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1.
J Chem Phys ; 160(10)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38456529

RESUMO

We propose a quantum tomography (QT) approach to retrieve the temporally evolving reduced density matrix in electronic state basis, where the populations and coherence between the ground state and excited state are reconstructed from the ultrafast electron diffraction signal. In order to showcase the capability of the proposed QT approach, we simulate the nuclear wavepacket dynamics and ultrafast electron diffraction of photoexcited pyrrole molecules using the ab initio quantum chemical CASSCF method. From the simulated time-resolved diffraction data, we retrieve the evolving density matrix in a crude diabatic representation basis and reveal the symmetry of the excited pyrrole wavepacket. Our QT approach opens the route to make a quantum version of "molecular movie" that covers the electronic degree of freedom and equips ultrafast electron diffraction with the power to reveal the coherence between electronic states, relaxation, and dynamics of population transfer.

2.
Small ; 20(13): e2306068, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37963834

RESUMO

Optoelectronic synapses are currently drawing significant attention as fundamental building blocks of neuromorphic computing to mimic brain functions. In this study, a two-terminal synaptic device based on a doped PdSe2 flake is proposed to imitate the key neural functions in an optical pathway. Due to the wavelength-dependent desorption of oxygen clusters near the intrinsic selenide vacancy defects, the doped PdSe2 photodetector achieves a high negative photoresponsivity of -7.8 × 103 A W-1 at 473 nm and a positive photoresponsivity of 181 A W-1 at 1064 nm. This wavelength-selective bi-direction photoresponse endows an all-optical pathway to imitate the fundamental functions of artificial synapses on a device level, such as psychological learning and forgetting capability, as well as dynamic logic functions. The underpinning photoresponse is further demonstrated on a flexible platform, providing a viable technology for neuromorphic computing in wearable electronics. Furthermore, the p-type doping results in an effective increase of the channel's electrical conductivity and a significant reduction in power consumption. Such low-power-consuming optical synapses with simple device architecture and low-dimensional features demonstrate tremendous promise for building multifunctional artificial neuromorphic systems in the future.

3.
Mar Drugs ; 21(10)2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37888439

RESUMO

A systematic chemical investigation of the deep-sea-derived fungus Aspergillus versicolor 170217 resulted in the isolation of six new (1-6) and 45 known (7-51) compounds. The structures of the new compounds were established on the basis of exhaustive analysis of their spectroscopic data and theoretical-statistical approaches including GIAO-NMR, TDDFT-ECD/ORD calculations, DP4+ probability analysis, and biogenetic consideration. Citriquinolinones A (1) and B (2) feature a unique isoquinolinone-embedded citrinin scaffold, representing the first exemplars of a citrinin-isoquinolinone hybrid. Dicitrinones K-L (3-4) are two new dimeric citrinin analogues with a rare CH-CH3 bridge. Biologically, frangula-emodin (32) and diorcinol (17) displayed remarkable anti-food allergic activity with IC50 values of 7.9 ± 3.0 µM and 13.4 ± 1.2 µM, respectively, while diorcinol (17) and penicitrinol A (20) exhibited weak inhibitory activity against Vibrio parahemolyticus, with MIC values ranging from 128 to 256 µM.


Assuntos
Citrinina , Citrinina/química , Aspergillus/química , Fungos , Espectroscopia de Ressonância Magnética , Estrutura Molecular
4.
Int J Nanomedicine ; 18: 5871-5890, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37873552

