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1.
Angew Chem Int Ed Engl ; 63(13): e202315122, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38311601

RESUMEN

Dendrites growth and unstable interfacial Li+ transport hinder the practical application of lithium metal batteries (LMBs). Herein, we report an active layer of 2,4,6-trihydroxy benzene sulfonyl fluorine on copper substrate that induces oriented Li+ deposition and generates highly crystalline solid-electrolyte interphase (SEI) to achieve high-performance LMBs. The lithiophilic -SO2 - groups of highly crystalline SEI accept the rapidly transported Li+ ions and form a dense inner layer of LiF and Li3 N, which regulate Li+ plating morphology along the (110) crystal surface toward dendrite-free Li anode. Thus, Li||Cu cells with lithiophilic SEI achieve an average deposition efficiency of 99.8 % after 700 cycles, and Li||Li cells operate well for 1100 h. Besides, Li||LiNi0.8 Co0.1 Mn0.1 O2 cells with modified SEI exhibit a capacity retention that is 14 times than that of conventional SEI. Even at -60 °C, Li||Cu cells reach stable deposition efficiency of 83.2 % after 100 cycles.

2.
Anal Chem ; 95(9): 4503-4512, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36812425

RESUMEN

An ultrasensitivity detecting assay for acetylcholinesterase (AChE) activity was developed based on "covalent assembly" and signal amplification strategic approaches. After hydrolyzing thioacetylcholine by AChE and participation of thiol in a self-inducing cascade accelerated by the Meldrum acid derivatives of 2-[bis(methylthio) methylene] malonitrile (CA-2), mercaptans triggered an intramolecular cyclization assembly by the probe of 2-(2,2-dicyanovinyl)-5-(diethylamino) phenyl 2,4-dinitrobenzenesulfonate (Sd-I) to produce strong fluorescence. The limit of detection for AChE activity was as low as 0.0048 mU/mL. The detection system also had a good detecting effect on AChE activity in human serum and could also be used to screen its inhibitors. By constructing a Sd-I@agarose hydrogel with a smartphone, a point-of-care detection of AChE activity was achieved again.


Asunto(s)
Acetilcolinesterasa , Compuestos de Sulfhidrilo , Humanos , Fluorescencia , Inhibidores de la Colinesterasa/farmacología
3.
Anal Chem ; 95(27): 10376-10383, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37358141

RESUMEN

In this work, two nanometal-organic frameworks (NMOFs) of ZIF-8-1 and ZIF-8-2 were designed and synthesized with a "missing linker" defects strategy by using Oxime-1 and Oxime-2 as coligands, respectively. ZIF-8-2 exhibited an excellent performance in comparison to that of ZIF-8-1 in activating and regenerating the activity of BChE suppressed by demeton-S-methyl (DSM) and could rapidly detoxify DSM in poisoned serum samples within 24 min. Additionally, the synthesized fluorescence probe of IND-BChE with high quantum yields, large Stokes shifts, and superior water solubility could be used for the detection of both butyrylcholinesterase (BChE) and DSM in a lower LOD of 0.63 mU/mL (BChE) and 0.086 µg/mL (DSM). By the difference in fluorescent intensity of IND-BChE with and without ZIF-8-2, a highly linear relationship of IND-BChE with DSM concentration was found (R2 = 0.9889), and the LOD was 0.073 µg/mL. In addition, an intelligent detection platform of ZIF-8-2@IND-BChE@agarose hydrogel combined with a smartphone formed a point-of-care test for DSM -poisoned serum samples and also realized satisfactory results. Unlike other detection methods of nerve agents, this assay first combined an NMOF reactivator for detoxification and detection of BChE enzyme activity and then quantification of OP nerve agents, which was of great significance in treatment of organophosphate poisoning.


