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1.
J Phys Chem Lett ; 13(42): 9855-9861, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36251000

RESUMO

Concentration-dependent phase transitions in concentrated solutions have remained speculation due to the serious impediment of macromolecule dynamics by intensive topological entanglement or intermolecular interaction as well as the absence of powerful tool for detecting changes in chain or segment movement. Herein, taking a general polymer, namely, poly(vinyl alcohol) (PVA), as an example, a water-soluble fluorescent molecule with aggregation-induced emission (AIE) is introduced into the PVA solutions as a chain dynamics indicator to investigate phase transitions at high concentrations through in situ monitoring of the solvent evaporation process. Two turning points of fluorescent intensity are observed for the first time at mean concentrations of ∼25% and ∼45%, corresponding to the gelation and amorphous-to-crystalline transitions, respectively. Our work offers a fundamental insight into the physical nature of concentrate-dependent nonequilibrium transitions and develops a reliable and sensitive approach based on the AIE phenomenon for following high-concentration-triggered property changes of a polymer solution.


Assuntos
Polímeros , Álcool de Polivinil , Fluorescência , Polímeros/química , Álcool de Polivinil/química , Água/química , Solventes , Corantes
2.
Biomaterials ; 288: 121709, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35995625

RESUMO

Real-time intraoperative guidance is essential during various surgical treatment of many diseases. Aggregation-induced emission (AIE) materials have shown great potential for guiding surgeons during complex interventions, with the merits of deep tissue penetration, high quantum yield, high molar absorptivity, low background, good targeting ability and excellent photostability. Herein, we provided insights to design efficient AIE materials regarding three key parameters, i.e., deep-tissue penetration ability, high brightness of AIE luminogens (AIEgens), and precise tumor/other pathology nidus targeting strategies, for realizing better application of fluorescence image-guided surgery. Representative interdisciplinary achievements were outlined for the demonstration of this emerging field. Challenges and future opportunities of AIE materials were briefly discussed. The aim of this review is to provide a comprehensive view of AIE materials for intraoperative guidance for researchers and surgeons, and to inspire more further correlational studies in the new frontiers of image-guided surgery.


Assuntos
Neoplasias , Cirurgia Assistida por Computador , Fluorescência , Corantes Fluorescentes , Humanos
3.
Eur J Nucl Med Mol Imaging ; 49(8): 2560-2583, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35277741

RESUMO

Photoacoustic imaging (PAI) is a rapidly emerging modality in biomedical research with the advantages of noncontact operation, high optical resolution, and deep penetration. Great efforts and progress in the development of PAI agents with improved imaging resolution and sensitivity have been made over the past 2 decades. Among them, organic agents are the most promising candidates for preclinical/clinical applications due to their outstanding in vivo properties and facile biofunctionalities. Motivated by the unique properties of aggregation-induced emission (AIE) luminogens (AIEgens), various optical probes have been developed for bioanalyte detection, multimodal bioimaging, photodynamic/photothermal therapy, and imaging-guided therapeutics. In particular, AIE-active contrast agents have been demonstrated in PAI applications with excellent performance in imaging resolution and tissue permeability in vivo. This paper presents a brief overview of recent progress in AIE-based agents in the field of photoacoustic imaging. In particular, we focus on the basic concepts, data sorting and comparison, developing trends, and perspectives of photoacoustic imaging. Through numerous typical examples, the way each system realizes the desired photoacoustic performance in various biomedical applications is clearly illustrated. We believe that AIE-based PAI agents would be promising multifunctional theranostic platforms in clinical fields and will facilitate significant advancements in this research topic.


Assuntos
Técnicas Fotoacústicas , Fotoquimioterapia , Meios de Contraste , Diagnóstico por Imagem , Corantes Fluorescentes , Humanos , Imagem Óptica/métodos , Técnicas Fotoacústicas/métodos , Fotoquimioterapia/métodos , Nanomedicina Teranóstica/métodos
4.
Chemistry ; 27(67): 16690-16700, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34634149

RESUMO

Organic materials with multiple emissions tunable by external stimuli represent a great challenge. TTPyr, crystallizing in different polymorphs, shows a very rich photophyisics comprising excitation-dependent fluorescence and phosphorescence at ambient conditions, and mechanochromic and thermochromic behavior. Transformation among the different species has been followed by thermal and X-ray diffraction analyses and the emissive features interpreted through structural results and DFT/TDDFT calculations. Particularly intriguing is the polymorph TTPyr(HT), serendipitously obtained at high temperature but stable also at room temperature, whose non-centrosymmetric structure guarantees an SHG efficiency 10 times higher than that of standard urea. Its crystal packing, where only the TT units are strongly rigidified by π-π stacking interactions while the Pyr moieties possess partial conformational freedom, is responsible for the observed dual fluorescence. The potentialities of TTPyr for bioimaging have been successfully established.