RESUMO

Background: Hyaluronic acid (HA) is a popular biological material for osteoarthritis (OA) treatment. Pioglitazone, a PPAR-γ agonist, has been found to inhibit OA, but its use is limited because achieving the desired local drug concentration after administration is challenging. Purpose: Herein, we constructed HA-based cartilage-targeted nanomicelles (C-HA-DOs) to deliver pioglitazone in a sustained manner and evaluated their efficacy in vitro and in vivo. Methods: C-HA-DOs were chemically synthesized with HA and the WYRGRL peptide and dodecylamine. The products were characterized by FT-IR, 1H NMR, zeta potential and TEM. The drug loading rate and cumulative, sustained drug release from Pio@C-HA-DOs were determined, and their biocompatibility and effect on oxidative stress in chondrocytes were evaluated. The uptake of C-HA-DOs by chondrocytes and their effect on OA-related genes were examined in vitro. The nanomicelle distribution in the joint cavity was observed by in vivo small animal fluorescence imaging (IVIS). The therapeutic effects of C-HA-DOs and Pio@C-HA-DOs in OA rats were analysed histologically. Results: The C-HA-DOs had a particle size of 198.4±2.431 nm, a surface charge of -8.290±0.308 mV, and a critical micelle concentration of 25.66 mg/Land were stable in solution. The cumulative drug release from the Pio@C-HA-DOs was approximately 40% at pH 7.4 over 24 hours and approximately 50% at pH 6.4 over 4 hours. Chondrocytes rapidly take up C-HA-DOs, and the uptake efficiency is higher under oxidative stress. In chondrocytes, C-HA-DOs, and Pio@C-HA-DOs inhibited H2O2-induced death, reduced intracellular ROS levels, and restored the mitochondrial membrane potential. The IVIS images confirmed that the micelles target cartilage. Pio@C-HA-DOs reduced the degradation of collagen II and proteoglycans by inhibiting the expression of MMP and ADAMTS, ultimately delaying OA progression in vitro and in vivo. Conclusion: Herein, C-HA-DOs provided targeted drug delivery to articular cartilage and improved the role of pioglitazone in the treatment of OA.


Assuntos
Cartilagem Articular , Osteoartrite , Ratos , Animais , Ácido Hialurônico/química , Pioglitazona/farmacologia , Pioglitazona/metabolismo , Pioglitazona/uso terapêutico , Peróxido de Hidrogênio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Osteoartrite/patologia , Condrócitos
5.
Nano Lett ; 23(20): 9522-9528, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37823381

RESUMO

Constructing high-quality homojunctions plays a pivotal role for the advancement of two-dimensional transition metal sulfide (TMDC) based optoelectronic devices. Here, a lateral PdSe2 p-i-n homojunction is constructed by electrostatic doping. Electrical measurements reveal that the homojunction diode exhibits a strong rectifying characteristic with a rectification ratio exceeding 104 and an ideality factor approaching 1. When functioning in photovoltaic mode, the device achieves a high responsivity of 1.1 A/W under 1064 nm illumination, with a specific detectivity of 1.3 × 1011 Jones and a high linearity of 45 dB. Benefiting from the lateral p-i-n structure, the junction capacitance is significantly reduced, and an ultrafast response (3/6 µs) is obtained. Additionally, the photodiode has the capability of polarization distinction due to the unique in-plane anisotropic structure of PdSe2, exhibiting a dichroic ratio of 1.6 at a 1064 nm wavelength. This high-performance polarization-sensitive near-infrared photodetector exhibits great potential in the next-generation optoelectronic applications.

6.
Prep Biochem Biotechnol ; 53(1): 76-80, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35196461

RESUMO

Preparation of sufficient mouse Leydig cells (LCs) with high purity is a prerequisite for investigations of the biological/pathological functions of LCs in mouse models. Density gradient centrifugation based on discontinuous Percoll gradients is an effective method (defined as regular method) for LC isolation. In this study, we developed two modified methods for LC isolation and compared their performance with that of the regular method. Modified method 1 integrated the crude LCs into the 50% Percoll solution before centrifugation. Modified method 2 sequentially used 50 and 60% Percoll solutions to isolate LCs. The purity of LCs was approximately 88.4, 91.3, and 79.7% derived from the regular, modified 1, and modified 2 methods, respectively. The yields of LCs in the same respective order were approximately 1.7 × 105, 3.9 × 105, and 11.9 × 105 cells per 108 interstitial cells input. Modified method 1 attained higher purity and yields than those of the regular method. Although the purity of LCs was relatively low for modified method 2, it could be used before further purification by, for example, fluorescence-activated or magnetic-activated cell sorting, owing to its simplicity and high yields. Therefore, our study provided alternative methods to facilitate LC isolation in mice.