Asunto(s)
Nanopartículas , Agentes Nerviosos , Butirilcolinesterasa , Oximas , Organofosfatos , Activación Enzimática
4.
Drug Dev Ind Pharm ; 47(11): 1744-1752, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35193436

RESUMEN

Melanoma accounts for the highest proportion of all skin cancer deaths. Immune-chemotherapy has transformed anti-melanoma therapy and is a preferred first-line combination strategy for melanoma. We previously prepared dendritic cells (DCs) targeting the nanocomplex paclitaxel (PTX)-encapsulated sulfobutylether-ß-cyclodextrin (SBE)/mannosylated N,N,N-trimethyl chitosan (mTMC)/DNA (PTX/SBE-DNA/Man-TMC) for the co-delivery of pTRP-2 DNA and adjuvant PTX. The nanocomplex PTX/SBE-DNA/Man-TMC promoted DC maturation and antigen presentation and spur potent anti-melanoma immunity. However, the mechanism by which PTX/SBE-DNA/Man-TMC regulates the biological functions of DCs and T lymphocytes is unknown. Therefore, we explored the underlying signaling pathways and mixed leukocyte reactions, resulting in enhanced T cell-mediated anti-tumor immunity. Interleukin-12 secretion from nanocomplex-pulsed mouse bone marrow-derived DCs was inhibited by treatment with Toll-like receptor 4 (TLR-4), nuclear factor kappa-B (NF-κB), and a specific blocker of p38 mitogen-activated protein kinase (MAPK). The results revealed that TLR-4, NF-κB, and MAPK signaling pathways were essential anti-tumor immune responses regulation factors. Furthermore, mixed leukocytes pulsed with PTX/SBE-DNA/Man-TMC induced tumor cell apoptosis and arrested the cell cycle in G0/G1, significantly promoting the synergy. Thus, we concluded that the mechanism driving the PTX/SBE-DNA/Man-TMC immune-chemotherapy synergistic effect was multifactorial.


Asunto(s)
Melanoma , Paclitaxel , Adyuvantes Inmunológicos/farmacología , Animales , Humanos , Melanoma/tratamiento farmacológico , Ratones , FN-kappa B/metabolismo , Paclitaxel/farmacología , Receptor Toll-Like 4
5.
Anal Chem ; 91(17): 10979-10983, 2019 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-31373196

RESUMEN

The highly selective and sensitive fluorescence "light-up" probe, 5'-(dimethylamino)-2'-formyl-N-hydroxy-[1,1'-biphenyl]-2-carboxamide(PTS), has been fabricated for the nerve-agent mimic diethyl chlorophosphate (DCP). The probe is designed by combining two novel strategies of "covalent assembly" and Lossen rearrangement. Formation of a phosphoryl intermediate from DCP and a hydroxamic acid group in PTS yields an isocyanate that quickly undergoes Lossen rearrangement to produce an aniline that condenses intramolecularly to a fluorescent phenanthridine system. PTS shows superior properties to probe DCP, such as rapid response (within 100 s), low detection limit (10.4 nM), specificity, and excellent linearity (R2 = 0.9993) in the range from 2 to 16 µM. More importantly, its application of detecting DCP vapor has also been achieved with satisfying results.


Asunto(s)
Compuestos de Bifenilo/química , Sustancias para la Guerra Química/análisis , Colorantes Fluorescentes/química , Compuestos Organofosforados/análisis , Espectrometría de Fluorescencia/métodos , Compuestos de Anilina/química , Humanos , Isocianatos/química , Cinética , Límite de Detección , Imitación Molecular , Organofosfatos/análisis , Fenantridinas/química , Sarín/análisis , Soman/análisis
6.
Small ; 13(28)2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28561892

