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1.
Biosensors (Basel) ; 14(6)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38920616

RESUMO

Optical sensors, especially fluorescence sensors, have been widely used because of their advantages in sensing, such as the high sensitivity, good selectivity, no radiation source, and easy operation. Here, we report an example of fluorescence sensing based on two-dimensional (2D) covalent organic polymers and highlight that the material can achieve a fast response and multi-signal output. This 2DPTPAK+TAPB-based sensor can quickly detect aromatic hydrocarbons and Fe3+ by the fluorescence signal or electrical resistance signal.


Assuntos
Polímeros , Polímeros/química , Técnicas Biossensoriais , Hidrocarbonetos Aromáticos/análise , Corantes Fluorescentes , Espectrometria de Fluorescência
2.
Adv Mater ; : e2406256, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38897184

RESUMO

Synthesizing uniform functional covalent organic framework (COF) microspheres is the prerequisite of applying COFs as novel stationary phases for liquid chromatography. However, the synthesis of functionalized COF microspheres is challenging due to the difficulty in maintaining microspheric morphology when conferring functions. Here, a facile and universal "self-limited dynamic linker exchange" strategy is developed to achieve surface functionalization of uniform COF microspheres. Six different types of COF microspheres are constructed, showing the universality and superiority of the strategy. The library of COF microspheres' stationary phases can be further enriched on demand by varying different functional building blocks. The "self-limited dynamic linker exchange" is attributed to the result of a delicate balance of reaction thermodynamics and molecular diffusion energy barrier. As a demonstration, the chiral functional COF microspheres are used as stationary phases of chiral chromatography and realized effective enantioseparation.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37919250

RESUMO

Biomimic mineralization of hard tissues with hierarchical structures is a challenging task, while designing multifunctional materials possessing both the ability of biomimic mineralization and drug delivery is even more difficult. Herein, inspired by the multilevel structure and mineralization ability of amelogenin, a novel carboxyl-functionalized covalent organic framework (COF) nanosphere material was designed and synthesized, which exhibited a significant biomimetic remineralization ability as demonstrated on SiO2 glass, Ti6Al4V, and an acid-etched enamel surface. Furthermore, the nanoporous structure also enables the COF nanospheres to serve as a drug delivery system for the controlled release of antibacterial drugs. This work provides a promising strategy for the design of multifunctional biomimic materials.

4.
Nat Commun ; 14(1): 6049, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770448

RESUMO

The topology type and the functionalization of pores play an important role in regulating the performance of covalent organic frameworks. Herein, we designed and synthesized the covalent organic framework with hetero-environmental pores using predesigned asymmetrical dialdehyde monomer. According to the results of structural characterization, crystallinity investigation, and theoretical calculation, the hetero-environmental pores of the obtained framework are regarded as the alternant arrangement. The distinctive hetero pore structure leads the designed material to show more advantages as compared with control materials in loading both hydrophobic and hydrophilic antibiotics for wound healing. This dual-antibiotic strategy can expand the antibacterial range as compared with the single antibiotic one, and reduce the generation of drug resistance. In summary, this strategy for designing covalent organic frameworks with hetero-environmental pores can extend the structural variety and provide a pathway for improving the practical application performance of these materials.


Assuntos
Estruturas Metalorgânicas , Antibacterianos/farmacologia , Cicatrização
5.
Angew Chem Int Ed Engl ; 62(18): e202300532, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-36737406

RESUMO

Bimetallic electrocatalysts with its superior performance has a broad application prospect in oxygen evolution reaction (OER), but the fundamental understanding of the mechanism of synergistic effect is still limited since there lacks a practical way to decouple the influence factors on the intrinsic activity of active sites from others. Herein, a series of bimetallic Co-Ni two-dimensional polymer (2DP) model OER catalysts with well-defined architecture, monolayer characteristic, were designed and synthesized to explore the influence of the coupling strength between metal centers on OER performance. The coupling strength was regulated by adjusting the spacing between metal centers or the conjugation degree of bridge skeleton. Among the examined 2DPs, CoTAPP-Ni-MF-2DP, which has the strongest coupling strength between metal centers exhibited the best OER performance. These model systems can help to explore the precise structure-performance relationships, which is important for the rational catalyst design at the atomic/molecular levels.