Assuntos
Células Intersticiais do Testículo , Masculino , Camundongos , Animais , Centrifugação com Gradiente de Concentração/métodos , Separação Celular/métodos , Centrifugação
7.
Chem Biodivers ; 19(12): e202200963, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36436828

RESUMO

The Cladosporium fungi, one of the largest genera of dematiaceous hyphomycetes, could produce various bioactive secondary metabolites. From the AcOEt-soluble extract of Cladosporium oxysporum 170103, three new secopatulolides (1-3) and thirteen known compounds (4-16) were obtained. Their structures were established by detailed analysis of the NMR and HR-ESI-MS data. All sixteen compounds were tested for antibacterial activity against Vibrio parahemolyticus, ergosterol (10) presented moderate effect with the minimum inhibitory concentration (MIC) of 32 µM. It can destruct the membrane integrity of Vibrio parahemolyticus to change the cell shape.


Assuntos
Antibacterianos , Cladosporium , Cladosporium/química , Estrutura Molecular , Antibacterianos/farmacologia , Antibacterianos/química , Fungos
8.
Asian J Androl ; 24(1): 102-108, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34100389

RESUMO

Klinefelter syndrome (KS) is one of the most frequent genetic abnormalities and the leading genetic cause of nonobstructive azoospermia. The breeding and study of KS mouse models are essential to advancing our knowledge of the underlying pathological mechanism. Karyotyping and fluorescence in situ hybridization are reliable methods for identifying chromosomal contents. However, technical issues associated with these methods can decrease the efficiency of breeding KS mouse models and limit studies that require rapid identification of target mice. To overcome these limitations, we developed three polymerase chain reaction-based assays to measure specific genetic information, including presence or absence of the sex determining region of chromosome Y (Sry), copy number of amelogenin, X-linked (Amelx), and inactive X specific transcripts (Xist) levels. Through a combined analysis of the assay results, we can infer the karyotype of target mice. We confirmed the utility of our assays with the successful generation of KS mouse models. Our assays are rapid, inexpensive, high capacity, easy to perform, and only require small sample amounts. Therefore, they facilitate the breeding and study of KS mouse models and help advance our knowledge of the pathological mechanism underlying KS.


Assuntos
Azoospermia , Síndrome de Klinefelter , Animais , Hibridização in Situ Fluorescente , Cariotipagem , Síndrome de Klinefelter/genética , Camundongos , Reação em Cadeia da Polimerase
9.
Front Bioeng Biotechnol ; 9: 771153, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869286

RESUMO

Bone is a preferred site for both primary and metastasis tumors. Current diagnosis of osteopathia typically relies on noninvasive skeleton radiography technology. However, due to the limited resolution of ionizing radiation, accurate diagnosis and effective identification impairment areas are still lacking. Near-infrared (NIR) bioimaging, especially in the NIR-II (1000-1700 nm) regions, can provide high sensitivity and spatiotemporal resolution bioimaging compared to the conventional radiography. Thus, NIR bioimaging affords intraoperative visualization and imaging-guided surgery, aiming to overcome challenges associated with theranostics of osteopathia and bone tumors. The present review aimed to summarize the latest evidence on the use of NIR probes for the targeting bone imaging. We further highlight the recent advances in bone photoX (X presents thermal, dynamic, and immuno) therapy through NIR probes, in particular combination with other customized therapeutic agents could provide high-efficiency treatment for bone tumors.