RESUMEN

This work aims at developing an immunotherapeutic strategy to deliver a cancer DNA vaccine targeting dendritic cells (DCs), to trigger their maturation and antitumor function, and reduce immune escape using a polymeric nanocomplex of paclitaxel (PTX)-encapsulated sulfobutylether-ß-cyclodextrin (SBE)/mannosylated N,N,N-trimethylchitosan (mTMC)/DNA. To enhance DC-targeting and revoke immunosuppression is the major challenge for eliciting effective antitumor immunity. This codelivery system is characterized by using low-dose PTX as an adjuvant that is included inside SBE, and the PTX/SBE further serves as an anionic crosslinker to self-assemble with the cationic mTMC/DNA polyplexes. This system is used in combination with a microneedle for transcutaneous vaccination. Once penetrating into the epidermis, the mannosylated nanocomplexes would preferentially deliver the pTRP-2 DNA vaccine inside the DCs. Phenotypic maturation is demonstrated by the increased expression of costimulatory molecules of CD80 and CD86, and the elevated secretion of IL-12p70. The mixed leucocyte reactions reveal that the PTX/SBE-mTMC/DNA nanocomplexes enhance the proliferation of CD4+ and CD8+ T cells, and inhibit the generation of immune-suppressive FoxP3+ T cells. The system shows high antitumor efficacy in vivo. The PTX/SBE-mTMC/DNA nanocomplexes for DC-targeted codelivery of DNA vaccine and adjuvant PTX yield synergistic effects on the DC maturation and its presenting functions, thus increasing immune stimulation and reducing immune escape.


Asunto(s)
Inmunoterapia/métodos , Paclitaxel/farmacología , Animales , Vacunas contra el Cáncer , Diferenciación Celular/efectos de los fármacos , Células Dendríticas/efectos de los fármacos , Humanos , Paclitaxel/administración & dosificación
7.
Org Biomol Chem ; 15(5): 1072-1075, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28059419

RESUMEN

We report a fluorescent probe for the selective detection of mitochondrial glutathione (GSH). The probe, containing triphenylphosphine as a mitochondrial targeting group, exhibited ratiometric and selective detection of GSH over Cys/Hcy. The probe was used for imaging mitochondrial GSH in living HeLa cells.


Asunto(s)
Colorantes Fluorescentes/química , Glutatión/análisis , Mitocondrias/química , Colorantes Fluorescentes/análisis , Colorantes Fluorescentes/síntesis química , Células HeLa , Humanos , Estructura Molecular
8.
J Hazard Mater ; 465: 133326, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38150765

RESUMEN

In this paper, a novel All-In-One Urea@MIL-100(Fe)/CI-MCC/SA hydrogel platform was generated by microcrystalline cellulose (MCC) functionalized with pH-response probe (CI), MIL-100 (Fe) and sodium alginate (SA), which was as a carrier of urea to adsorb, remove and monitor NO2-. Under acidic condition, the fluorescent hydrogel platform could produce N2, CO2 and H2O through the diazotization and redox reaction between urea and NO2- with a removal efficiency up to 99.8%, and could also character a good adsorption property for NO2- due to the positive charges of protonation (the maximum adsorption capacity was 21.67 mg g-1), and the adsorption kinetics conformed to pseudo-second-order model. By carried out the NO2- removal step in fluorescent hydrogel platform, NO2- could also be detected indirectly by sensing the changes of pH within 15 min. The linear response range was 0-0.005 M, and the detection limit (LOD) was 74 µM. These results demonstrated that this All-In-One Urea@MIL-100(Fe)/CI-MCC/SA hydrogel platform had great potential in environment. This strategy for the removal and monitoring of NO2- could be employed to related applications in water purification and environmental protection. ENVIRONMENTAL IMPLICATION: Nitrite is one of the important indicators of water monitoring, which is harmful to human and environment. The removal and monitoring of nitrite in industrial wastewater and surface water is very important, but there are no studies about it at present. Based on the fact that urea can react with nitrite to produce green products, we synthesized a novel functional hydrogel to achieve adsorption, removal and fluorescence monitoring of nitrite for the first time. Besides, the practicability of the material in environmental water samples was verified through the detection of nitrite in simulated wastewater.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 321: 124661, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38909562

