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1.
Chem Commun (Camb) ; 57(40): 4902-4905, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-33870972

RESUMO

A bromine-substituted thermally activated delayed fluorescent (TADF) molecule AQCzBr2 is designed with both small singlet-triplet splitting (ΔEST) and increased spin-orbit coupling (SOC) to boost intersystem crossing (ISC) for singlet oxygen generation. AQCzBr2 nanoparticles (NPs) demonstrate high productivity of singlet oxygen generation (ΦΔ = 0.91) which allows highly efficient photodynamic therapy toward cancer cells.

2.
Angew Chem Int Ed Engl ; 60(5): 2478-2484, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33080106

RESUMO

Developing red thermally activated delayed fluorescence (TADF) emitters for high-performance OLEDs is still facing great challenge. Herein, three red TADF emitters, pDBBPZ-DPXZ, pDTBPZ-DPXZ, and oDTBPZ-DPXZ, are designed and synthesized with same donor-acceptor (D-A) backbone with different peripheral groups attaching on the A moieties. Their lowest triplet states change from locally excited to charge transfer character leading to significantly enhance reverse intersystem crossing process. In particular, oDTBPZ-DPXZ exhibits efficient TADF feature and exciton utilization. It not only achieves an external quantum efficiency (EQE) of 20.1 % in red vacuum-processed OLED, but also realize a high EQE of 18.5 % in a solution-processed OLED, which is among the best results in solution-processed red TADF OLEDs. This work provides an effective strategy for designing red TADF molecules by managing energy level alignments to facilitate the up-conversion process and thus enhance exciton harvesting.

3.
Small ; 16(34): e2002672, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32697430

RESUMO

Multi-modality imaging-guided cancer therapy is considered as a powerful theranostic platform enabling simultaneous precise diagnosis and treatment of cancer. However, recently reported multifunctional systems with multiple components and sophisticate structures remain major obstacles for further clinical translation. In this work, a single-photomolecular theranostic nanoplatform is fabricated via a facile nanoprecipitation strategy. By encapsulating a semiconductor oligomer (IT-S) into an amphiphilic lipid, water-dispersible IT-S nanoparticles (IT-S NPs) are prepared. The obtained IT-S NPs have a very simple construction and possess ultra-stable near-infrared (NIR) fluorescence (FL)/photoacoustic (PA) dual-modal imaging and high photothermal conversion efficiency of 72.3%. Accurate spatiotemporal distribution profiles of IT-S NPs are successfully visualized by NIR FL/PA dual-modal imaging. With the comprehensive in vivo imaging information provided by IT-S NPs, tumor photothermal ablation is readily realized under precise manipulation of laser irradiation, which greatly improves the therapeutic efficacy without any obvious side effects. Therefore, the IT-S NPs allow high tumor therapeutic efficacy under the precise guidance of FL/PA imaging techniques and thus hold great potential as an effective theranostic platform for future clinical applications.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Técnicas Fotoacústicas , Linhagem Celular Tumoral , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Imagem Óptica , Fototerapia , Nanomedicina Teranóstica
4.
ACS Nano ; 14(8): 9917-9928, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32706236

RESUMO

Effective multimodality phototheranostics under deep-penetration laser excitation is highly desired for tumor medicine, which is still at a deadlock due to lack of versatile photosensitizers with absorption located in the long-wavelength region. Herein, we demonstrate a stable organic photosensitizer nanoparticle based on molecular engineering of benzo[c]thiophene (BT)-based photoactivated molecules with strong wavelength-tunable absorption in the near-infrared region. Via molecular design, the absorption and singlet oxygen generation of BT molecules would be reliably tuned. Importantly, the nanoparticles with a red-shifted absorption peak of 843 nm not only show over 10-fold reactive oxygen species yield compared with indocyanine green but also demonstrate a notable photothermal effect and photoacoustic signal upon 808 nm excitation. The in vitro and in vivo experiments substantiate good multimodal anticancer efficacy and imaging performance of BT theranostics. This work provides an organic photosensitizer nanoparticle with long-wavelength excitation and high photoenergy conversion efficiency for multimodality phototherapy.


