Serum amyloid A (SAA) is a key biomarker for diagnosing inflammatory responses in diseases like influenza and COVID-19. An electrochemiluminescence (ECL) biosensor has been constructed for signal enhancement in SAA detection by encapsulating 4,4',4″,4‴-(1,3,6,8-pyrenetetrayl) tetrakis-benzoic acid (TBAPy) into liposomes. Such biomimetic encapsulation shields the biologically important membrane to avoid aggregation of TBAPy and prevents quenching.
View Article and Find Full Text PDFThe concentration of zinc ions in semen is significantly correlated with sperm viability and male fertility. In this work, a reliable ratiometric fluorescence probe (ZIF-9-TCPP) based on the efficient Förster resonance energy transfer (FRET) process between two luminophores, benzimidazole (BIM) and -tetra (4-carboxyphenyl) porphyrin (TCPP) for Zn detection has been constructed, where the emissions of BIM and TCPP are used as reference and detection signals. The proximity of BIM and TCPP in one framework (ZIF-9-TCPP) and the overlapped spectra between BIM and TCPP afford the attainment of a highly efficient FRET (around 90% efficiency).
View Article and Find Full Text PDFEfficient and robust electrochemiluminescence (ECL) emitters are crucial for enhancing the ECL immunosensor sensitivity. This study introduces a novel ECL emitter, CoBIM/Cys, featuring a hierarchical core-shell structure. The core of the structure is created through the swift coordination between the sulfhydryl and carboxyl groups of l-cysteine (l-Cys) and cobalt ions (Co), while the shell is constructed by sequentially coordinating benzimidazole (BIM) with Co.
View Article and Find Full Text PDFPrecise tuning the structure of catalytic center is of great importance for the construction of enhanced electrochemiluminescence (ECL) emitters and the development of ECL amplification strategies, which is a key factor in improving the sensitivity of biosensors. In this work, we report the enhanced ECL emitters based on the porphyrin-based paddlewheel framework (PPF) with axial coordinated imidazole-like ligands (PPF/X, X = 2-methylimidazole (MeIm), imidazole (Im), benzimidazole (BIM)). In this system, the electron-donating ability of the axial ligands is positively correlated to its coordination ability to the paddlewheel units and the catalytic ability of the axially coordinated paddlewheel units.
View Article and Find Full Text PDFSelective and sensitive detection of nitrite has important medical and biological implications. In the present work, to obtain an enhanced electrochemiluminescence (ECL) determination of nitrite, a novel nano-ECL emitter CoBIM/cetyltrimethylammonium bromide (CTAB) was prepared via a micelle-assisted, energy-saving, and ecofriendly method based on benzimidazole (BIM) and CTAB. Unlike conventional micelle assistance, the deprotonated BIM (BIM) preferential placement was in the palisade layer of cationic CTAB-based micelles.
View Article and Find Full Text PDFBiomass carbon dots (CDs) derived from natural plants possess the advantages of low cost, photostability, and excellent biocompatibility, with potential applications in chemical sensing, bioimaging, and nanomedicine. However, the development of biomass CDs with excellent antioxidant activity and good biocompatibility is still a challenge. Herein, we propose a hypothesis for enhancing the antioxidant capacity of biomass CDs based on precursor optimization, extraction solvent, and other conditions with broccoli as the biomass.
View Article and Find Full Text PDFConstructing robust and efficient luminophores is of significant importance in the development of electrochemiluminescence (ECL) amplification strategies. Inspired by the resonance energy transfer in natural light-harvesting systems, we propose a novel ECL amplification system based on ECL resonance energy transfer (ECL-RET), which integrates two luminophores, benzimidazole (BIM) and zinc(II) tetrakis(4-carboxyphenyl)porphine (ZnTCPP), into one framework. Through disassembling and reconstruction processes, numerous BIM surround ZnTCPP in the constructed ZIF-9-ZnTCPP.
View Article and Find Full Text PDFACS Appl Mater Interfaces
February 2023
Exploring the depolymerization strategy of liposoluble luminophores in the aqueous phase is vital for the development of electrochemiluminescence (ECL). In this work, tetraoctylammonium bromide (TOAB) with four long hydrophobic chains and short hydrophilic ends is used as a template to limit the aggregation of benzimidazole (BIM). By adjusting the loading of BIM on the hydrophobic chains of TOAB, a two-dimensional lamellar BIM/TOAB is formed, the ECL intensity of which is 6.
