8174-8180, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36223431

RESUMO

A wafer-thin chip-scale portable spectrometer suitable for wearable applications based on a reconstructive algorithm was demonstrated. A total of 16 spectral encoders that simultaneously functioned as photodetectors were monolithically integrated on a chip area of 0.16 mm2 by applying local strain engineering in compressively strained InGaN/GaN multiple quantum well heterostructures. The built-in GaN pn junction enabled a direct photocurrent measurement. A non-negative least-squares (NNLS) algorithm with total-variation regularization and a choice of a proper kernel function was shown to deliver a decent spectral reconstruction performance in the wavelength range of 400-645 nm. The accuracies of spectral peak positions and intensity ratios between peaks were found to be 0.97% and 10.4%, respectively. No external optics, such as collimation optics and apertures, were used, enabled by angle-insensitive light-harvesting structures, including an array of cone-shaped backreflectors fabricated on the underside of the sapphire substrate.


Assuntos
Gálio , Gálio/química , Semicondutores , Iluminação , Análise de Falha de Equipamento , Desenho de Equipamento , Óxido de Alumínio/química
10.
Sci Rep ; 12(1): 16007, 2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-36163387

RESUMO

Bioleaching is an actual economical alternative to treat residues, which allows, depending on the chosen strategy, two possible outcomes: (1) a leachate enriched with target metals, or (2) a residue enriched in target metals through the leaching of interfering components (IC). This work aimed to study the metals released by bioprocessing the Panasqueira mine tailings, as a strategy to increase critical metals' relative concentration in residues. Biostimulation of the local microbiota was compared to a bioaugmentation approach using the autochthonous Diaphorobacter polyhydroxybutyrativorans strain B2A2W2. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was selected to study the metals released in the leachate through multi-element external standards. A new data treatment method was developed to use a preliminary sweep of intensities to quantify the non-initial target metals concentration in the leachate, based on preliminary ICP-MS intensity measurements. The results demonstrated that biostimulation was an efficient bioleaching strategy for the IC silicon, aluminium, magnesium, selenium, manganese, zinc, iron, and copper, by decreasing concentration, resulting in a relative increase in the gallium and yttrium (10x) levels in the treated residue. The strategy followed to quantify a large number of elements with ICP-MS using a reduced number of data points for calibration proved valid and speeded up the analytical process.


Assuntos
Gálio , Selênio , Alumínio , Calibragem , Cobre/análise , Ferro , Magnésio , Manganês , Silício , Ítrio , Zinco/análise
11.
Sensors (Basel) ; 22(15)2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35957376

RESUMO

Several detectors have been developed to measure radiation doses during radiotherapy. However, most detectors are not flexible. Consequently, the airgaps between the patient surface and detector could reduce the measurement accuracy. Thus, this study proposes a dose measurement system based on a flexible copper indium gallium selenide (CIGS) solar cell. Our system comprises a customized CIGS solar cell (with a size 10 × 10 cm2 and thickness 0.33 mm), voltage amplifier, data acquisition module, and laptop with in-house software. In the study, the dosimetric characteristics, such as dose linearity, dose rate independence, energy independence, and field size output, of the dose measurement system in therapeutic X-ray radiation were quantified. For dose linearity, the slope of the linear fitted curve and the R-square value were 1.00 and 0.9999, respectively. The differences in the measured signals according to changes in the dose rates and photon energies were <2% and <3%, respectively. The field size output measured using our system exhibited a substantial increase as the field size increased, contrary to that measured using the ion chamber/film. Our findings demonstrate that our system has good dosimetric characteristics as a flexible in vivo dosimeter. Furthermore, the size and shape of the solar cell can be easily customized, which is an advantage over other flexible dosimeters based on an a-Si solar cell.


Assuntos
Cobre , Índio , Gálio , Humanos , Doses de Radiação , Radiometria , Selênio , Raios X
12.
Seizure ; 101: 67-74, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35932526