RESUMEN

A ratiometric fluorescent and colorimetric detecting assay for NO2- was realized by a hybrid nanosensor (Co2+-CDs@R-CDs) utilizing firstly through the redox reaction of nitrite (NO2-) with Co2+, of which the hybrid nanosensor Co2+-CDs@R-CDs was fabricated by Co2+-doped carbon dots (Co2+-CDs) and a reference of red-emitting carbon dots (R-CDs). The ratiometric fluorescent linear detection range of NO2- was 2.5-45 µM and the limit of detection (LOD) was 0.068 µM with the response time of 120 s. While, the colorimetric linear detection range of NO2- was 2.5-60 µM and the LOD was 0.075 µM. In addition, a portable smartphone system which could measure the R (red), G (green), and B (blue) values of the fluorescence and the visible color of the coated Co2+-CDs@R-CDs paper strip-based sensor had also been developed and successfully applied to detect NO2- in sausage, pickles and tap water samples.

10.
J Dent ; 142: 104866, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38281620

RESUMEN

OBJECTIVES: Fatigue and low-temperature degradation (LTD) are the main factors contributing to zirconia restoration failure. This study evaluated the effect of LTD on the fatigue performance of the novel "strength & shade-gradient" multilayered zirconia restorations. METHODS: Discs (15 mm × 1.2 mm) of each yttria content layer from a newly developed strength-gradient multilayered zirconia were fabricated and under accelerated aging in an autoclave at 134℃ for 0 h, 32 h, and 64 h. Then, the phase transformation, microstructure, and mechanical properties after LTD were assessed. In addition, the crown samples, including the multi-Zir, 3Y-Zir, and 5Y-Zir were fabricated, and their monotonic and fatigue load before and after LTD, percentage of fatigue degradation (Sd) and the fracture morphology were investigated. Statistical analyses were performed using paired samples t-test (α' = α/3 = 0.017), one-way ANOVA and Weibull analysis. RESULTS: After LTD, the phase transformation, surface roughness, depth of transformed zone, and residual stress were increased and inversely associated with the yttria content. The indentation elastic modulus and hardness after LTD decreased; however, there was no significant difference between the different yttria content layers. The monotonic and fatigue load of multi-Zir restorations decreased, but their Weibull modulus increased, and Sd decreased, similar to 3Y-Zir. The crack origin was associated with the cervical region. CONCLUSION: These results show that although LTD reduces the absolute fatigue strength of strength-gradient multilayered zirconia restorations, it also reduces the effect of cyclic fatigue itself on the strength of zirconia (relative to monotonic strength), which might be due to the increase of residual stress. CLINICAL SIGNIFICANCE: The novel "strength & shade-gradient" multilayered zirconia restorations show a promising performance during in vitro LTD and fatigue test and their reliability to some extent is comparable to 3Y-Zir. Yet, further in vivo longitudinal studies are warranted to confirm their precise performance.


Asunto(s)
Materiales Dentales , Itrio , Materiales Dentales/química , Ensayo de Materiales , Temperatura , Reproducibilidad de los Resultados , Itrio/química , Circonio/química , Propiedades de Superficie , Cerámica
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(4): 1092-7, 2013 Apr.
Artículo en Zh | MEDLINE | ID: mdl-23841435

RESUMEN

A 6',8'-di-tert-butyl-1-hydroxyethyl-3,3-dimethyl-indoline benzospiropyran L1 and its derivative L2 were synthesized and characterized. Chelation-enhanced appearswhen L1 with electron donating groups of 6', 8'-di-tert-butyl touch on benzospiropyran and affect the stability of cyanine structure. L1 exhibited high selectivity to Hg2+, Cr3+, Ag+ over other metal ions. While, there was no obvious interferences of coexist metal ions on Hg2+, Cr3+, Ag+ detection. The Hg2+, Cr+, Ag+ recognition of L1 not only could be achieved by means of fluorescense and absorption "turn-on" spectra but also an obvious color change from colorless to yellowish by naked-eyes. The binding of L1 to Ag+, Cr3+, Hg2+ are in 1 : 1 stoichometry and the detection limits are 7.435 8 x 10(-6), 6.126 8 x 10(-6), 3.452 4 x 10(-6) mol x L(-1). The sensing mechanism was also investigated from L2.

