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1.
Front Chem ; 9: 781294, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34888296

RESUMO

Recently, there has been remarkable progress of the host-guest doped pure organic room-temperature phosphorescence (RTP) materials. However, it remains a great challenge to develop highly efficient host-guest doping systems. In this study, we have successfully developed a heavy atom free pure organic molecular doped system (benzophenone-thianthrene, respectively) with efficient RTP through a simple host-guest doping strategy. Furthermore, by optimizing the doping ratios, the host-guest material with a molar ratio of 100:1 presented an efficient RTP emission with 46% quantum efficiency and a long lifetime of up to 9.17 ms under ambient conditions. This work will provide an effective way to design new organic doping systems with RTP.

2.
Immunobiology ; 227(1): 152165, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34936966

RESUMO

Chronic inflammation contributes to cancer development and progression. Although interleukin-1beta (IL-1ß) has been observed to be associated with an general immune suppression of T cell response and the immunosuppression strongly correlates with accumulation of myeloid-derived suppressor cells (MDSCs), the relationship and mechanism between MDSCs expansion and IL-1ß expression remain ambiguous. Here, we showed that the concentration of IL-1ß was highly correlated with G-MDSC subset, rather than mo-MDSC subset. Recombinant IL-1ß increased the percentage of G-MDSCs in the blood of tumor-bearing mice, and IL-1Ra attenuated the accumulation of G-MDSCs in the tumor-bearing mice. In addition, the IL-1ß-overexpressing B16F10 cells induced higher level of G-MDSCs compared with wild-type B16F10 cells. Moreover, we found that the accumulation of G-MDSCs induced by IL-1ß was dependent on the activation of extracellular signal-regulated kinases 1 and 2 (Erk1/2). Collectively, these findings show a novel role of IL-1ß in G-MDSCs accumulation by activating Erk1/2, which suggests that IL-1ß elimination or Erk1/2 signaling blockade could decrease G-MDSCs generation and thereby improve host immunosurveillance.

3.
Adv Mater ; : e2107612, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34806790

RESUMO

Room temperature phosphorescence (RTP) has been extensively researched in heavy-metal containing complexes and purely organic system. Despite the rapid blossom of RTP materials, it is still a tremendous challenge to develop highly efficient blue RTP materials with long-lived lifetimes. Taking the metal organic framework (MOF) as a model, we herein propose a feasible strategy of ligand functionalization, including two essential elements, to develop blue phosphorescence materials with high efficiency and long-lived lifetimes simultaneously under ambient conditions. One is isolation of the chromophores with assistance of another predefined co-ligands, the other is restriction of the chromophores' motions through coordination and host-guest interactions. Remarkably, it renders the MOFs with high efficient blue phosphorescence up to 80.6% and a lifetime of 169.7 ms under ambient conditions. Moreover, a demo of the crown is fabricated with MOFs ink by 3D printing technique. The potential applications for anti-counterfeiting and fingerprint visualization were also demonstrated. This finding not only outlines a universal principle to design and synthesize highly efficient RTP materials, but also endows traditional MOFs with fresh vitality for potential applications. This article is protected by copyright. All rights reserved.