6.
Angew Chem Int Ed Engl ; 61(46): e202207845, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36106432

RESUMO

Innovative bimetallic materials provide more possibilities for further improving the performance of oxygen evolution reaction (OER) electrocatalysts. However, it is still a great challenge to rationally design bimetallic catalysts because there is not a practical way to decouple the factors influencing the intrinsic activity of active sites from others, thus hindering in-depth understanding of the mechanism. Herein, we provide a rational design of bimetallic Ni, Co two-dimensional polymer model OER catalyst. The well-defined architecture, identical density of active sites and monolayer characteristic allow us to decouple the intrinsic activity of active sites from other factors. The results confirmed that the relative position and local coordination environment has significant effect on the synergistic effect of the bimetallic centres. The highest electrocatalytic activity with the turnover frequency value up to 26.19 s-1 was achieved at the overpotential of 500 mV.

7.
J Mater Chem B ; 10(20): 3793-3797, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35485398

RESUMO

Two-dimensional polymers functionalized with controllable density of carboxyl groups were constructed with the Langmuir-Blodgett method. Mineralization of calcium phosphate shows significantly different characteristics on these films, which clearly indicates that the density of carboxy groups plays a determining role in controlling the nucleation and orientated growth of calcium phosphate.


Assuntos
Fosfatos de Cálcio , Polímeros
8.
Anal Chem ; 94(17): 6615-6620, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35446018

RESUMO

The single molecule level determination with a transistor (SiMoT) platform has attracted considerable attention in the recognition of various ultralow abundance biomolecules, while complicated labeling and testing processes limit its further applications. Recently, organic field-effect transistor (OFET)-based biosensors are good candidates for constructing an advanced label-free SiMoT platform due to their facile fabrication process, rapid response time, and low sample volume with a wide range of detection. However, the sensitivity of most OFET-based biosensors is in the order of nM and pM, which cannot meet the detection requirements of ultralow abundance protein. Herein, a label-free SiMoT platform is demonstrated by integrating pillar[n]arene as a signal amplifier, and the detection limit can reach 4.75 aM. Besides, by simultaneous determination of α-fetoprotein, carcinoembryonic antigen, and prostate antigen, the proposed multiplexed OFET-based SiMoT platform provides a key step in reliable early cancer diagnosis.


Assuntos
Técnicas Biossensoriais , Neoplasias , Detecção Precoce de Câncer , Humanos , Nanotecnologia , Neoplasias/diagnóstico , Transistores Eletrônicos
9.
Nanoscale ; 13(29): 12466-12474, 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34477611

RESUMO

The development of optical materials with room temperature phosphorescence (RTP) and white light emission (WLEDs) is highly desirable and remains a challenging task. Herein, a porous metal-organic framework PCN-921 with a high quantum yield (ΦF = 93.6%) was achieved. To make full use of the advantages of the high porosity of PCN-921, we hierarchically encapsulated different guest molecules coronene and rhodamine B (RhB) into the framework. Unsurprisingly, the hybrid material coronene@PCN-921 was obtained after in situ encapsulation of the guest coronene into the framework, and it exhibits obvious RTP behavior with a long phosphorescence lifetime of 62.5 ns. Subsequently, second guest RhB molecules were introduced after soaking in RhB solution and the material RhB@coronene@PCN-921 was achieved. Interestingly, it exhibits white light emission with the CIE coordinates of (0.29, 0.34), and can be used as a high performance WLED lamp. This is the first work on dual-functional hybrid dyes@MOFs with hierarchical guest encapsulation for RTP and white light emission, which suggests the potential applications of MOFs in multifunctional optical devices.

10.
Chemistry ; 27(54): 13605-13612, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34312929

RESUMO

Nowadays, most manufacturing memory devices are based on materials with electrical bistability (i. e., "0" and "1") in response to an applied electric field. Memory devices with multilevel states are highly desired so as to produce high-density and efficient memory devices. Herein, we report the first multichannel strategy to realize a ternary-state memristor. We make use of the intrinsic sub-nanometer channel of pillar[5]arene and nanometer channel of a two-dimensional imine polymer to construct an active layer with multilevel channels for ternary memory devices. Low threshold voltage, long retention time, clearly distinguishable resistance states, high ON/OFF ratio (OFF/ON1/ON2=1 : 10 : 103 ), and high ternary yield (75 %) were obtained. In addition, the flexible memory device based on 2DPTPAZ+TAPB can maintain its stable ternary memory performance after being bent 500 times. The device also exhibits excellent thermal stability and can tolerate a temperature as high as 300 °C. It is envisioned that the results of this work will open up possibilities for multistate, flexible resistive memories with good thermal stability and low energy consumption, and broaden the application of pillar[n]arene.

