Substrate-Switched Dual-Signal Self-Powered Sensing System Based on Dual-Nanozyme Activity of Bimetal-Doped CeO Nanospheres for Electrochemical Assay of Aflatoxin B1.

The long-term operation feature of enzymatic biofuel cell-based self-powered biosensor (EBFC-SPB) endows them with the potential to execute dual-signal biosensing without having to integrate an extra signal acquisition device. Herein, cobalt and manganese codoped CeO nanospheres (CoMn-CeO NSs) with glucose-oxidase-like and peroxidase-like activities have been developed as substrate-switched dual-channel signal transduction components in EBFC-SPB for a dual-signal assay of aflatoxin B1 (AFB1). The CoMn-CeO NSs modified with aptamer are anchored to a complementary DNA-attached bioanode of EBFC-SPB by base complementary pairing, which catalyze the glucose oxidation together with the glucose oxidase (GOx) on the bioanode.

Recent advances in microbial fuel cell-based self-powered biosensors: a comprehensive exploration of sensing strategies in both anode and cathode modes.

With the rapid development of society, it is of paramount importance to expeditiously assess environmental pollution and provide early warning of toxicity risks. Microbial fuel cell-based self-powered biosensors (MFC-SPBs) have emerged as a pivotal technology, obviating the necessity for external power sources and aligning with the prevailing trends toward miniaturization and simplification in biosensor development. In this case, vigorous advancements in MFC-SPBs have been acquired in past years, irrespective of whether the target identification event transpires at the anode or cathode.

Carbon dots as light-responsive oxidase-like nanozyme for colorimetric detection of total antioxidant capacity in fruits.

Evaluation of total antioxidant capacity (TAC) in fruits is essential for dietary guidance and health monitoring. Here, we have exploited light-response carbon dots (CDs) as oxidase-like nanozyme to determine the TAC of fruits. The CDs possess excellent oxidase-like activity with light stimulation due to the accelerated intramolecular charge transfer caused by abundant electron donating/drawing groups in precursors.

Damage-Free and Time-Saving Platform Integrated by a Flow Membrane Separation Device and a Dual-Target Biofuel Cell-Based Biosensor for Continuous Sorting and Detection of Exosomes and Host Cells in Human Serum.

The growth relationship between exosomes (EXOs) and the host cells is highly desired for tumor evaluations, which puts forward high demand on the accurate and convenient acquisition of their individual quantitative information. However, the tedious and destructive separation process and the requirement of dual-channel detection make it become an extremely challenging task. Herein, we integrated an enzymatic biofuel cell (EBFC)-powered biosensor with a flow cell-supported membrane separation device (FMSC) to develop a continuous separation and detection platform for EXOs and host cancer cells in human serum.

Label-Free Probing of Electron Transfer Kinetics of Single Microbial Cells on a Single-Layer Graphene via Structural Color Microscopy.

Studies of electron transfer at the population level veil the nature of the cell itself; however, in situ probing of the electron transfer dynamics of individual cells is still challenging. Here we propose label-free structural color microscopy for this aim. We demonstrate that MR-1 cells show unique structural color scattering, changing with the redox state of cytochrome complexes in the outer membrane.

Layer-by-layer assembly of Au and CdS nanoparticles on the surface of bacterial cells for photo-assisted bioanodes in microbial fuel cells.

Surface modification of exoelectrogens with photoelectric materials is a promising way for achieving photo-assisted microbial fuel cells (MFCs). However, the poor conductivity of most photoelectric materials inevitably hampers the electron transfer inside bacterial biofilms. Herein, by utilizing the electrostatic layer-by-layer assembly strategy, the conductive Au nanoparticles (NPs) and photo-responsive CdS NPs were alternatively modified onto the surface of Escherichia coli for photo-assisted bioanodes in MFCs.

Electrode Materials Engineering in Electrocatalytic CO Reduction: Energy Input and Conversion Efficiency.

Electrocatalytic CO reduction (ECR) is a promising technology to simultaneously alleviate CO -caused climate hazards and ever-increasing energy demands, as it can utilize CO in the atmosphere to provide the required feedstocks for industrial production and daily life. In recent years, substantial progress in ECR systems has been achieved by the exploitation of various novel electrode materials. The anodic materials and cathodic catalysts that have, respectively, led to high-efficiency energy input and effective heterogenous catalytic conversion in ECR systems are comprehensively reviewed.

Plasmon Coupling-Enhanced Raman Sensing Platform Integrated with Exonuclease-Assisted Target Recycling Amplification for Ultrasensitive and Selective Detection of microRNA-21.

A "signal-off" surface-enhanced Raman scattering (SERS) platform has been constructed for ultrasensitive detection of miRNA-21 by integrating exonuclease-assisted target recycling amplification with a plasmon coupling enhancement effect. On this platform, Raman-labeled Au nanostar (AuNS) probes can be covalently linked with the thiolated aptamer (Apt) on the Au-decorated silicon nanowire arrays (SiNWAs/Au) substrate, creating a coupled electromagnetic field between the substrate and the probes to enhance Raman signal. In the presence of miRNA-21, T7 exonuclease specifically hydrolyzed Apt on Apt/miRNA duplex to release miRNA-21.