Assuntos
Luminescência , Pirenos , Cristalografia por Raios X , Conformação Molecular , Temperatura
5.
Theranostics ; 9(11): 3223-3248, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244951

RESUMO

Pathogenic bacteria, fungi and viruses pose serious threats to the human health under appropriate conditions. There are many rapid and sensitive approaches have been developed for identification and quantification of specific pathogens, but many challenges still exist. Culture/colony counting and polymerase chain reaction are the classical methods used for pathogen detection, but their operations are time-consuming and laborious. On the other hand, the emergence and rapid spread of multidrug-resistant pathogens is another global threat. It is thus of utmost urgency to develop new therapeutic agents or strategies. Luminogens with aggregation-induced emission (AIEgens) and their derived supramolecular systems with unique optical properties have been developed as fluorescent probes for turn-on sensing of pathogens with high sensitivity and specificity. In addition, AIE-based supramolecular nanostructures exhibit excellent photodynamic inactivation (PDI) activity in aggregate, offering great potential for not only light-up diagnosis of pathogen, but also image-guided PDI therapy for pathogenic infection.


Assuntos
Anti-Infecciosos/administração & dosagem , Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/tratamento farmacológico , Testes Diagnósticos de Rotina/métodos , Corantes Fluorescentes/química , Substâncias Macromoleculares/metabolismo , Nanomedicina Teranóstica/métodos , Animais , Anti-Infecciosos/farmacologia , Humanos , Nanopartículas Multifuncionais/administração & dosagem , Nanopartículas Multifuncionais/metabolismo , Imagem Óptica/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/farmacologia , Sensibilidade e Especificidade
6.
Theranostics ; 8(18): 4925-4956, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30429878

RESUMO

The utilization of luminogens with aggregation-induced emission (AIE) characteristics has recently been developed at a tremendous pace in the area of theranostics, mainly because AIE luminogens (AIEgens) hold various distinct advantages, such as good biocompatibility, excellent fluorescence properties, simple preparation and modification, perfect size of nano-aggregation for enhanced permeability and retention effect, promoted efficiencies of photodynamic and photothermal therapies, efficient photoacoustic imaging, and ready constructions of multimodal imaging and therapy. Significant breakthroughs and developments of theranostics based on AIEgens have been achieved in the past few years, and great progress has been witnessed in many theranostic modalities, indicating that AIEgens remarkably complement conventional theranostic materials and promote the development of theranostics. This review provides theoretical insights into the advantages of AIEgens in theranostics, and systematically summarizes the basic concepts, seminal studies, recent trends and perspectives in theranostics based on AIEgens. We believe that AIEgens would be promising multifunctional theranostic platforms in clinical fields and facilitate significant advancements in this research-active area.


Assuntos
Imagem Molecular/métodos , Terapia de Alvo Molecular/métodos , Nanomedicina/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Nanomedicina Teranóstica/métodos , Animais , Modelos Animais de Doenças , Nanomedicina/tendências , Nanomedicina Teranóstica/tendências
7.
Small ; 13(7)2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27930860

RESUMO

A new drug concentration meter is developed. In vivo drug release can be monitored precisely via a self-indicating drug delivery system consisting of a new aggregation-induced emission thermoresponsive hydrogel. By taking the advantage of a self-indicating system, one can easily detect the depletion of drugs, and reinject to maintain a dosage in the optimal therapeutic window.


Assuntos
Sistemas Computacionais , Liberação Controlada de Fármacos , Géis/química , Polímeros/química , Temperatura , Células A549 , Animais , Células Hep G2 , Humanos , Camundongos , Polímeros/síntese química , Fatores de Tempo
8.
Adv Healthc Mater ; 5(4): 427-31, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26688031

RESUMO

In this work, a morpholine-functionalized aggregation-induced emission luminogen (AIEgen), AIE-LysoY, is reported for lysosomal imaging and autophagy visualization. To attain outstanding imaging contrast, AIE-LysoY is equipped with excited state intramolecular proton transfer (ESIPT) characteristic. AIE-LysoY provides a new platform for lysosome visualization with good biocompatibility, large Stokes shift, superior signal-to-noise ratio, and high photostability.