4.
Phytomedicine ; 93: 153788, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34634745

RESUMO

BACKGROUND: Sono-photodynamic therapy (SPDT) which is the combination of photodynamic therapy (PDT) and sonodynamic therapy (SDT), could exert much better anti-cancer effects than monotherapy. The combination of chemotherapy and PDT or SDT has shown great potential for cancer treatment. However, the combination of SPDT and chemotherapy for cancer treatment is rarely explored. PURPOSE: We utilized a natural hydrophobic anti-cancer drug oleanolic acid (OA) and a photosensitizer chlorin e6 (Ce6) through self-assembly technology to form a carrier-free nanosensitizer OC for combined chemotherapy and SPDT for cancer treatment. No studies involving using carrier-free nanomedicine for combined chemotherapy/SPDT have been reported yet. STUDY DESIGN: After fully characterization of OC, the in vitro and in vivo anti-cancer activities of OC were investigated and the mechanisms of the synergistic therapeutic effects were studied. METHODS: OC were synthesized through self-assembly technology and characterized by dynamic light scattering (DLS) and an atomic force microscope (AFM). Confocal microscope was used to investigate the intracellular uptake efficiency and the penetration ability of OC. The cell viability of PC9 and 4T1 cells treated with OC under laser and ultrasound (US) irradiation was determined by MTT assay. Furthermore, flow cytometry was performed to detect the reactive oxygen species (ROS) generation, loss of mitochondrial membrane potential (MMP), cell apoptosis and cell cycle arrest. Finally, the anti-tumor therapeutic efficacy of OC was investigated in orthotopic 4T1 breast tumor-bearing mouse model. RESULTS: OC showed an average particle size of around 100 nm with excellent light stability. OC increased more than 23 times accumulation of Ce6 in cancer cells and had strong tumor penetration ability in three-dimensional (3D) multicellular tumor spheroids (MCTSs). Compared with other therapeutic options, OC showed obvious synergistic inhibitory effects under light and US irradiation in PC9 and 4T1 cells with a significant decrease in IC50 values. Mechanism studies showed that OC could generate high ROS, induce MMP loss, and cause apoptosis and cell cycle arrest. In vivo studies also approved the synergistic therapeutic effects of OC in 4T1 mouse models. CONCLUSION: Self-assembled carrier-free nanosensitizer OC could be a promising therapeutic agent for synergistic chemo/sono-photodynamic therapy for cancer treatment.


Assuntos
Nanopartículas , Neoplasias , Ácido Oleanólico , Fotoquimioterapia , Porfirinas , Animais , Linhagem Celular Tumoral , Clorofilídeos , Humanos , Camundongos , Ácido Oleanólico/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia
5.
Anal Chem ; 93(44): 14643-14650, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34698497

RESUMO

Glycosylation is one of the most ubiquitous and complicated modifications of proteins and lipids. The revelation of glycosylation-mediated regulation mechanisms of biological processes relies critically on the tools that can reflect the spatial heterogeneity of cell surface glycans, for example, distinguishing glycans exhibited in lipid raft or nonraft domains. To achieve simultaneous visualization of raft and raft-harbored glycans on the cell surface, we combine specific raft recognition, glycan chemoselective labeling, and DNA dynamic hybridization techniques to develop a hierarchical fluorescence imaging strategy using N-acetyl-neuraminic acid (Sia) as the model sugar. We fabricate a raft probe and Sia probe for rafts and Sia, respectively. After specifically anchoring the two probes on the cell surface, the raft probe can be cyclically utilized to turn on the fluorescence of the Sia probe, only residing in rafts, via a proximity cascade DNA reaction. The duplex imaging capability for spatially relevant levels of biological structures enables the revelation of the reason for raft-confined Sia variation in different biological processes. Thus, this work provides an elegant and powerful tool for interrogation of the glycan regulation mechanisms on raft composition, organization, and functions and also contributes to the development of raft-carried glycoconjugate-based theranostic techniques.


Assuntos
Lipídeos , Microdomínios da Membrana , Membrana Celular , Imagem Óptica
6.
J Am Chem Soc ; 143(39): 16256-16263, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34550674

RESUMO

Ultralong organic phosphorescence (UOP) has aroused enormous interest in recent years. UOP materials are mainly limited to crystals or rigid host-guest systems. Their poor processability and mechanical properties critically hamper practical applications. Here, we reported a series of ultralong phosphorescent foams with high mechanical strength. Phosphorescence lifetime of the foam can reach up to 485.8 ms at room temperature. Impressively, lightweight gelatin foam can bear a compressive pressure of 4.44 MPa. Moreover, phosphorescence emission of polymer foam can be tuned from blue to orange through varying the excitation wavelength. Experimental data and theoretical calculations revealed that ultralong phosphorescence was ascribed to the fixation of multiple hydrogen bonds to the clusters of carbonyl groups. These results will allow for expanding the scope of luminescent foams, providing an ideal platform for developing ultralong phosphorescent materials with high mechanical strength.