View Article and Find Full Text PDFDue to the complexity of the synthetic process of cobalt phosphides (CoP), ongoing efforts concentrate on simplifying the preparation process of CoP. In this work, amino tris(methylene phosphonic acid) (ATMP, L1) and melamine (MA, L2) are assembled into two-dimensional (2D) organic nanostructures by hydrogen bonding and ionic interactions a supramolecular assembly, which greatly weakens the coordination ability of L1 with Co. As the introduced L2 is rich in carbon and nitrogen, it allows the cobalt-organophosphate complex to be placed under a strongly reducing atmosphere during the high-temperature calcination process to achieve an phosphating purpose.
View Article and Find Full Text PDFIn the rapid development of artificial nanomaterials comparable to biological enzymes, we propose herein a novel concept for the construction of functional materials inspired from chemical evolution. To mimic the formation process of the catalytic system for the origin of life, dicyandiamide (DCD) was used as an elemental molecule for the synthesis of an electrocatalyst. DCD was initially condensed with glucose (Glu) to form carbon dots (CDs) a hydrothermal method.
View Article and Find Full Text PDFHigh electrocatalytic activity with tunable luminescence is crucial for the development of electrochemiluminescence (ECL) luminophores. In this study, a porphyrin-based heterobimetallic 2D metal organic framework (MOF), [(ZnTCPP)Co(MeIm)] (1), is successfully self-assembled from the zinc(II) tetrakis(4-carboxyphenyl)porphine (ZnTCPP) linker and cobalt(II) ions in the presence of 2-methylimidazole (MeIm) by a facile one-pot reaction in methanol at room temperature. On the basis of the experimental results and the theoretical calculations, the MOF 1 contains paddle-wheel [Co(-CO)] secondary building units (SBUs) axially coordinated by a MeIm ligand, which is very beneficial to the electron transfer between the Co(II) ions and oxygen.
View Article and Find Full Text PDFA novel electrochemiluminescence (ECL) amplification strategy was established aiming to overcome the inherent shortcomings of the current oxygen (O) coreactant ECL systems. Macrocyclic Schiff base Fe complexes were rationally designed as a novel integrated ECL emitter by iminium linkage between -(4-aminobutyl)--ethylisoluminol (ABEI) and 1,10-phenanthroline-2,9-dicarbaldehyde (PDL) and postmetalation of the macrocyclic Schiff base. Covalently combining luminophore ABEI with a catalytic center endowed the novel ECL emitter with both remarkable redox electrocatalytic properties and significantly enhanced ECL efficiency.
View Article and Find Full Text PDFIn view of the shortcomings of the current coreactant electrochemiluminescence (ECL) and inspired by natural oxygen (O) reduction metalloenzymes, a novel ECL amplification strategy was established. A pyrolytic iron- and nitrogen-doped (Fe-N-C) nanosheet rich in singly ionized oxygen vacancy (V) defects was rationally designed by destroying the highly saturated coordination with a preorganized ligand 1,10-phenanthroline-2,9-dicarboxylic acid (PDA). Extraordinary catalytic activity for O activation was obtained via screening a special pyrolysis temperature using spectroscopic and electrochemical methods.
View Article and Find Full Text PDFReasonable control of the redox states within the catalytic units together with the interconnection degrees of the substrate is of great significance in the modulation of a well-performing transducer. Herein, a novel carbon black (CB)-modified copper metal-organic framework nanomaterial (CB@Cu-MOF) prepared at room temperature was utilized as a precursor to synthesize mixed-valent copper-oxide composite catalysts (NC/CuO-). By tuning the carbonization process of the precursor at different temperatures ( = 100 °C, 200 °C, 300 °C and 400 °C), the different ratio configurations of the redox-alternated CuO portions were successfully controlled with the simultaneous effective tailoring of the defect abundance in the N-doped carbon substrate.
View Article and Find Full Text PDFMetal-organic frameworks (MOFs) act as versatile coordinators for the subsequent synthesis of high-performance catalysts by providing dispersed metal-ion distribution, initial coordination condition, dopant atom ratios, and so on. In this work, a crystalline MOF -[Cu(NO)(Him)] was synthesized as the novel precursor of a redox-alternating CuO electrochemical catalyst. Through simple temperature modulation, the gradual transformation toward a highly active nanocomposite was characterized to ascertain the signal enhancing mechanism in HO reduction.
View Article and Find Full Text PDFEnzyme mimetics have attracted wide interest due to their inherent enzyme-like activity and unique physicochemical properties, as well as promising applications in disease diagnosis, treatment and monitoring. Inspired by the attributes of nonheme iron enzymes, synthetic models were designed to mimic their capability and investigate the catalytic mechanisms. Herein, metal-organic gels (Fe-MOGs) with horseradish peroxidase (HRP) like Fe-N structure were successfully synthesized though the coordination between iron and 1,10-phenanthroline-2,9-dicarboxylic acid (PDA) and exhibited excellent peroxidase-like activity.