RESUMO

PURPOSE: We previously reported seizure and EEG outcomes of the ESTEL study (Electrical Stimulation of Thalamus for Epilepsy of Lennox-Gastaut phenotype). To assess potential cognitive and behavioral changes during chronic, duty-cycle stimulation of bilateral thalamic centromedian nucleus, we compared standardized cognitive and behavioral measurements, as well as caregiver assessments of disability/severity, before implantation and after 3-months stimulation. METHODS: Twenty patients with LGS (17-37 years;13 females) were studied; one participant was not randomized due to DBS device removal, with outcomes of 19 remaining participants reported here. Cognitive and behavioral measurements were performed at baseline (i.e., before DBS implantation), at the end of the blinded stimulation phase, and at study exit. Instruments measured cognition (NIH toolbox cognitive battery, NIHTB-CB), adaptive skills (ABAS-3), epilepsy severity (GASE) and disability (GAD), quality of life (QOLIE-31), and depression (PHQ-9). Changes in scores after 3-months of stimulation relative to baseline were explored using Wilcoxon matched-pairs signed rank tests. RESULTS: After 3-months of stimulation, caregiver-reported epilepsy severity (GASE) and disability (GAD) improved (p<0.05). No other instrument showed a significant change from baseline. Measurements that required direct participant involvement, rather than caregivers, was completed by only a subset of higher-functioning individuals (NIHTB-CB, n = 13; QOLIE-31, n = 3; and PHQ-9, n = 6). In addition to cognitive impairments, behavioral and physical limitations were common obstacles to instrument completion. Standardized scores were hindered by 'floor effects'; however, raw scores better reflected clinical impressions of participants' functioning and were more sensitive to caregiver-reported changes following treatment. CONCLUSION: DBS treatment is associated with reduced epilepsy severity and disability in young adults with LGS. Performing cognitive and behavioral outcome measurement in patients with cognitive impairment is challenging but possible and requires careful selection of instruments and modifications of score interpretation to avoid floor effects.


Assuntos
Estimulação Encefálica Profunda , Epilepsia , Síndrome de Lennox-Gastaut , Adolescente , Adulto , Cognição , Epilepsia/terapia , Feminino , Gálio , Humanos , Síndrome de Lennox-Gastaut/terapia , Masculino , Qualidade de Vida , Selênio , Adulto Jovem
13.
Chempluschem ; 87(7): e202200188, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35856654

RESUMO

This work reports the preparation and characterization of an A2 B corrole 5,15-bis(perfluorophenyl)-10-(4-carboxyphenyl)corrole and its gallium(III) and phosphorus(V) complexes. Their in-vitro photodynamic anticancer activities against A549, MDA-MB-231, B16, HepG2, and Hela cell lines were also investigated. Among three compounds, phosphorus(V) complexexhibits the best photostability, highest fluorescence quantum yields (ΦF =0.138), and the highest singlet-oxygen quantum yields (ΦΔ =0.87). Also, the phosphorus(V) complex exhibits the best photodynamic antitumor activity against MDA-MB-231 cells with a low IC50 (0.08 µM) upon light irradiation at 625±2 nm, which is much lower than commercial PDT drug Temoporfin (0.1 µM) at the same conditions. The cellular localization assay confirmed that the phosphorus(V) complexis mainly distributed in the cytoplasm and have a good ability to produce reactive oxygen species (ROS) under light illumination, which would further cause oxidative damage to tumor cells and finally result in the apoptosis. After PDT treatment, phosphorus(V) complex may cause tumor cell arrest at the G2/M stage. The preliminary results showed phosphorus(V) corrole complex is a good candidate for photodynamic therapy (PDT) of tumors.


Assuntos
Gálio , Fármacos Fotossensibilizantes , Linhagem Celular Tumoral , Gálio/farmacologia , Células HeLa , Humanos , Fósforo , Fármacos Fotossensibilizantes/farmacologia , Porfirinas
14.
Biomed Eng Online ; 21(1): 38, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715781

RESUMO

BACKGROUND: Although the powerful clinical effects of radiofrequency and microwave ablation have been established, such ablation is associated with several limitations, including a small ablation size, a long ablation time, the few treatment positioning, and biosafety risks. To overcome these limitations, biosafe and efficient magnetic ablation was achieved in this study by using biocompatible liquid gallium as an ablation medium and a contrast medium for imaging. RESULTS: Magnetic fields with a frequency (f) lower than 200 kHz and an amplitude (H) × f value lower than 5.0 × 109 Am-1 s-1 were generated using the proposed method. These fields could generate an ablation size of 3 cm in rat liver lobes under a temperature of approximately 300 °C and a time of 20 s. The results of this study indicate that biomedical gallium can be used as a contrast medium for the positioning of gallium injections and the evaluation of ablated tissue around a target site. Liquid gallium can be used as an ablation medium and imaging contrast medium because of its stable retention in normal tissue for at least 3 days. Besides, the high anticancer potential of gallium ions was inferred from the self-degradation of 100 µL of liquid gallium after around 21 days of immersion in acidic solutions. CONCLUSIONS: The rapid wireless ablation of large or multiple lesions was achieved through the simple multi-injection of liquid gallium. This approach can replace the currently favoured procedure involving the use of multiple ablation probes, which is associated with limited benefits and several side effects. METHODS: Magnetic ablation was confirmed to be highly efficient by the consistent results obtained in the simulation and in vitro tests of gallium and iron oxide as well as the electromagnetic specifics and thermotherapy performance comparison detailed in this study Ultrasound imaging, X-ray imaging, and magnetic resonance imaging were found to be compatible with the proposed magnetic ablation method. Self-degradation analysis was conducted by mixing liquid gallium in acidic solutions with a pH of approximately 5-7 (to imitate a tumour-containing microenvironment). X-ray diffraction was used to identify the gallium oxides produced by degraded gallium ions.