7.
Front Chem ; 9: 740018, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34552914

RESUMO

Purely aromatic hydrocarbon materials with ultralong room-temperature phosphorescence (RTP) were reported recently, but which is universally recognized as unobservable. To reveal the inherent luminescent mechanism, two compounds, i.e., PT with a faint RTP and HD with strong RTP featured by nonplanar geometry, were chosen as a prototype to study their excited-state electronic structures by using quantum mechanics/molecular mechanics (QM/MM) model. It is demonstrated that the nonplanar ethylene brides can offer σ-electron to strengthen spin-orbit coupling (SOC) between singlet and triplet excited states, which can not only promote intersystem crossing (ISC) of S1→Tn to increase the population of triplet excitons, but also accelerate the radiative decay rate of T1→S0, and thus improving RTP. Impressively, the nonradiative decay rate only has a small increase, owing to the synergistic effect between the increase of SOC and the reduction of reorganization energy of T1→S0 caused by the restricted torsional motions of aromatic rings. Therefore, a bright and long-lived RTP was obtained in aromatic hydrocarbon materials with twisted structure. This work provided a new insight into the ultralong RTP in pure organic materials.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34532938

RESUMO

There are few reports about purely organic phosphorescence scintillators, and the relationship between molecular structures and radioluminescence in organic scintillators is still unclear. Here, we presented isomerism strategy to study the effect of molecular structures on radioluminescence. The isomers can achieve phosphorescence efficiency of up to 22.8 % by ultraviolet irradiation. Under X-ray irradiation, both m-BA and p-BA show excellent radioluminescence, while o-BA has almost no radioluminescence. Through experimental and theoretical investigation, we found that radioluminescence was not only affected by non-radiation in emissive process, but also highly depended on the material conductivity caused by the different molecular packing. This study not only allows us to clearly understand the relationship between the molecular structures and radioluminescence, but also provides a guidance to rationally design new organic scintillators.

9.
ACS Appl Mater Interfaces ; 13(37): 44065-44078, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34515464

RESUMO

The impact of the mechanical properties of nanomedicines on their biological functions remains elusive due to the difficulty in tuning the elasticity of the vehicles without changing chemistry. Herein, we report the fabrication of elasticity-tunable self-assembled oleanolic acid (OA) nanoconstructs in an antiparallel zigzag manner and develop rigid nanoparticles (OA-NP) and flexible nanogels (OA-NG) as model systems to decipher the elasticity-biofunction relationship. OA-NG demonstrate less endocytosis and enhanced lysosome escape with deformation compared to OA-NP. Further in vitro and in vivo experiments show the active permeation of OA-NG into the interior of tumor with enhanced antitumor efficacy accompanied by decreased collagen production and eight- to tenfold immune cell infiltration. This study not only presents a facile and green strategy to develop flexible OA-NG for effective cancer treatment but also uncovers the crucial role of elasticity in regulating biological activity, which may provide reference for precise design of efficient nanomedicines.

10.
Nat Mater ; 20(11): 1539-1544, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34426660

RESUMO

High-efficiency blue phosphorescence emission is essential for organic optoelectronic applications. However, synthesizing heavy-atom-free organic systems having high triplet energy levels and suppressed non-radiative transitions-key requirements for efficient blue phosphorescence-has proved difficult. Here we demonstrate a simple chemical strategy for achieving high-performance blue phosphors, based on confining isolated chromophores in ionic crystals. Formation of high-density ionic bonds between the cations of ionic crystals and the carboxylic acid groups of the chromophores leads to a segregated molecular arrangement with negligible inter-chromophore interactions. We show that tunable phosphorescence from blue to deep blue with a maximum phosphorescence efficiency of 96.5% can be achieved by varying the charged chromophores and their counterions. Moreover, these phosphorescent materials enable rapid, high-throughput data encryption, fingerprint identification and afterglow display. This work will facilitate the design of high-efficiency blue organic phosphors and extend the domain of organic phosphorescence to new applications.

11.
Chem Commun (Camb) ; 57(59): 7276-7279, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34196639

RESUMO

Three kinds of microstructures were prepared for one organic phosphor based on a solution-concentration-controlled self-assembly strategy. These microstructures show different phosphorescence efficiencies, which holds considerable promise for the miniaturized optical device applications of ultralong organic phosphorescence materials.