Assuntos
Autofagia , Lisossomos/metabolismo , Sondas Moleculares/química , Morfolinas/química , Materiais Biocompatíveis/química , Sobrevivência Celular , Células HeLa , Humanos , Microscopia de Fluorescência , Prótons , Razão Sinal-Ruído
9.
Chem Commun (Camb) ; 51(10): 1866-9, 2015 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-25526628

RESUMO

We report a fluorophore, TPE-TPP, with AIE characteristics which is utilized as a fluorescence probe to monitor the α-synuclein (α-Syn) fibrillation process. Compared with ThT, TPE-TPP shows a higher sensitivity in the detection of α-Syn oligomers as well as fibrils with a stronger fluorescence. The performance of TPE-TPP was evaluated using fluorescence, AFM, dot blot, and SEC.


Assuntos
Corantes Fluorescentes , Compostos Organofosforados/síntese química , Estilbenos/síntese química , alfa-Sinucleína/análise , Motivos de Aminoácidos , Fluorescência , Estrutura Molecular , Compostos Organofosforados/química , Estilbenos/química , alfa-Sinucleína/química
10.
ACS Appl Mater Interfaces ; 5(17): 8784-9, 2013 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-23957823

RESUMO

Fluorogens with aggregation-induced emission (AIE) characteristics have attracted intensified research interest in biosensing applications, and those with specific targeting ability are especially desirable. In this work, we designed and synthesized an AIE fluorescent probe by functionalizing a tetraphenylethylene (TPE) fluorogen with two phosphate groups (TPE-phos) for the detection of alkaline phosphatase (ALP) and its enzymatic activity based on the specific interaction between the probe and ALP. The probe is virtually nonfluorescent in aqueous media due to good water solubility. In the presence of ALP, the phosphate groups are cleaved through enzymatic hydrolysis, yielding a highly fluorescent product as a result of activated AIE process. This light-up probe shows excellent selectivity toward ALP among a group of proteins. The detection limit is found to be 11.4 pM or 0.2 U L(-1) in Tris buffer solution with a linear quantification range of 3-526 U L(-1). The assay is also successfully performed in diluted serum with a linear range up to 175 U L(-1), demonstrating its potential application in clinical analysis of ALP levels in real samples. Furthermore, by conducting kinetic analysis of the enzyme using TPE-phos as the substrate, the kinetic parameter kcat/KM is determined to be 5.1×10(5) M(-1) s(-1), indicating a high efficiency of the substrate.


Assuntos
Fosfatase Alcalina/análise , Corantes Fluorescentes/química , Espectrometria de Fluorescência , Ensaios Enzimáticos , Corantes Fluorescentes/síntese química , Hidrólise , Cinética
11.
ACS Appl Mater Interfaces ; 3(9): 3411-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21834577

RESUMO

Terpyridine-containing tetraphenylethenes (TPEs) are synthesized and their optical and metal sensing properties are investigated. They are practically nonluminescent in the solution state but become highly emissive as nanoparticle suspensions in poor solvents or thin films in the solid state, demonstrating a novel phenomenon of aggregation-induced emission (AIE). The emission of the nanoaggregates of TPEs is pH-sensitive: it is decreased and eventually quenched upon protonation of their terpyridine units because of their AIE nature. The TPEs can work as "turn-off" fluorescent chemosensors for metal ions and display different fluorescence responses to various metal ions. A characteristic red shift in the emission spectra is observed in the presence of Zn(2+), which facilitates the discrimination of Zn(2+) from other metal ions. Because of the metal-to-ligand-charge-transfer process, terpyridine-substituted TPEs display an obvious magenta color upon selectively binding with Fe(2+), allowing a rapid identification of Fe(2+) in the aqueous media by naked eyes.


Assuntos
Etilenos/química , Compostos Ferrosos/análise , Corantes Fluorescentes/química , Piridinas/química , Espectrofotometria Ultravioleta/métodos , Zinco/análise , Polimetil Metacrilato/química
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