A glucose/O fuel cell-based self-powered biosensor for probing a drug delivery model with self-diagnosis and self-evaluation.

Extending the application of self-powered biosensors (SPB) into the drug delivery field is highly desirable. Herein, a robust glucose/O fuel cell-based biosensor is successfully integrated with a targeted drug delivery system to create a self-sustained and highly compact drug delivery model with self-diagnosis and self-evaluation (DDM-SDSE). The glucose/O fuel cell-based biosensor firstly performs its diagnostic function by detecting the biomarkers of cancer.

Plasmonic Au nanostar Raman probes coupling with highly ordered TiO/Au nanotube arrays as the reliable SERS sensing platform for chronic myeloid leukemia drug evaluation.

The accurate therapeutic evaluation for chronic myeloid leukemia (CML) drug is of great importance to minimize side effects and enhance efficacy. Herein, a facile and precise surface-enhanced scattering (SERS) approach based on coupled plasmonic field has been introduced to evaluate the therapeutic outcomes of antileukemia drug through ultrasensitive assay of caspase-3 activity in apoptotic cells. Caspase-3 as an apoptosis indicator could specifically cleave the N-terminus of biotinylated DEVD-peptide (biotin-Gly-Asp-Gly-Asp-Glu-Val-Asp-Gly-Cys) immobilized on the Au nanoparticle-decorated TiO nanotube arrays (TiO/Au NTAs) substrate.

Oxygen Species on Nitrogen-Doped Carbon Nanosheets as Efficient Active Sites for Multiple Electrocatalysis.

Designing and synthesizing nanomaterials with high coverages of active sites is one of the most-pivotal factors in the construction of state-of-the-art electrocatalysts with high performance. Herein, we proposed a facile in situ templated method for the fabrication of oxygen-species-modified nitrogen-doped carbon nanosheets (O-N-CNs). The epoxy oxygen and ketene oxygen combined with graphitic-nitrogen defects in O-N-CNs gave more active sites for the oxygen-reduction reaction (ORR) and the oxygen-evolution reaction (OER), as proven via theoretical and experimental results, while the carbonyl-oxygen and epoxy-oxygen species showed more efficient electrocatalytic activity for the hydrogen evolution reaction (HER).

Correction: Visible-light-enhanced power generation in microbial fuel cells coupling with 3D nitrogen-doped graphene.

Correction for 'Visible-light-enhanced power generation in microbial fuel cells coupling with 3D nitrogen-doped graphene' by Dan Guo et al., Chem. Commun.

Visible-light-enhanced power generation in microbial fuel cells coupling with 3D nitrogen-doped graphene.

A new visible-light-assisted microbial fuel cell composed of a three-dimensional nitrogen-doped graphene self-standing sponge anode and a photoresponsive cathode has been developed for achieving multiple energy conversion and a higher power output.

Living and Conducting: Coating Individual Bacterial Cells with In Situ Formed Polypyrrole.

Coating individual bacterial cells with conjugated polymers to endow them with more functionalities is highly desirable. Here, we developed an in situ polymerization method to coat polypyrrole on the surface of individual Shewanella oneidensis MR-1, Escherichia coli, Ochrobacterium anthropic or Streptococcus thermophilus. All of these as-coated cells from different bacterial species displayed enhanced conductivities without affecting viability, suggesting the generality of our coating method.

Graphene/Fe O Nanocomposites as Efficient Anodes to Boost the Lifetime and Current Output of Microbial Fuel Cells.

The enhancement of microbial activity and electrocatalysis through the design of new anode materials is essential to develop microbial fuel cells (MFCs) with longer lifetimes and higher output. In this research, a novel anode material, graphene/Fe O (G/Fe O ) composite, has been designed for Shewanella-inoculated MFCs. Because the Shewanella species could bind to Fe O with high affinity and their growth could be supported by Fe O , the bacterial cells attached quickly onto the anode surface and their long-term activity improved.

Bacteria-Affinity 3D Macroporous Graphene/MWCNTs/Fe3O4 Foams for High-Performance Microbial Fuel Cells.

Promoting the performance of microbial fuel cells (MFCs) relies heavily on the structure design and composition tailoring of electrode materials. In this work, three-dimensional (3D) macroporous graphene foams incorporated with intercalated spacer of multiwalled carbon nanotubes (MWCNTs) and bacterial anchor of Fe3O4 nanospheres (named as G/MWCNTs/Fe3O4 foams) were first synthesized and used as anodes for Shewanella-inoculated microbial fuel cells (MFCs). Thanks to the macroporous structure of 3D graphene foams, the expanded electrode surface by MWCNTs spacing, as well as the high affinity of Fe3O4 nanospheres toward Shewanella oneidensis MR-1, the anode exhibited high bacterial loading capability.