Assuntos
Nanopartículas , Fármacos Fotossensibilizantes , Fototerapia , Espécies Reativas de Oxigênio , Nanomedicina Teranóstica
5.
ACS Nano ; 13(11): 12901-12911, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31682416

RESUMO

We developed a biodegradable photothermal therapeutic (PTT) agent, π-conjugated oligomer nanoparticles (F8-PEG NPs), for highly efficient cancer theranostics. By exploiting an oligomer with excellent near-infrared (NIR) absorption, the nanoparticles show a high photothermal conversion efficiency (PCE) up to 82%, surpassing those of reported inorganic and organic PTT agents. In addition, the oligomer nanoparticles show excellent photostability and good biodegradability. The F8-PEG NPs are also demonstrated to have excellent biosafety and PTT efficacy both in vitro and in vivo. This contribution not only proposes a promising oligomer-based PTT agent but also provides insight into developing highly efficient nanomaterials for cancer theranostics.


Assuntos
Nanopartículas/química , Neoplasias/terapia , Fototerapia , Nanomedicina Teranóstica , Células A549 , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Camundongos , Nanopartículas/metabolismo , Neoplasias/patologia
6.
BMC Genomics ; 20(1): 877, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31747870

RESUMO

BACKGROUND: Cadmium (Cd) is a serious heavy metal (HM) soil pollutant. To alleviate or even eliminate HM pollution in soil, environmental-friendly methods are applied. One is that special plants are cultivated to absorb the HM in the contaminated soil. As an excellent economical plant with ornamental value and sound adaptability, V. bonariensis could be adapted to this very situation. In our study, the Cd tolerance in V. bonariensis was analyzed as well as an overall analysis of transcriptome. RESULTS: In this study, the tolerance of V. bonariensis to Cd stress was investigated in four aspects: germination, development, physiological changes, and molecular alterations. The results showed that as a non-hyperaccumulator, V. bonariensis did possess the Cd tolerance and the capability to concentration Cd. Under Cd stress, all 237, 866 transcripts and 191, 370 unigenes were constructed in the transcriptome data of V. bonariensis roots. The enrichment analysis of gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway revealed that differentially expressed genes (DEGs) under Cd stress were predominately related to cell structure, reactive oxygen species (ROS) scavenging system, chelating reaction and secondary metabolites, transpiration and photosynthesis. DEGs encoding lignin synthesis, chalcone synthase (CHS) and anthocyanidin synthase (ANS) were prominent in V. bonariensis under Cd stress. The expression patterns of 10 DEGs, validated by quantitative real-time polymerase chain reaction (qRT-PCR), were in highly accordance with the RNA-Sequence (RNA-Seq) results. The novel strategies brought by our study was not only benefit for further studies on the tolerance of Cd and functional genomics in V. bonariensis, but also for the improvement molecular breeding and phytoremediation.


Assuntos
Cádmio/toxicidade , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Poluentes do Solo/toxicidade , Transcriptoma , Verbena/efeitos dos fármacos , Aciltransferases/genética , Aciltransferases/metabolismo , Adaptação Fisiológica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , Germinação/efeitos dos fármacos , Germinação/genética , Anotação de Sequência Molecular , Oxigenases/genética , Oxigenases/metabolismo , Fotossíntese/efeitos dos fármacos , Fotossíntese/genética , Proteínas de Plantas/classificação , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Transpiração Vegetal/efeitos dos fármacos , Transpiração Vegetal/genética , Espécies Reativas de Oxigênio/metabolismo , Metabolismo Secundário/efeitos dos fármacos , Metabolismo Secundário/genética , Estresse Fisiológico , Verbena/genética , Verbena/crescimento & desenvolvimento , Verbena/metabolismo
7.
Small ; 15(38): e1903121, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31379108

RESUMO

The combination of diagnostic and therapeutic functions in a single theranostic nanoagent generally requires the integration of multi-ingredients. Herein, a cytotoxic near-infrared (NIR) dye (IR-797) and its nanoassembly are reported for multifunctional cancer theranostics. The hydrophobic IR-797 molecules are self-assembled into nanoparticles, which are further modified with an amphiphilic polymer (C18PMH-PEG5000) on the surface. The prepared PEG-IR-797 nanoparticles (PEG-IR-797 NPs) possess inherent cytotoxicity from the IR-797 dye and work as a chemotherapeutic drug which induces apoptosis of cancer cells. The IR-797 NPs are found to have an ultrahigh mass extinction coefficient (444.3 L g-1 cm-1 at 797 nm and 385.9 L g-1 cm-1 at 808 nm) beyond all reported organic nanomaterials (<40 L g-1 cm-1 ) for superior photothermal therapy (PTT). In addition, IR-797 shows some aggregation-induced-emission (AIE) properties. Combining the merits of good NIR absorption, high photothermal energy conversion efficiency, and AIE, makes the PEG-IR-797 NPs useful for multimodal NIR AIE fluorescence, photoacoustic, and thermal imaging-guided therapy. The research exhibits the possibility of using a single ingredient and entity to perform multimodal NIR fluorescence, photoacoustic, and thermal imaging-guided chemo-/photothermal combination therapy, which may trigger wide interest from the fields of nanomedicine and medicinal chemistry to explore multifunctional theranostic organic molecules.