10.
Nat Commun ; 12(1): 1825, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33758200

RESUMO

Van der Waals heterostructures (vdWHs) have attracted tremendous interest owing to the ability to assemble diverse building blocks without the constraints of lattice matching and processing compatibility. However, once assembled, the fabricated vdWHs can hardly be separated into individual building blocks for further manipulation, mainly due to technical difficulties in the disassembling process. Here, we show a method to disassemble the as-fabricated vdWHs into individual building blocks, which can be further reassembled into new vdWHs with different device functionalities. With this technique, we demonstrate reconfigurable transistors from n-type to p-type and back-gate to dual-gate structures through re-stacking. Furthermore, reconfigurable device behaviors from floating gate memory to Schottky diode and reconfigurable anisotropic Raman behaviors have been obtained through layer re-sequencing and re-twisting, respectively. Our results could lead to a reverse engineering concept of disassembled vdWHs electronics in parallel with state-of-the-art vdWHs electronics, offering a general method for multi-functional pluggable electronics and optoelectronics with limited material building blocks.

11.
Inflammation ; 44(3): 846-858, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33140204

RESUMO

Periodontitis is a chronic inflammatory disease induced by Porphyromonas gingivalis (P. gingivalis) and other pathogens. P. gingivalis release various virulence factors including lipopolysaccharide (LPS). However, whether P. gingivalis-LPS inducing pyroptosis in human gingival fibroblasts (HGFs) remains unknown. In present study, P. gingivalis-LPS decreased the membrane integrity of HGFs, and pyroptosis-associated cytokines were upregulated at the mRNA level. In addition, pyroptosis proteins were highly expressed in gingival tissues of periodontitis. P. gingivalis-LPS induced gingivitis in the rat model, and the expression level of pyroptosis-associated proteins increased. Together, P. gingivalis-LPS can activate the pyroptosis reaction, which may be a pro-pyroptosis status in a relative low concentration.


Assuntos
Fibroblastos/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Gengivite/induzido quimicamente , Lipopolissacarídeos/toxicidade , Porphyromonas gingivalis/metabolismo , Piroptose/efeitos dos fármacos , Animais , Caspase 1/metabolismo , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Gengiva/metabolismo , Gengiva/patologia , Gengivite/metabolismo , Gengivite/patologia , Humanos , Lipopolissacarídeos/isolamento & purificação , Masculino , Ratos Sprague-Dawley , Transdução de Sinais , Regulação para Cima
12.
Front Genet ; 12: 776807, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35154243

RESUMO

Primary Coenzyme Q10 Deficiency-7 (COQ10D7) is a rare mitochondrial disorder caused by pathogenic COQ4 variants. In this review, we discuss the correlation of COQ4 genotypes, particularly the East Asian-specific c.370G > A variant, with the clinical presentations and therapeutic effectiveness of coenzyme Q10 supplementation from an exon-dependent perspective. Pathogenic COQ4 variants in exons 1-4 are associated with less life-threating presentations, late onset, responsiveness to CoQ10 therapy, and a relatively long lifespan. In contrast, pathogenic COQ4 variants in exons 5-7 are associated with early onset, unresponsiveness to CoQ10 therapy, and early death and are more fatal. Patients with the East Asian-specific c.370G > A variant displays intermediate disease severity with multi-systemic dysfunction, which is between that of the patients with variants in exons 1-4 and 5-7. The mechanism underlying this exon-dependent genotype-phenotype correlation may be associated with the structure and function of COQ4. Sex is shown unlikely to be associated with disease severity. While point-of-care high-throughput sequencing would be useful for the rapid diagnosis of pathogenic COQ4 variants, whereas biochemical analyses of the characteristic impairments in CoQ10 biosynthesis and mitochondrial respiratory chain activity, as well as the phenotypic rescue of the CoQ10 treatment, are necessary to confirm the pathogenicity of suspicious variants. In addition to CoQ10 derivatives, targeted drugs and gene therapy could be useful treatments for COQ10D7 depending on the in-depth functional investigations and the development of gene editing technologies. This review provides a fundamental reference for the sub-classification of COQ10D7 and aim to advance our knowledge of the pathogenesis, clinical diagnosis, and prognosis of this disease and possible interventions.