12.
Anal Chim Acta ; 1263: 341280, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37225329

RESUMEN

The nitration reaction of nitrite and phenolic substances was first used to identify and detect NO2- by taking fluorescent poly (tannic acid) nanoparticles (FPTA NPs) as sensing platform. With the low cost, good biodegradable and convenient water-soluble FPTA NPs, a fluorescent and colorimetric dual modes detecting assay was realized. In fluorescent mode, the linear detection range of NO2- was 0-36 µM, the LOD was as low as 3.03 nM, and the response time was 90 s. In colorimetric mode, the linear detection range of NO2- was 0-46 µM, and the LOD was as low as 27 nM. Besides, a smartphone with FPTA NPs@ agarose hydrogel formed a portable detection platform to test the fluorescent and visible color changes of FPTA NPs for NO2- sensing as well as for accurate visualization and quantitative detection of NO2- in actual water and food samples.


Asunto(s)
Nanopartículas , Nitritos , Colorimetría , Dióxido de Nitrógeno , Taninos , Colorantes
13.
RSC Adv ; 11(54): 34291-34299, 2021 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-35497289

RESUMEN

As one kind of reactive carbonyl species (RCS), formaldehyde (FA) with a high concentration could be extremely toxic to living bodies as well as the environment. This paper reports a three-dimensional (3D) Tb3+@Ag-MOFs-based fluorescent probe for fast sensing of FA, which uses a novel turn-on mechanism based on the luminescence induced by Tb3+. The MOF sensor shows broad dynamic ranges of 0.1-1 mM for FA with the detection limit of 1.9 µM. For online and real-time detection of FA, a portable smartphone platform was employed to analyze the RGB values of the fluorescence by a smartphone application. By incorporating this probe into a polyacrylonitrile (PAN) layer, we synthesized a film composite that could effectively remove FA in real samples including milk and chemical factory wastewater, and the removal rate reached 98.52% and 95.38% respectively. Moreover, the potential of the film to remove gaseous FA was confirmed by experiments as well.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(5): 1386-90, 2010 May.
Artículo en Zh | MEDLINE | ID: mdl-20672639

RESUMEN

Five kinds of Salen Mn(II) and two kinds of Eu(III) complexes were synthesized. Under the system of NBT/L-methionine, which creates and detects O2*-, the complexes of antioxidant activity were studied, and the conclusion revealed that all Mn(II) complexes have obvious antioxidant activity. The fluorescence study indicated that all the Salen metal complexes could bind with DNA, which shows their potential anticancer activity.


Asunto(s)
Antioxidantes/química , ADN/química , Europio/química , Compuestos Organometálicos/química , Análisis Espectral , Antineoplásicos/química , Complejos de Coordinación , Oxidación-Reducción
15.
Int J Nanomedicine ; 15: 5855-5871, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32848394

RESUMEN

PURPOSE: Osteomyelitis, particularly chronic osteomyelitis, remains a major challenge for orthopedic surgeons. The traditional treatment for osteomyelitis, which involves antibiotics and debridement, does not provide a complete solution for infection and bone repair. Antibiotics such as vancomycin (VCM) are commonly used to treat osteomyelitis in clinical settings. VCM use is limited by a lack of effective delivery methods that provide sustained, high doses to entirely fill irregular bone tissue to treat infections. METHODS: We engineered a chitosan (CS)-based thermosensitive hydrogel to produce a VCM-nanoparticle (NPs)/Gel local drug delivery system. The VCM-NPs were formed with quaternary ammonium chitosan and carboxylated chitosan nanoparticles (VCM-NPs) by positive and negative charge adsorption to enhance the encapsulation efficiency and drug loading of VCM, with the aim of simultaneously preventing infection and repairing broken bones. This hydrogel was evaluated in a rabbit osteomyelitis model. RESULTS: The VCM-NPs had high encapsulation efficiency and drug loading, with values of 60.1±2.1% and 24.1±0.84%, respectively. When embedded in CS-Gel, the VCM-NPs maintained their particle size and morphology, and the injectability and thermosensitivity of the hydrogel, which were evaluated by injectability test and rheological measurement, were retained. The VCM-NPs/Gel exhibited sustained release of VCM over 26 days. In vitro tests revealed that the VCM-NPs/Gel promoted osteoblast proliferation and activity against Staphylococcus aureus. In vivo, VCM-NPs/Gel (with 10 mg vancomycin per rabbit) was used to treat rabbits with osteomyelitis. The VCM-NPs/Gel showed excellent anti-infection properties and accelerating bone repair under osteomyelitis conditions. CONCLUSION: The reported multifunctional NPs hydrogel system for local antibiotic delivery (VCM-NPs/Gel) showed bone regeneration promotion and anti-infection properties, demonstrating significant potential as a scaffold for effective treatment of osteomyelitis.