12.
Anal Chem ; 93(16): 6516-6522, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33852275

RESUMO

Compared with short-lived emission probes featuring fluorescence imaging , the use of phosphorescent probes imparts the advantage of long-lived signal persistence that distinguishes against background fluorescence interference. However, the realization of ultralong organic phosphorescent (UOP) probes with an ultralong emission lifetime in an aqueous medium is still a challenge. Here, we present a rational strategy for obtaining UOP nanoparticles (NPs) in an air-saturated aqueous medium prepared using an organic phosphor (PDBCz) and a surfactant polymer (PVP), named PDBCz@PVP, showing an ultralong emission lifetime of 284.59 ms and a phosphorescence quantum efficiency of 7.6%. The excellent phosphorescence properties and water solubility of PDBCz@PVP make it a promising candidate for biological imaging. The as-prepared PDBCz@PVP NPs possess excellent luminescence intensity as well as illustrious biocompatibility both in vitro and in vivo. We demonstrate their use as an efficient phosphorescent nanoprobe both in living cells and zebrafish by capturing their afterglow emission signals under microscopy observation for the first time, realizing convenient and fast bioimaging with low cost, which allows for anti-fluorescence interference and shows promise for the future theragnostic applications in nanomedicine.


Assuntos
Medições Luminescentes , Nanopartículas , Peixe-Zebra , Animais , Luminescência , Polímeros
13.
Life Sci ; 275: 119273, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33631172

RESUMO

AIMS: Postmenopausal osteoporosis (PMOP) is a growing health problem affecting many postmenopausal women. This study intended to identify the role of dexmedetomidine (Dex) in osteoporosis (OP). MAIN METHODS: Microarray analysis was performed for the gene expression profiles of PMOP patients and postmenopausal healthy volunteers, and the most differentially expressed microRNA (miR)-361-5p was verified in clinic, and its diagnostic value in PMOP patients was analyzed. After establishment of OP model by ovariectomy, Dex treatment and overexpression of miR-361-5p or vascular endothelial growth factor A (VEGFA) were performed in OP rats or isolated bone marrow mesenchymal stem cells (BMSCs). Bone mineral density (BMD) related indexes and levels of osteogenesis-angiogenesis related genes were measured. The apoptosis and osteogenic differentiation of BMSCs were detected. After human umbilical vein endothelial cells (HUVECs) and BMSCs were cocultured, the angiogenesis of BMSCs was detected by Matrigel-based angiogenesis experiment. KEY FINDINGS: miR-361-5p was highly expressed in PMOP patients and OP rats, with good diagnostic effect on PMOP. After Dex treatment, the expressions of miR-361-5p, VEGFA, BMD related indexes were increased in OP rats. In BMSCs, level of osteogenesis-angiogenesis related genes were increased after adding Dex, and the apoptosis was decreased after coculture of HUVECs and BMSCs. miR-361-5p could target VEGFA. After miR-361-5p overexpression + Dex treatment, the indexes related to osteogenesis and angiogenesis in OP rats and BMSCs were decreased, which were reversed after further overexpressing VEGFA. SIGNIFICANCE: Dex can enhance VEGFA by inhibiting miR-361-5p, and then promote osteogenesis-angiogenesis, thus providing potential targets for PMOP treatment.


Assuntos
Dexmedetomidina/farmacologia , MicroRNAs/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteoporose Pós-Menopausa/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/metabolismo , Idoso , Animais , Densidade Óssea , Dexmedetomidina/uso terapêutico , Feminino , Citometria de Fluxo , Humanos , MicroRNAs/fisiologia , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Osteoporose Pós-Menopausa/fisiopatologia , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Fator A de Crescimento do Endotélio Vascular/fisiologia
14.
Carbohydr Polym ; 251: 117116, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142651

RESUMO

Previous studies have suggested that water-soluble polysaccharides from fermented carrot pulp (WSP-p) have stronger anti-diabetic effects than those from un-fermented carrot pulp (WSP-n). This study aimed to improve understanding of these functional differences by comparing their molecular structures. Weight-average molecular weights of WSP-p fractions were lower than those of the corresponding WSP-n fractions. While both WSPs had similar functional groups, more fragmented particles were observed on the surface of large particles of WSP-n than WSP-p. Monosaccharide composition and methylation analysis confirmed that both WSP-p and WSP-n were pectic polysaccharides, containing rhamnogalacturonan-I-type polysaccharides with 1,4-linked α-d-galacturonic acid residues and homogalacturonan regions with 1,4-GalpA linkages. 1H and 13C NMR showed that they had similar linkage patterns. These findings suggested that probiotic fermentation of WSP mainly cleaved the linkages between repeating units, and resulted in less polydisperse molecular size distributions.


