Embracing Nature's Wisdom: Liposome-Mediated Amplification of Electrochemiluminescence for the Sensitive and Selective Immunoassay of Serum Amyloid A.

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.

A novel light-harvesting ZIF-9-TCPP as a promising FRET-based ratiometric fluorescence probe for sperm mobility.

The 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).

l-Cysteine-Tuned the Hierarchical Structure Based on Benzimidazole: Synthesis, Characterization, and Application in Ratiometric Electrochemiluminescence Immunoassay.

Efficient 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.

A Conductive Microcavity Created by Assembly of Carbon Nanotube Buckypapers for Developing Electrochemically Wired Enzyme Cascades.

We describe the creation of a conductive microcavity based on the assembly of two pieces of carbon nanotube buckypaper for the entrapment of two enzymes, horseradish peroxidase (HRP) and glucose oxidase (GOx), as well as a redox mediator: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid diammonium salt (ABTS). The hollow electrode, employing GOx, HRP, and the mediator, as an electrochemical enzyme cascade model, is utilized for glucose sensing at a potential of 50 mV vs. Ag/AgCl.

Fine tuning of porphyrin based-paddlewheel framework by imidazole derivative to boost electrochemiluminescence performance.

Precise 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.

Micelle-Assisted Confined Coordination Spaces for Benzimidazole: Enhanced Electrochemiluminescence for Nitrite Determination.

Selective 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.

Chlorhexidine digluconate exerts bactericidal activity vs Gram positive Staphylococci with bioelectrocatalytic compatibility: High level disinfection for implantable biofuel cells.

Implanted devices destined for contact with sterile body tissues, vasculature or fluids should be free of any microbial contamination that could lead to disease transmission. The disinfection and sterilisation of implantable biofuel cells is a challenging and largely overlooked subject due to the incompatibility of fragile biocatalytic components with classical treatments. Here we report the development of a convenient "soft" chemical treatment based on immersion of enzymatic bioelectrodes and biofuel cells in dilute aqueous chlorhexidine digluconate (CHx).

Artificial Light-Harvesting System Based on Zinc Porphyrin and Benzimidazole: Construction, Resonance Energy Transfer, and Amplification Strategy for Electrochemiluminescence.

Constructing 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.

Tuning Dimensionality of Benzimidazole Aggregates by Using Tetraoctylammonium Bromide: Enhanced Electrochemiluminescence Studies.

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.

Nanostructured electrodes based on multiwalled carbon nanotube/glyconanoparticles for the specific immobilization of bilirubin oxidase: Application to the electrocatalytic O reduction.

Here we describe the design and the characterization of novel electrode materials consisting of multi-walled carbon nanotubes coated with glyconanoparticles (GNPs) functionalized with anthraquinone sulfonate. The resulting modified electrodes were characterized by scanning electron microscopy and cyclic voltammetry. Their electrochemical behavior reveals a stable pH-dependent redox signal characteristic of anthraquinone sulfonate.

Regulating the coordination capacity of ATMP using melamine: facile synthesis of cobalt phosphides as bifunctional electrocatalysts for the ORR and HER.

Due 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.

Cu(II)-assisted self-assembly of dicyandiamide-derived carbon dots: construction inspired from chemical evolution and its HO sensing application.

In 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.

2D Zn-Porphyrin-Based Co(II)-MOF with 2-Methylimidazole Sitting Axially on the Paddle-Wheel Units: An Efficient Electrochemiluminescence Bioassay for SARS-CoV-2.

High 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.

Schiff Base Complexes with Covalently Anchored Luminophores: Self-Enhanced Electrochemiluminescence Detection of Neomycin.

A 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.

Hollow Bioelectrodes Based on Buckypaper Assembly. Application to the Electroenzymatic Reduction of O.

A new concept of hollow electrode based on the assembly of two buckypapers creating a microcavity which contains a biocatalyst is described. To illustrate this innovative concept, hollow bioelectrodes containing 0.16-4 mg bilirubin oxidase in a microcavity were fabricated and applied to electroenzymatic reduction of O in aqueous solution.

Trialkoxyheptazine-Based Glyconanoparticles for Fluorescence in Aqueous Solutions and on Surfaces via Controlled Binding in Space.

The fluorescent organic 2,5,8-tris((adamantan-1-yl)-methoxy)-heptazine (HTZ-Ad) was solubilized in water by inclusion of adamantane groups into free β-cyclodextrins or a cyclodextrin shell of glyconanoparticles. These glyconanoparticles with average diameters between 40 and 60 nm result from the self-assembly of polystyrene--β-cyclodextrin copolymers. Under UV irradiation at 365 nm, the modified nanoparticles exhibit fluorescence emission in aqueous media as well as in their adsorbed state.

A membraneless starch/O biofuel cell based on bacterial surface regulable displayed sequential enzymes of glucoamylase and glucose dehydrogenase.

Enzymatic biofuel cells (EBFCs) provide a new strategy to enable direct biomass-to-electricity conversion, posing considerable demand on sequential enzymes. However, artificial blend of multi-enzyme systems often suffer biocatalytic inefficiency due to the rambling mixture of catalytic units. In an attempt to construct a high-performance starch/O EBFC, herein we prepared a starch-oxidizing bioanode based on displaying a sequential enzyme system of glucoamylase (GA) and glucose dehydrogenase (GDH) on E.

Organic β-cyclodextrin Nanoparticle: An Efficient Building Block Between Functionalized Poly(pyrrole) Electrodes and Enzymes.

Glyconanoparticles (GNPs) made by self-assembly of carbohydrate-based polystyrene-block-β-cyclodextrin copolymer are used as a building block for the design of nanostructured biomaterials of electrode. The firm immobilization of GNPs is carried out on electrochemically generated polymer, poly(pyrrole-adamantane), and copolymer, poly(pyrrole-adamantane)/poly(pyrrole-lactobionamide) via host-guest interactions between adamantane and β-cyclodextrin. The ability of GNPs for the specific anchoring of biological macromolecules is investigated using glucose oxidase enzyme modified by adamantane groups as a protein model (GOx-Ad).

Rational Design of a Highly Dispersed Fe-N-C Nanosheet with 1,10-Phenanthroline-2,9-Dicarboxylic Acid as a Preorganized Ligand: Boosted Electrochemiluminescence Detection of Tetracycline.

In 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.

Multi-tailoring of a modified MOF-derived CuO electrochemical transducer for enhanced hydrogen peroxide sensing.

Reasonable 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.

Postmodulation of the Metal-Organic Framework Precursor toward the Vacancy-Rich CuO Transducer for Sensitivity Boost: Synthesis, Catalysis, and HO Sensing.

Metal-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.