Assuntos
Técnicas de Ablação , Ablação por Cateter , Gálio , Animais , Gálio/farmacologia , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Ratos , Ultrassonografia
15.
J Am Chem Soc ; 144(15): 6779-6790, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35293736

RESUMO

This report presents nanoparticles composed of a liquid gallium core with a reduced graphene oxide (RGO) shell (Ga@RGO) of tunable thickness. The particles are produced by a simple, one-pot nanoprobe sonication method. The high near-infrared absorption of RGO results in a photothermal energy conversion of light to heat of 42.4%. This efficient photothermal conversion, combined with the large intrinsic thermal expansion coefficient of liquid gallium, allows the particles to be used for photoacoustic imaging, that is, conversion of light into vibrations that are useful for imaging. The Ga@RGO results in fivefold and twofold enhancement in photoacoustic signals compared with bare gallium nanoparticles and gold nanorods (a commonly used photoacoustic contrast agent), respectively. A theoretical model further reveals the intrinsic factors that affect the photothermal and photoacoustic performance of Ga@RGO. These core-shell Ga@RGO nanoparticles not only can serve as photoacoustic imaging contrast agents but also pave a new way to rationally design liquid metal-based nanomaterials with specific multi-functionality for biomedical applications.


Assuntos
Gálio , Grafite , Nanopartículas , Técnicas Fotoacústicas , Meios de Contraste , Ouro , Técnicas Fotoacústicas/métodos , Fototerapia/métodos
16.
ACS Appl Bio Mater ; 5(2): 779-788, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-35061367

RESUMO

Liquid metals (LMs), typically gallium and its alloys, are emerging functional materials for nanotechnology, yet the applications of LM nanoparticles (LMNPs) in biomedical areas are still in their infancy. This predicament occurs primarily because LMNPs are generally synthesized with inadequately protected surfaces rendering rapid uncontrollable oxidation in physiological conditions. Herein, we show that depositing a polymeric supra-nanoparticle shell on LMNPs through sonochemical assembly can alleviate their oxidation kinetics and maintain their designed functionalities, even during hyperthermia processing. The LMNPs with polymer encapsulation promise to be excellent candidate materials for stable, biocompatible, and reusable photothermal converters under near-infrared (NIR) laser irradiation, showing doubled photothermal conversion efficiency compared with unprotected ones. Besides, they are employed, alone or synergistically with a hydrogel matrix, as potent photothermal bactericidal agents, both in vitro and in vivo. Specifically, the LMNPs-embedded agarose hydrogel allows the disinfection and concurrently accelerated healing of full-thickness skin wounds. The nanoshell-enabled heat resistance of LMNPs is expected to broaden the horizons of LM-based nano/biomedicine, potentially against superbugs and cancer.


Assuntos
Gálio , Hipertermia Induzida , Nanoconchas , Hidrogéis/farmacologia , Polímeros/farmacologia
17.
Lasers Med Sci ; 37(2): 1167-1174, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34227042

RESUMO

The purposes of this study were (1) to investigate the direct effect of an Er,Cr:YSGG laser on human apical papilla cell (APC) proliferation and mineralization and (2) to examine the effect of Er,Cr:YSGG laser, when applied to an ex vivo immature tooth model, on APC attachment. An Er,Cr:YSGG laser at various power outputs (0.1, 0.5, and 1 W) was used at different positions (2, 5, or 8 mm from the cells) to irradiate cultured APCs. APC proliferation and mineralization were assessed at various intervals. For the cell attachment evaluation, ex vivo tooth models containing dentin samples were irrigated with either EDTA or normal saline solution (NSS) and supplemented with laser activation. Fibronectin-positive-staining cells were counted and analyzed. The number of APCs was significantly greater when power outputs of 0.1 W and 0.5 W were used than when 1 W was used (P < 0.05). The close contact of laser application, at 2 and 5 mm, exerted a negative effect on cell proliferation at 24 and 48 h. The application at 8 mm did not show the deterioration effect. APC mineralization was reduced after laser irradiation, regardless of the power and the tip positioning, at 21 days. APC attachment in all laser-activated groups was significantly greater than in the groups without laser. The use of Er,Cr:YSGG laser significantly promoted APC attachment on the root canal dentin.