Assuntos
Daucus carota/química , Polissacarídeos/química , Probióticos/metabolismo , Daucus carota/metabolismo , Fermentação , Ácidos Hexurônicos/química , Ácidos Hexurônicos/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular , Monossacarídeos/química , Monossacarídeos/metabolismo , Polissacarídeos/metabolismo , Probióticos/química
15.
ACS Appl Mater Interfaces ; 12(49): 54387-54398, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33236873

RESUMO

In situ glyco-editing on the cell surface can endow cellular glycoforms with new structures and properties; however, the lack of cell specificity and dependence on cells' endogenous functions plague the revelation of cellular glycan recognition properties and hamper the application of glyco-editing in complicated authentic biosystems. Herein, we develop a thermally triggered, cell-specific glyco-editing method for regulation of lectin recognition on target live cells in both single- and cocultured settings. The method relies on the aptamer-mediated anchoring of microgel-encapsulated neuraminidase on target cells and subsequent thermally triggered enzyme release for localized sialic acid (Sia) trimming. This temperature-based enzyme accessibility modulation strategy exempts genetic or metabolic engineering operations and, thus for the first time, enables tumor-specific desialylation on complicated tissue slices. The proposed method also provides an unprecedented opportunity to potentiate the innate immune response of natural killer cells toward target tumor cells through thermally triggered cell-specific desialylation, which paves the way for in vivo glycoimmune-checkpoint-targeted cancer therapeutic intervention.


Assuntos
Materiais Biocompatíveis/metabolismo , Imunidade Celular , Lectinas/metabolismo , Neuraminidase/metabolismo , Animais , Aptâmeros de Nucleotídeos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Géis/química , Humanos , Células Matadoras Naturais/imunologia , Lectinas/química , Camundongos , Camundongos Nus , Ácido N-Acetilneuramínico/metabolismo , Neuraminidase/química , Tamanho da Partícula , Ligação Proteica , Temperatura , Transplante Heterólogo
16.
Genomics ; 112(6): 4399-4405, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32738269

RESUMO

PURPOSE: Genetic polymorphisms act a crucial role in chronic obstructive pulmonary disease (COPD) progression. This study aimed to investigate the correlation between CYP3A4 variants and COPD risk. METHODS: We carried out a case-control study of 821 individuals (313 patients and 508 healthy subjects) to identify the correlation of CYP3A4 SNPs with COPD risk in the Hainan Han population. The association was evaluated by Odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Our study showed that rs4646437 polymorphism was related to a significantly increased susceptibility to COPD (OR 1.45, 95% CI = 1.10-1.90, p = 0.008). Stratified analyses indicated that rs4646437 polymorphism was significantly related to an increased risk of COPD in males (OR 1.95, 95% CI = 1.19-3.20, p = 0.008). However, rs4646440 played a protective role in females (OR 0.54, 95% CI = 0.31-0.93, p = 0.024). Rs4646437 was found to significantly improve the risk of COPD in smokers (OR 1.67, 95% CI = 1.12-2.48, p = 0.011). While rs4646440 had a significantly lower susceptibility to COPD in non-smokers (OR 0.64, 95% CI = 0.45-0.90, p = 0.010). Haplotype analysis revealed that Ars4646440Trs35564277 haplotype of CYP3A4 was found to increase the risk of COPD in non-smokers (OR 1.71, 95% CI = 1.04-2.82, p = 0.034). CONCLUSION: Our result gives a new understanding of the association between CYP3A4 gene and COPD in the Hainan Han population.