View Article and Find Full Text PDFPrecise control over the composition, morphology, and size of porphyrin-based metal-organic frameworks is challenging, but the extension of these hybrid materials will enable the creation of novel electrochemiluminescence (ECL) emitters. The coordination of various entities is made from Zn ions and meso-tetra(4-carboxyphenyl)porphine (TCPP), modulated by both solvent and bathophenanthrolinedisulfonic acid disodium salt (BPS) as capping agent, resulting in limited crystal growth of Zn-TCPP in DMF/HO (v/v, 1:1) and the formation of nanoscale TCPP-Zn-BPS. The role of BPS is also evaluated using Zn-TCPP and BPS-Zn-TCPP as controls, prepared in the absence of BPS and different coordinating sequences of ligands, respectively.
View Article and Find Full Text PDFReliable and sensitive detection of xanthine has important medical and biological significance. In this work, a novel three-dimensional (3D) conductive polymer hydrogel of polyaniline (PAni) was feasibly prepared using aniline (Ani), amino trimethylene phosphonic acid (ATMP) and ammonium persulfate ((NH)SO) as monomer, gelatinizing agent and oxidizing agent, respectively. Protonation of aniline can be achieved by ATMP, inducing good conductivity of the obtained hydrogel.
View Article and Find Full Text PDFACS Appl Mater Interfaces
September 2019
Glycopolymers have emerged as powerful and versatile glycan analogues for the investigation of cellular signal transduction. In this study, a layer of the glycopolymer-brush (GlyB) interface was functionalized on the surface of gold substrates. In order to enhance the capability and accessibility of this transducer interface, a combined protocol of copper(0)-mediated living radical polymerization (Cu(0)-LRP) with subsequent "CuAAC" click reaction was utilized to synthesize a set of novel glycopolymer precursors with a tunable scaffold structure and pyranose ligands.
View Article and Find Full Text PDFACS Appl Mater Interfaces
June 2017
In this work, we synthesized the one-dimensional nanostructure of zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP) via a self-assembly technique. Using sodium dodecyl sulfate (SDS) as "soft template", the self-assembled ZnTPyP (SA-ZnTPyP) had the morphology of hexagonal nanoprisms with a uniform size (diameter of 100 nm). The SA-ZnTPyP exhibited remarkably different spectral properties compared to those of the original ZnTPyP.
View Article and Find Full Text PDFIn this work, a new visual colorimetric strip based on cellulose acetate nanofiber mats modified by 2-(5-Bromo-2-pyridylazo)-5-(diethylamino) phenol was successfully prepared via electrospinning technology. The prepared colorimetric strip showed high sensitivity towards UO with the yellow-to-purple color change signal. Upon the optimal conditions of solution pH at 6.
View Article and Find Full Text PDFA simple and rapid photoelectrochemical (PEC) sensor was developed for the label-free detection of a phosphoprotein (α-casein) based on a zirconium based porphyrinic metal-organic framework (MOF), PCN-222, which exhibited an enhanced photocurrent response toward dopamine under the O-saturated aqueous media. In this work, in terms of PEC measurements and cyclic voltammetry, the PEC behaviors of PCN-222 in aqueous media were thoroughly investigated for the first time. Additionally, in the virtue of the steric hindrance effect from the coordination of the phosphate groups and inorganic Zr-O clusters as binding sites in PCN-222, this biosensor showed high sensitivity for detecting α-casein and the limit of detection (LOD) was estimated to be 0.
View Article and Find Full Text PDFIt is still a huge challenge to find a new strategy for rationally designing covalent drugs because most of them are discovered by serendipity. Considering that the effect of covalent drugs is closely associated with the kinetics of the reaction between drug molecule and its target protein, here we first demonstrate an example of the kinetic effect of pi-stacking of drug molecules on covalent antimicrobial drug design. When PEGylated 7-aminocephalosporanic acid (PEG-ACA) is used as a substrate drug, pi-stacking of the ACA group via the self-assembly of PEG-ACA on the surface of gold nanoparticles (i.
View Article and Find Full Text PDFA Zr-based metal-organic framework with zinc tetrakis(carboxyphenyl)-porphyrin (ZnTCPP) groups (MOF-525-Zn) was utilized to develop a novel electrochemiluminescence (ECL) biosensor for highly sensitive protein kinase activity assay. In this work, in terms of ECL measurements and cyclic voltammetry, the cathodic ECL behaviors of MOF-525-Zn in aqueous media were thoroughly investigated for the first time. The photoelectric active groups ZnTCPP on the MOF-525-Zn frameworks could promote the generation of singlet oxygen ((1)O2) via a series of electrochemical and chemical reactions, resulting in a strong and stable red irradiation at 634 nm.
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