13.
Nat Commun ; 11(1): 4266, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32848133

RESUMO

Two-dimensional (2D) Ruddlesden-Popper perovskites are currently drawing significant attention as highly-stable photoactive materials for optoelectronic applications. However, the insulating nature of organic ammonium layers in 2D perovskites results in poor charge transport and limited performance. Here, we demonstrate that Al2O3/2D perovskite heterostructure can be utilized as photoactive dielectric for high-performance MoS2 phototransistors. The type-II band alignment in 2D perovskites facilitates effective spatial separation of photo-generated carriers, thus achieving ultrahigh photoresponsivity of >108 A/W at 457 nm and >106 A/W at 1064 nm. Meanwhile, the hysteresis loops induced by ionic migration in perovskite and charge trapping in Al2O3 can neutralize with each other, leading to low-voltage phototransistors with negligible hysteresis and improved bias stress stability. More importantly, the recombination of photo-generated carriers in 2D perovskites depends on the external biasing field. With an appropriate gate bias, the devices exhibit wavelength-dependent constant photoresponsivity of 103-108 A/W regardless of incident light intensity.

14.
ACS Appl Mater Interfaces ; 12(11): 12383-12394, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32091195

RESUMO

Drug-induced liver injury (DILI) is a widespread clinical problem. The pathophysiological mechanisms of DILI are complicated, and the traditional diagnostic methods for DILI have their limitations. Owing to its convenient operation, high sensitivity, and high specificity, luminescent sensing and imaging as an indispensable tool in biological research and clinical trials may provide an important means for DILI study. Herein, we report the rational design and preparation of a near-infrared dual-phosphorescent polymeric probe (P-ONOO) for exploring the DILI via specific imaging of peroxynitrite (ONOO-) elevation in vivo, which was one of early markers of DILI and very difficult to be detected due to its short half-life and high reactive activity. With the utilization of P-ONOO, the raised ONOO- was visualized successfully in the drug-treated hepatocytes with a high signal-to-noise ratio via ratiometric and time-resolved photoluminescence imaging. Importantly, the ONOO- boost in the acetaminophen-induced liver injury in real time was verified, and the direct observation of the elevated ONOO- production in ketoconazole-induced liver injury was achieved for the first time. Our findings may contribute to understanding the exact mechanism of ketoconazole-induced hepatotoxicity that is still ambiguous. Notably, this luminescent approach for revealing the liver injury works fast and conveniently.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Substâncias Luminescentes , Imagem Óptica/métodos , Ácido Peroxinitroso , Animais , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico por imagem , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Modelos Animais de Doenças , Irídio/química , Fígado/diagnóstico por imagem , Fígado/metabolismo , Substâncias Luminescentes/análise , Substâncias Luminescentes/química , Substâncias Luminescentes/metabolismo , Camundongos , Camundongos Nus , Ácido Peroxinitroso/análise , Ácido Peroxinitroso/metabolismo , Polímeros/química
15.
Chem Sci ; 10(19): 5085-5094, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31183060

RESUMO

Photosensitizers (PSs) are of particular importance for efficient photodynamic therapy (PDT). Challenges for PSs simultaneously possessing strong light-absorbing ability, high 1O2 generation by effective intersystem crossing from the singlet to the triplet state, good water-solubility and excellent photostability still exist. Reported here are a new kind of dual-emissive semiconducting polymer nanoparticles (SPNs) containing fluorescent BODIPY derivatives and near-infrared (NIR) phosphorescent iridium(iii) complexes. In the SPNs, the BODIPY units serve as the energy donors in the fluorescence resonance energy transfer (FRET) process for enhancing the light absorption of the SPNs. The NIR emissive iridium(iii) complexes are chosen as the energy acceptors and efficient photosensitizers. The ionized semiconducting polymers can easily self-assemble to form hydrophilic nanoparticles and homogeneously disperse in aqueous solution. Meanwhile, the conjugated backbone of SPNs provides effective shielding for the two luminophores from photobleaching. Thus, an excellent overall performance of the SPN-based PSs has been realized and the high 1O2 yield (0.97) resulting from the synergistic effect of BODIPY units and iridium(iii) complexes through the FRET process is among the best reported for PSs. In addition, owing to the phosphorescence quenching of iridium(iii) complexes caused by 3O2, the SPNs can also be utilized for O2 mapping in vitro and in vivo, which assists in the evaluation of the PDT process and provides important instructions in early-stage cancer diagnosis.