Asunto(s)
Antibacterianos/administración & dosificación , Hidrogeles/química , Nanopartículas/administración & dosificación , Osteomielitis/tratamiento farmacológico , Vancomicina/administración & dosificación , Animales , Antibacterianos/farmacocinética , Proliferación Celular/efectos de los fármacos , Quitosano/química , Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Hidrogeles/administración & dosificación , Hidrogeles/farmacología , Inyecciones , Masculino , Nanopartículas/química , Osteoblastos/efectos de los fármacos , Osteoblastos/microbiología , Tamaño de la Partícula , Conejos , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos , Vancomicina/farmacocinética
16.
RSC Adv ; 9(70): 40873-40882, 2019 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-35540044

RESUMEN

Chemotherapeutic drug resistance poses a great challenge in cancer therapy. Drug efflux and anti-apoptotic processes are the two most common mechanisms leading to chemotherapy resistance. In this study, we focused on the applicability of curcumin (CUR) as a sensitizer for chemotherapeutics (doxorubicin [DOX] as the model drug) modified with hyaluronic acid (HA) as an effective therapeutic strategy against multidrug resistance (MDR) in cancer cells. We constructed an HA-CUR/DOX delivery system measuring approximately 180 nm with superior encapsulation efficacy and serum stabilities. In vitro, we found that HA modification could facilitate the efficient delivery of chemotherapeutics through CD44 receptor-mediated targeted delivery. MTT assay results confirmed that the combination of CUR and DOX/paclitaxel (PTX) had a significant synergistic effect and significantly reversed MDR. Further experiments including real-time polymerase chain reaction and western blotting proved that the main mechanisms by which CUR reversed MDR in tumor cells were inhibiting the expression and activity of P-glycoprotein (P-gp) and inducing apoptosis through mitochondrial pathway. Taken together, our new engineered tumor-targeting nanoparticle delivery system may have the potential for overcoming MDR in cancer.

17.
Anal Chim Acta ; 1030: 172-182, 2018 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-30032767

RESUMEN

A highly selective fluorescent probe (SiROPS) based on Si-rhodamine (SiR) towards F- was investigated. SiROPS can realize the NIR detection of F- because of the long fluorescent wavelength (λex = 650 nm, λem = 669 nm). The near-IR optical and the ratiometric fluorescence type signaling were realized by employing fluoride-selective cleavage of the latent thiophosphinated probe in mixed aqueous media. The cleavage of F- to the ortho positions of dimethylphosphinothionyl group in the meso aryl involves the suppression of internal rotation upon phosphorylation of a reactive phenolate and the activating rotation of o-OH, which resulting in a large fluorescence "Turn-Off" response. The detection limit of the probe to F- was 48 nM in the dynamic range of 0.5 µM-20 µM. In addition, the proposed probe has been used to detect F- in water samples and toothpaste samples with satisfying results.


