Fiber-Optic Photoacoustic Gas Sensor with Multiplexed Fabry-Pérot Interferometric Cantilevers.

A fiber-optic photoacoustic (PA) gas sensor with multiplexed Fabry-Pérot (F-P) interferometric cantilevers is demonstrated. A compact cylindrical nonresonant PA tube with a volume of only 0.45 mL is designed.

Dynamic detection of ppb-level SO based on a differential photoacoustic cell coupled with UV-LED.

We design a photoacoustic (PA) SO sensor based on the coupling of a differential photoacoustic cell (DPAC) and cost-effective UV-LED, which realized the dynamic monitoring of SO gas at the ppb level. Aiming at the limitation of UV-LED divergence, a light source combination module with high condensing efficiency was devised based on a lens through theoretical derivation and experimental analysis. The PA signal with the optimum matching of the lens was 20-times larger than the direct coupling of the UV-LED.

Multi-pass Differential Photoacoustic Sensor for Real-Time Measurement of SF Decomposition Component HS at the ppb Level.

We designed and implemented a photoacoustic (PA) sensor for HS detection in SF background gas based on a multi-pass differential photoacoustic cell (MDPC) and a near-infrared distributed feedback (DFB) laser. In the MDPC apparatus, two resonators with identical geometric parameters were vertically and symmetrically embedded. The differential processing algorithm of two phase-reversed signals realized the effective enhancement of the PA signal and suppressed the flow noise in the dynamic sampling process.

Self-enhancement photoelectrochemical strategy for kanamycin determination with amino functionalized MOFs.

Based on the self-enhanced photoelectrochemical quality of Cu-MOF-NH, a photoelectrochemical biosensor for kanamycin detection with a Cu-MOF-NH modified electrode was constructed. This biosensor took full advantage of the low electron hole recombination rate due to the ligand-to-metal charge-transfer mechanism of excited electron transfer in Cu-MOF-NH. The kanamycin aptamer was modified onto Cu-MOF-NH by Schiff base reaction.

Chemiluminescence assay for kanamycin based on target recycling strategy.

A chemiluminescence (CL) sensing strategy for kanamycin residue detection in fish samples was established based on luminol-functionalized gold nanoparticles as CL nanoprobe materials combined with DNA hairpin structure and carboxyl-modified magnetic beads. Relying on nucleic acid amplification technology, the system can successfully realize the recycling of kanamycin, so that the biosensor can release a large number of luminol-functionalized gold nanoparticles with excellent CL performance even at a low residual levels of kanamycin. The biosensor strategy showed a good linear relationship with kanamycin in the range 0.

Photoelectrochemical aptasensor with low background noise.

In photoelectrochemical (PEC) detection, enhancing the PEC signal and depressing the blank signal are conducive to improve the sensitivity. Because the carbon nanotube (CNT) effectively transfers photogenerated electrons from SnSe to the electrode, the composite nanomaterial CNTs/SnSe generates a strong PEC signal. Methionine (Met), AuNPs, and probe DNA are woven together forming a nanoprobe which is used as a quencher to quench the PEC signal of CNTs/SnSe.

NiFe-coordinated zeolitic imidazolate framework derived trifunctional electrocatalyst for overall water-splitting and zinc-air batteries.

Developing high-efficient non-noble metal electrocatalysts toward oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), water-splitting, and the zinc-air battery is essential but challenging. Zeolitic imidazole frameworks (ZIFs) are generally employed as ideal platforms for the design and fabrication of energy-related catalysts by exploiting their porous structure with high surface area and flexibility. This work presents the preparation of NiFe-bimetallic species decorated N-doped porous carbon composite (NiFe@NPC) through pyrolyzing the NiFe-coordinated ZIF precursor.

3D hierarchical porous nitrogen-doped carbon/Ni@NiO nanocomposites self-templated by cross-linked polyacrylamide gel for high performance supercapacitor electrode.

Three-dimensional nitrogen-doped carbon network incorporated with nickel@nickel oxide core-shell nanoparticles composite (3D NC/Ni@NiO) has been facilely prepared, self-templated by the cross-linked polyacrylamide aerogel precursor containing NiCl. Characterizations reveal that the Ni@NiO nanoparticles distribute homogeneously in the 3D nitrogen-doped carbon matrix and the composite is of hierarchical porous structure. When used as supercapacitor electrode in a three-electrode system, the 3D NC/Ni@NiO exhibits enhanced electrical conductivity and excellent electrochemical performance, presenting a high specific capacitance (389F g at 5 mV s), good rate capability (276 F g at 100 mV s) and outstanding cycling performance (with the capacitance retention of 70.

A cascade autocatalytic strand displacement amplification and hybridization chain reaction event for label-free and ultrasensitive electrochemical nucleic acid biosensing.

Herein, an autocatalytic strand displacement amplification (ASDA) strategy was proposed for the first time, which was further ingeniously coupled with hybridization chain reaction (HCR) event for the isothermal, label-free and multiple amplification toward nucleic acid detection. During the ASDA module, the target recognition opens the immobilized hairpin probe (IP) and initiates the annealing of the auxiliary DNA strand (AS) with the opened IP for the successive polymerization and nicking reaction in the presence of DNA polymerase and nicking endonuclease. This induces the target recycling and generation of a large amount of intermediate DNA sequences, which can be used as target analogy to execute the autocatalytic strand displacement amplification.

Photoelectrochemical platform for cancer cell glutathione detection based on polyaniline and nanoMoS composites modified gold electrode.

Herein, a visible light photoelectrochemical (PEC) platform based on polyaniline (PANI) and nanoMoS composites as optoelectronic material for glutathione detection without any auxiliary of biomolecules or labeled materials was developed. Firstly, the nanoMoS was prepared via a simple ultrasound exfoliation method. The PANI was synthesized by chemical oxidative polymerization method.

A hierarchical Co-Fe LDH rope-like nanostructure: facile preparation from hexagonal lyotropic liquid crystals and intrinsic oxidase-like catalytic activity.

Hierarchical rope-like structures based on Co-Fe layered double hydroxide (LDH) nanosheets were synthesized by the coprecipitation method from a hexagonal lyotropic liquid crystal (LLC) nanoreactor, and were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric (TG) and inductively coupled plasma (ICP) analyses. It was found that the rope-like LDH structures were composed of LDH nanosheets with a lateral size of about 200-400 nm and an average thickness of 4.47 nm in the form of face-to-edge interactions.

Surfactant-free microemulsion composed of oleic acid, n-propanol, and H2O.

Generally, a microemulsion consists of oil, water, surfactant, and sometimes cosurfactant. Herein, we report a surfactant-free microemulsion (denoted as SFME), consisting of oleic acid (oil phase), water, and n-propanol without the amphiphilic molecular structure of a traditional surfactant. The phase behavior of the ternary system was investigated, showing that there were a single-phase microemulsion region and a multiphase region in the ternary phase diagram.