11.
Chem Commun (Camb) ; 57(53): 6495-6498, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34100485

RESUMO

Herein, we illustrate how the cooperation of intermolecular hydrogen bonds and conformation flexibility leads to the formation of diverse complex covalent nanostructures on the surface, while the relative abundance of the final products can be further tuned by adjusting the molar ratio and concentration of monomers.

12.
Magn Reson Chem ; 59(8): 804-814, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33559222

RESUMO

A method for increasing the solubilities of industrial azo pigments in DMSO by adding DBU (1,8-diaza-7-bicyclo[5.4.0]undecene) has been developed. This facilitated the acquisition of solution 13 C NMR spectra of the pigments. This method was applied to four types of azo pigments: naphthol AS (3-hydroxy-2-naphthoic acid anilide) pigments, naphthol pigments, pyrazolone pigments and acetoacetanilide pigments. This represents the first solution 13 C NMR spectra for naphthol AS pigments. Altogether 18 industrial azo pigments were analysed using 1D and 2D NMR techniques. The proton and corresponding carbon NMR resonances of these pigments have all been assigned.


Assuntos
Compostos Azo/química , Corantes/química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Dimetil Sulfóxido/química , Espectroscopia de Prótons por Ressonância Magnética/métodos , Solubilidade
13.
Chem Commun (Camb) ; 57(16): 2065-2068, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33507169

RESUMO

Herein, we designed and synthesized a precursor with a three-fold node and successfully constructed covalent Sierpinski triangle (ST) fractals with boronic ester linkages both at the liquid/solid interface at room temperature and by thermal annealing in a water atmosphere under ambient conditions. Remarkably, large-scale ordered superstructures of covalent STs are constructed by thermal annealing, which paves the way for property investigation of STs.

14.
Chem Commun (Camb) ; 56(81): 12182-12185, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-32914798

RESUMO

By the co-assembly of two carboxylic acids with distinct symmetries and different numbers of carboxyl groups, we obtained two novel cocrystal structures at the n-octanoic acid/HOPG interface, one of which was sustained by unoptimized R22(8) hydrogen bonding. Benefiting from the bias-sensitivity of the BTB (1,3,5-tris(4-carboxyphenyl)benzene) molecule, a structure transition between the cocrystal network and a denser BTB lamella is achieved.

15.
ACS Omega ; 3(8): 9027-9033, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31459035

RESUMO

Multistep reactions are often required for the transformation of alcohols to α-chloroacetals via the unstable intermediates aldehydes or α-halo aldehydes. Herein, we report a simplified procedure for practical synthesis of α-chloroacetals using 2,2,6,6-tetramethylpiperidine-1-oxyl as a catalyst and trichloroisocyanuric acid both as an oxidant and a chlorination reagent. The reaction is one-pot, solvent-free and high-yielding. In addition, the α-chloroacetals have been transformed to enol ethers through the elimination reaction in the presence of sodium.

16.
Zhongguo Zhong Yao Za Zhi ; 40(7): 1370-5, 2015 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-26281563

RESUMO

Rats were continuously given different doses of water extract of Polygonum multiflorum (1, 10 g x kg(-1)) for 7 days to prepare liver microsomes. Cocktail in vitro incubation approach and Real-time quantitative PCR technology were used to observe the effect of water extract of P. multiflorum on CYP450 enzymatic activities and mRNA expressions in rat liver. Compared with the blank control group, both 1, 10 g x kg(-1) water extract of P. multiflorum treated groups showed significant inhibitions in CYP2E1 enzymatic activities and mRNA expressions (enzymatic activities of CYP2E1, P < 0.01; mRNA expression of CYP2E1, P < 0.05 in 1 g x kg(-1) group, P < 0.01 in 10 g x kg(-1) group). They revealed a significant increase in the enzymatic activity of CYP3A1 (P < 0.01), but without significant change in mRNA expressions. The 10 g x kg(-1) group showed a significant inhibition in CYP1A2 enzymatic activities and mRNA expressions in rat livers (P < 0.01).


Assuntos
Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP2E1/genética , Inibidores das Enzimas do Citocromo P-450/administração & dosagem , Medicamentos de Ervas Chinesas/administração & dosagem , Fígado/efeitos dos fármacos , Fígado/enzimologia , Polygonum/química , Animais , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2E1/metabolismo , Inibidores das Enzimas do Citocromo P-450/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
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