Asunto(s)
Colorantes Fluorescentes/química , Fluoruros/análisis , Compuestos de Organosilicio/química , Rodaminas/química , Colorantes Fluorescentes/síntesis química , Rayos Infrarrojos , Iones/análisis , Estructura Molecular , Compuestos de Organosilicio/síntesis química
18.
RSC Adv ; 8(57): 32497-32505, 2018 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-35547726

RESUMEN

Based on the fluorophore of 2-(2'-hydroxyphenyl)benzothiazole (HBT) with aggregation-induced emission (AIE) properties, a highly selective and sensitive fluorescent probe PBT towards F- was investigated. "Turn-On" fluorescence type signaling was realized by employing fluoride-selective cleavage of the latent thiophosphinated probe in mixed aqueous media. The probe is designed in such a way that the excited state intramolecular proton transfer (ESIPT) of the HBT moiety becomes blocked. The chemodosimetric approach of F- to the probe results in the recovery of the ESIPT by removal of a free AIE-active HBT moiety through a subsequent hydrolysis process. The F- detection limit of the probe was 3.8 nM in the dynamic range of 0.5 µM to 10 µM. In addition, the proposed probe has been used to detect F- in water samples and toothpaste samples with satisfying results.

19.
Biosens Bioelectron ; 90: 403-409, 2017 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-27825881

RESUMEN

Glutathione (GSH) and cysteine (Cys) play different roles in biological systems, thus the discrimination between them is of great importance. Herein we report a multi-emissive fluorescent probe for the selective detection of GSH and Cys. The probe was composed of covalently linked BODIPY and coumarin fluorophores. The BODIPY fluorophore was designed to react with GSH and Cys and generate different products with distinct photophysical properties, and the coumarin fluorophore acted as an internal standard. The probe exhibited green emission in aqueous solution. Upon addition of Cys, it yielded nitrogen-substituted BODIPY with weak fluorescence and free coumarin with blue emission. In the presence of glutathione, it generated mono- and di-sulfur substituted BODIPY and coumarin, resulting in various emission colors at different concentrations of GSH. Interestingly, the solution exhibited white fluorescence at GSH concentration of 0.4mM. The probe was capable of detecting and imaging GSH and Cys in living HeLa cells, indicating its significant potential in biological applications.


Asunto(s)
Técnicas Biosensibles , Cisteína/aislamiento & purificación , Colorantes Fluorescentes/química , Glutatión/aislamiento & purificación , Compuestos de Boro/química , Cumarinas/química , Cisteína/química , Glutatión/química , Células HeLa , Humanos
20.
Adv Mater ; 29(40)2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28859234

RESUMEN

Suppression of carrier recombination is critically important in realizing high-efficiency polymer solar cells. Herein, it is demonstrated difluoro-substitution of thiophene conjugated side chain on donor polymer can suppress triplet formation for reducing carrier recombination. A new medium bandgap 2D-conjugated D-A copolymer J91 is designed and synthesized with bi(alkyl-difluorothienyl)-benzodithiophene as donor unit and fluorobenzotriazole as acceptor unit, for taking the advantages of the synergistic fluorination on the backbone and thiophene side chain. J91 demonstrates enhanced absorption, low-lying highest occupied molecular orbital energy level, and higher hole mobility, in comparison with its control polymer J52 without fluorination on the thiophene side chains. The transient absorption spectra indicate that J91 can suppress the triplet formation in its blend film with n-type organic semiconductor acceptor m-ITIC (3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone)-5,5,11,11-tetrakis(3-hexylphenyl)-dithieno[2,3-d:2,3'-d']-s-indaceno[1,2-b:5,6-b']-dithiophene). With these favorable properties, a higher power conversion efficiency of 11.63% with high VOC of 0.984 V and high JSC of 18.03 mA cm-2 is obtained for the polymer solar cells based on J91/m-ITIC with thermal annealing. The improved photovoltaic performance by thermal annealing is explained from the morphology change upon thermal annealing as revealed by photoinduced force microscopy. The results indicate that side chain engineering can provide a new solution to suppress carrier recombination toward high efficiency, thus deserves further attention.

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