16.
ACS Nano ; 13(4): 4804-4813, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30938515

RESUMO

As compared with epitaxial semiconductor devices, two-dimensional (2D) heterostructures offer alternative facile platforms for many optoelectronic devices. Among them, photovoltaic based photodetectors can give fast response, while the photogate devices can lead to high responsivity. Here, we report a 2D photogate photodiode, which combines the benefits of 2D black phosphorus/MoS2 photodiodes with the emerging potential of perovskite, to achieve both fast response and high responsivity. This device architecture is constructed based on the fast photovoltaic operation together with the high-gain photogating effect. Under reverse bias condition, the device exhibits high responsivity (11 A/W), impressive detectivity (1.3 × 1012 Jones), fast response (150/240 µs), and low dark current (3 × 10-11 A). All these results are already much better in nearly all aspects of performance than the previously reported 2D photodiodes operating in reverse bias, achieving the optimal balance between all figure-of-merits. Importantly, with a zero bias, the device can also yield high detectivity (3 × 1011 Jones), ultrahigh light on/off ratio (3 × 107), and extremely high external quantum efficiency (80%). This device architecture thus has a promise for high-efficiency photodetection and photovoltaic energy conversion.

17.
ACS Appl Mater Interfaces ; 10(37): 31008-31018, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30130088

RESUMO

A scalable and low-cost strategy is developed to fabricate a novel CuS/SiO2-based nanotherapeutic agent for dual-model imaging-guided photothermal/photodynamic combined therapy. In this design, mesoporous silica nanoparticles (MSNs) with CuS bundled in the channel are obtained in aqueous solution via in situ growth route for the first time. Furthermore, to achieve a more efficient therapy, photosensitizer (complex Ir-2) and bovine serum albumin are sequentially assembled via layer-by-layer method. The as-prepared complex Ir-2 presents a remarkably high 1O2 generation (ΦΔ = 1.3) under light illumination to offer effective photodynamic cell killing, and MSN/CuS exhibits high photothermal conversion efficiency (η = 31.7%) under illumination by 808 nm light to offer hyperthermia tumor ablation. In vitro and in vivo analyses show that the as-obtained nanotherapeutic agents exhibit excellent performance in tumor therapy even under irradiation with low power because of the high yield of 1O2 combined with the high photothermal conversion efficiency. Additionally, the nanotherapeutic agents are readily visualized in vivo via near-infrared fluorescence and thermal imaging. More importantly, based on the strategy of in situ growth and layer-by-layer assembly developed in this study, the development of other "all-in-one" multifunctional theranostic platform with high efficiency can be predictable.


Assuntos
Cobre/uso terapêutico , Neoplasias/terapia , Fototerapia/métodos , Dióxido de Silício/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Cobre/química , Cobre/farmacologia , Células HeLa , Xenoenxertos , Humanos , Camundongos Endogâmicos BALB C , Distribuição Aleatória , Dióxido de Silício/química , Dióxido de Silício/farmacologia
18.
Adv Healthc Mater ; 7(16): e1800309, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29968378