Assuntos
Gálio , Lasers de Estado Sólido , Cromo , Érbio , Humanos , Lasers de Estado Sólido/uso terapêutico , Escândio , Ítrio
18.
Diagn Microbiol Infect Dis ; 102(2): 115569, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34775292

RESUMO

Iron uptake and metabolism have become attractive targets for the development of new antibacterial drugs. In this scenario, the FDA-approved iron mimetic metal gallium [Ga (III)] has been successfully researched as an antimicrobial drug. Ga (III) inhibits microbial growth by disrupting ferric iron-dependent metabolic pathways. In this study, we revealed that gallium nitrate III (GaN) inhibits the growth of a collection of twenty polymyxin-resistant Klebsiella pneumoniae strains at concentrations ranging from 2 to 16µg/mL, using a medium, on which the low iron content and the presence of human serum better mimic the in vivo environment. GaN was also successful in protecting Caenorhabditis elegans from polymyxin-resistant K. pneumoniae strains lethal infection, with survival rates of >75%. GaN also exhibited synergism with polymyxin B, suggesting that a polymyxin B-GaN combination holds promise like as one alternative therapy for infections caused by resistant polymyxin B K. pneumoniae strains.


Assuntos
Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Gálio/farmacologia , Gálio/uso terapêutico , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Variação Genética , Genótipo , Humanos , Testes de Sensibilidade Microbiana
19.
Dalton Trans ; 50(45): 16819-16828, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34775504

RESUMO

Environmentally friendly synthesis of Cu(In,Ga)Se2 (CIGS) nanoparticles (NPs) is pivotal for producing sustainable photocatalytic compounds to be applied in the remediation of contaminants of emerging concern from water. To this end, we herein report an aqueous synthesis of CIGS NPs, followed by annealing, to give access to phase-pure CIGS crystals with chalcopyrite structure and no signs of secondary phases. Morphological and compositional characterization revealed NPs with an average size of 10-35 nm and uniform distribution of Cu, In, Ga, and Se elements. In addition, the first aqueous large-scale synthesis of CIGS NPs is developed by up-scaling the synthesis procedure, resulting in 5 g of highly crystalline nanoparticles exhibiting an ideal optical band gap of 1.14 eV. The as-synthesized NPs proved the ability to remove 71 and 83% of a contaminant of emerging concern, ciprofloxacin (CIP), under ultraviolet (UV) and visible (Vis) radiations, respectively.


Assuntos
Ciprofloxacina/química , Cobre/química , Gálio/química , Índio/química , Nanopartículas Metálicas/química , Selênio/química , Catálise , Microscopia Eletrônica de Transmissão e Varredura , Processos Fotoquímicos , Termogravimetria , Água/química , Difração de Raios X
20.
Sci Rep ; 11(1): 20817, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34675308

RESUMO

T2* relaxation is an intrinsic magnetic resonance imaging (MRI) parameter that is sensitive to local magnetic field inhomogeneities created by the deposition of endogenous paramagnetic material (e.g. iron). Recent studies suggest that T2* mapping is sensitive to iron oxidation state. In this study, we evaluate the spin state-dependence of T2* relaxation using T2* mapping. We experimentally tested this physical principle using a series of phantom experiments showing that T2* relaxation times are directly proportional to the spin magnetic moment of different transition metals along with their associated magnetic susceptibility. We previously showed that T2* relaxation time can detect the oxidation of Fe2+. In this paper, we demonstrate that T2* relaxation times are significantly longer for the diamagnetic, d10 metal Ga3+, compared to the paramagnetic, d5 metal Fe3+. We also show in a cell culture model that cells supplemented with Ga3+ (S = 0) have a significantly longer relaxation time compared to cells supplemented with Fe3+ (S = 5/2). These data support the hypothesis that dipole-dipole interactions between protons and electrons are driven by the strength of the electron spin magnetic moment in the surrounding environment giving rise to T2* relaxation.


Assuntos
Imageamento por Ressonância Magnética , Teoria Quântica , Cátions/química , Elétrons , Gálio/química , Peróxido de Hidrogênio/química , Ferro/química , Prótons
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