Assuntos
Citocromo P-450 CYP3A/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Doença Pulmonar Obstrutiva Crônica/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , China/etnologia , Feminino , Frequência do Gene , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/etnologia , Fumar
17.
J Phys Chem Lett ; 11(15): 6191-6200, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32635734

RESUMO

Dynamic room-temperature phosphorescence (RTP) in organic materials is highly sensitive toward changes of external stimulus, representing the expansion of static RTP materials with fixed properties, and has gradually captured considerable attention. Different from the big breakthroughs in static organic RTP materials, dynamic organic RTP materials remain a clear improvement over luminescent mechanisms and molecular design rule. Therefore, we have reviewed the progress of organic RTP materials from static to dynamic phosphorescence and provide insight into the dynamic behaviors of RTP lifetime, color, intensity, and efficiency under different external stimuli, especially changes to the excitation source, such as irradiation time, intensity, and excitation wavelengths. Subsequently, we present some viewpoints on this promising field to strengthen the understanding of dynamic RTP characteristics. This Perspective may be beneficial for the future development of smart materials with dynamic RTP.

18.
Chem Asian J ; 15(7): 947-957, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32031734

RESUMO

Organic room temperature phosphorescence (RTP) materials have drawn increasing attention due to their unique features, especially the long emission lifetime for applications in biomedicine. In this review, we provide an overview of the recent developments of organic RTP materials applied in the biomedicine field. First, we introduce the basic mechanism of phosphorescence and subsequently we present various strategies of modulating the lifetime and efficiency of room temperature organic phosphorescence. Next, we summarize the progress of organic RTP materials in biological applications, including bioimaging, anti-cancer and antibacterial therapies. Finally, we provide an outlook with regard to the challenges and future perspectives in the field.


Assuntos
Substâncias Luminescentes/farmacologia , Medições Luminescentes/métodos , Temperatura , Animais , Antibacterianos/química , Antibacterianos/uso terapêutico , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Diagnóstico por Imagem/métodos , Humanos , Luminescência , Substâncias Luminescentes/uso terapêutico
19.
Small ; 16(8): e1906733, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32003926

RESUMO

Ultralong organic phosphorescence (UOP), enabling of persistent luminescence after removal of external excitation light, shows great promise in biological applications such as bioimaging in virtue of antibackground fluorescence interference. Despite of good biocompatibility and outstanding phosphorescent properties, most current organic phosphors are hydrophobic with poor water solubility in the form of bulk crystal with large size, limiting their potential in the biological field. Here, a facile and versatile approach is provided to obtain nanoscale hydrophilic phosphorescent phosphors (HPPs) by physically loading ultralong organic phosphors into hollow mesoporous silica nanoparticles. The as-prepared HPPs can be well suspended in aqueous solution and effectively internalized by HeLa cells with very low cytotoxicity. Such HPPs are successfully applied for afterglow bioimaging in living nude mice with a very high signal-to-noise ratio up to 31. The current study not only provides a universal strategy to realize UOP in aqueous media but also demonstrates their great potential for biomedical purposes as an advanced imaging indicator with long-lived emission lifetime.


Assuntos
Diagnóstico por Imagem , Nanopartículas , Dióxido de Silício , Animais , Diagnóstico por Imagem/métodos , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Luminescência , Camundongos , Camundongos Nus , Nanopartículas/química , Nanopartículas/metabolismo , Dióxido de Silício/química
20.
Research (Wash D C) ; 2020: 8183450, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32110780

RESUMO

Developing ultralong organic phosphorescence (UOP) materials with smart response to external stimuli is of great interest in photonics applications, whereas the manipulation of molecular stacking on tuning such dynamic UOP is still a formidable challenge. Herein, we have reported two polymorphs with distinct photoactivated dynamic UOP behavior based on a pyridine derivative for the first time. Our experiment revealed that the dynamic UOP behavior including photoactivation and deactivation feature is highly dependent on irradiation intensity and environmental atmosphere. Additionally, given the unique dynamic UOP feature, these phosphors have been successfully applied to phosphorescence-dependent molecular logic gate and timing data storage. This result not only paves a way to design smart functional materials but also expands the scope of the applications on organic phosphorescence materials.

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