RESUMO

Peroxynitrite (ONOO- ), a potent biological oxidant, which has a short half-life in physiological conditions, is related to many diseases. Accurate peroxynitrite determination with superior selectivity and sensitivity is important for understanding biological roles of peroxynitrite in different health and disease tissues. Autofluorescence is an inevitable interference in luminescence biodetection and bioimaging, which often reduces signal-to-noise ratio during detection. In this work, a phosphorescent peroxynitrite nanoprobe (MSN-ONOO) which displays two emission bands is prepared by immobilizing two long-lived phosphorescent iridium(III) complexes that are peroxynitrite-activable and -inert, respectively, into water-dispersible mesoporous silica nanoparticles. Owing to the fast response rate, excellent sensitivity and outstanding selectivity of the nanoprobe toward peroxynitrite, it is further used for peroxynitrite determination in vitro and in vivo via ratiometric photoluminescence imaging. More notably, taking advantage of the long-lived phosphorescence of MSN-ONOO, in vivo elevated peroxynitrite is imaged with diminished autofluorescence interference and improved signal-to-noise ratio via time-resolved photoluminescence imaging. As far as it is known, this is the first time for endogenous peroxynitrite detection in vivo via the time-resolved photoluminescence imaging. Furthermore, the production of peroxynitrite in inflamed tissues is visualized.


Assuntos
Luminescência , Nanopartículas/química , Ácido Peroxinitroso/química , Medições Luminescentes , Imagem Óptica/métodos
19.
ACS Appl Mater Interfaces ; 10(21): 17542-17550, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29733202

RESUMO

Temperature plays an important part in many biochemical processes. Accurate diagnosis and proper treatment usually depend on precise measurement of temperature. In this work, a dual-emissive phosphorescent polymer temperature probe, composed of iridium(III) complexes as temperature sensitive unit with phosphorescence lifetime of ∼500 ns and europium(III) complexes as reference unit with lifetime of ∼400 µs, has been rationally designed and synthesized. Upon the increase of the temperature, the luminescence intensity from the iridium(III) complexes is enhanced, while that from the europium(III) complexes remains unchanged, which makes it possible for the ratiometric detection of temperature. Furthermore, the polymer also displays a significant change in emission lifetime accompanied by the temperature variation. By utilizing the laser scanning confocal microscope and time-resolved luminescence imaging systems, ratiometric and time-resolved luminescence imaging in Hela cells and zebrafish have been carried out. Notably, the intensity ratio and long-lifetime-based imaging can offer higher sensitivity, decrease the detection limit, and minimize the background interference from biosamples.


Assuntos
Polímeros/química , Animais , Sobrevivência Celular , Células HeLa , Humanos , Irídio , Temperatura , Peixe-Zebra
20.
Sci Rep ; 5: 16420, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26552859

RESUMO

It is of paramount importance to develop new probes that can selectively, sensitively, accurately and rapidly detect fluoride in aqueous media and biological systems, because F(-) is found to be closely related to many health and environmental concerns. Herein, a dual-emissive conjugated polyelectrolyte P1 containing phosphorescent iridium(III) complex was designed and synthesized, which can form ultrasmall polymer dots (Pdots) in aqueous media. The F(-)-responsive tert-butyldiphenylsilyl moiety was introduced into iridium(III) complex as the signaling unit for sensing F(-) with the quenched phosphorescence. Thus, the dual-emissive Pdots can rapidly and accurately detect F(-) in aqueous media and live cells as a ratiometric probe by measuring the change in the ratio of the F(-)-sensitive red phosphorescence from iridium(III) complex to the F(-)-insensitive blue fluorescence from polyfluorene. Moreover, the interaction of Pdots with F(-) also changes its emission lifetime, and the lifetime-based detection of F(-) in live cells has been realized through photoluminescence lifetime imaging microscopy for the first time. Both the ratiometric luminescence and lifetime imaging have been demonstrated to be resistant to external influences, such as the probe's concentration and excitation power. This study provides a new perspective for the design of promising Pdots-based probes for biological applications.


Assuntos
Fluoretos/química , Polímeros/química , Água/química , Células HeLa , Humanos , Irídio/química , Luminescência , Microscopia Confocal , Imagem Molecular
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