Assuntos
Antineoplásicos/química , Nanomedicina Teranóstica/métodos , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Técnicas Fotoacústicas/métodos , Fotoquimioterapia/métodos , Polímeros/química
8.
ACS Appl Mater Interfaces ; 11(32): 29086-29093, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31329407

RESUMO

Development of red thermally activated delayed fluorescence (TADF) emitters has been lagging behind when compared with those of blue and green fluorophores, especially for solution-processable ones. In this work, two novel orange-red TADF emitters 3,6-di(10H-phenoxazin-10-yl)dibenzo[a,c]phenazine (DBPZ-DPXZ) and 10,10'-(11,12-bis(3,5-di-tert-butylphenyl)dibenzo[a,c]phenazine-3,6-diyl)bis(10H-phenoxazine) (tDBBPZ-DPXZ) are developed. A high-performance orange-red TADF emitter, DBPZ-DPXZ, is first prepared by connecting a rigid acceptor and two rigid donor segments. While this design strategy endows DBPZ-DPXZ with an excellent TADF performance leading to a vacuum-processed organic light-emitting diode (OLED) with a high external quantum efficiency (EQE) of 17.8%, the rigid segments limit its solubility and applications in solution-processed devices. Based on this prototype, tDBBPZ-DPXZ is designed with the addition of 3,5-di-tert-butylphenyl groups to boost its solubility with barely an influence on the photophysical properties. In particular, tDBBPZ-DPXZ maintains nearly an identical photoluminescence quantum yield of 83% and singlet-triplet energy splitting of 0.03 eV with EQE of 17.0% in a vacuum-processed orange-red OLED. Furthermore, it can be applied on the orange-red solution-processed OLED realizing an EQE as high as 10.1%, representing one of the state-of-the-art results of the reported orange-red solution-processed TADF-OLEDs. This work provides an effective strategy to address the conflicting requirements between high efficiency and good solubility and develop efficient soluble orange-red TADF emitters.

9.
Angew Chem Int Ed Engl ; 58(41): 14660-14665, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31313424

RESUMO

Developing red thermally activated delayed fluorescence (TADF) emitters, attainable for both high-efficient red organic light-emitting diodes (OLEDs) and non-doped deep red/near-infrared (NIR) OLEDs, is challenging. Now, two red emitters, BPPZ-PXZ and mDPBPZ-PXZ, with twisted donor-acceptor structures were designed and synthesized to study molecular design strategies of high-efficiency red TADF emitters. BPPZ-PXZ employs the strictest molecular restrictions to suppress energy loss and realizes red emission with a photoluminescence quantum yield (ΦPL ) of 100±0.8 % and external quantum efficiency (EQE) of 25.2 % in a doped OLED. Its non-doped OLED has an EQE of 2.5 % owing to unavoidable intermolecular π-π interactions. mDPBPZ-PXZ releases two pyridine substituents from its fused acceptor moiety. Although mDPBPZ-PXZ realizes a lower EQE of 21.7 % in the doped OLED, its non-doped device shows a superior EQE of 5.2 % with a deep red/NIR emission at peak of 680 nm.

10.
Chem Sci ; 11(3): 888-895, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-34123067

RESUMO

Rational manipulation of energy utilization from excited-state radiation of theranostic agents with a donor-acceptor structure is relatively unexplored. Herein, we present an effective strategy to tune the exciton dynamics of radiative excited state decay for augmenting two-photon nanotheranostics. As a proof of concept, two thermally activated delayed fluorescence (TADF) molecules with different electron-donating segments are engineered, which possess donor-acceptor structures and strong emissions in the deep-red region with aggregation-induced emission characteristics. Molecular simulations demonstrate that change of the electron-donating sections could effectively regulate the singlet-triplet energy gap and oscillator strength, which promises efficient energy flow. A two-photon laser with great permeability is used to excite TADF NPs to perform as theranostic agents with singlet oxygen generation and fluorescence imaging. These unique performances enable the proposed TADF emitters to exhibit tailored balances between two-photon singlet oxygen generation and fluorescence emission. This result demonstrates that TADF emitters can be rationally designed as superior candidates for nanotheranostic agents by the custom controlling exciton dynamics.

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