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Photoelectrochemical (PEC) bioanalysis represents a unique and dynamically developing methodology that offers an elegant route for sensitive biomolecular detection. Aptamers are synthetic nucleic acid molecules whose binding characteristics can rival those of protein antibodies. Originated from the fusion of PEC bioanalysis and aptamers, PEC aptasensing has rapidly becoming a subject of new research interests in recent years. Using illustrative examples, this review provides the introductory concept, bioanalysis development, signaling strategies, and the state of the art in this field. The future prospects are also discussed. [ABSTRACT FROM AUTHOR]

This work reports the development of affinity systems with dual octapeptide ligands for affinity adsorption and purification of human IgG (hIgG) and monoclonal antibody (mAb). The three octapeptide ligands, FYWHCLDE (1), FYCHWALE (2), and FYCHTIDE (3), identified earlier by the biomimetic design strategy were used; any two of the three were mixed and coupled to Sepharose gel, leading to the formation of three dual-ligand affinity systems. Research emphasis was first placed on hIgG adsorption isotherms and the results were compared to the three single-ligand affinity systems. It was found that there was synergistic effect of the two peptide ligands in a dual-ligand system, so the affinity of a dual-ligand resin for hIgG was higher than those of its counterparts, single-ligand resins. Of the three dual-ligand systems, the FYWHCLDE (1)–FYCHTIDE (3) resin showed the highest affinity, so it was selected for investigating the effects of ligand density and molar ratio on hIgG adsorption equilibrium. It was found that the synergistic effect increased with increasing the total ligand density of the two peptides in the dual-ligand affinity system. Moreover, the FYWHCLDE (1)–FYCHTIDE (3) system at a molar ratio of 2:1 displayed the highest affinity for hIgG (0.69 μM at a total ligand density of 31.1 μmol/mL), indicating that the synergistic effect reached the maximum at this ratio. This dual-ligand affinity column was then used for the purification of hIgG and mAb by affinity chromatography, resulting in over 95% pure hIgG and mAb at recovery yield over 90%. Molecular docking of the two peptides to the Fc fragment simultaneously showed that FYWHCLDE (1) stood still but FYCHTIDE (3) shifted aside the CH2 CH3 inter-domain. Molecular dynamics simulation of the binding process of the two octapeptides to Fc revealed that both the peptide ligands kept stable interactions with Fc. The synergistic effect of the dual-ligand affinity system was thus elucidated by the molecular simulations. [ABSTRACT FROM AUTHOR]

• In this work, we use the slave-boson mean field theory to study the Yu-Shiba-Rusinov resonance states in monolayer FeSe superconductor grown on SrTiO3 substrate. In the strong correlation regime and at zero temperature, the slave-boson mean field method can capture the qualitative physics of the resonance states induced by quantum magnetic impurity. • We find that both the spin-orbital coupling and interband pairing can induce a splitting of the resonance peaks for d -wave pairing. This result has not been proposed in previous studies on this superconductor. • We find different signatures of magnetic impurity resonance states for different pairing symmetries, our results can help to identify the pairing symmetry of this superconductor;these researches will be useful for future studies of the pairing mechanism. In this work, we study the magnetic impurity resonance states in monolayer FeSe superconductor for different pairing symmetries. When the magnetic impurity is hybridized to one of the two electronic pockets at M point, we find that there will be two in-gap resonance peaks located symmetrically at the two sides of the Fermi energy. The intensities of the two peaks are comparable for s -wave and d -wave pairings. For the p -wave pairing, the intensity of the positive resonance peak is much smaller than the negative one. When the magnetic impurity is hybridized to the two electronic pockets simultaneously and spin-orbit coupling is considered, the two resonance peaks will be split into four for d -wave pairing. This splitting is absent for s -wave and p -wave pairings. These features can be considered as signatures to distinguish the pairing potential symmetries. [ABSTRACT FROM AUTHOR]

The removal and biomineralization of Pb2+ (200 mg/L) in water were investigated utilizing mature mycelia of Phanerochaete chrysoporium. Mycelial dosage, initial Pb2+ concentration, solution pH and treatment time all were shown to have an influence on Pb2+ removal. Granular, lead-containing precipitation was formed on the fungal hyphae upon exposure to lead nitrate, which was confirmed from scanning electron micrograph/Energy Dispersive Spectrometer (SEM/EDS). Energy dispersive X-ray spectroscopic analysis revealed the presence of lead (48.5% by weight) along with phosphorus in the precipitate. This extracellular precipitate was further identified as pyromorphite lead hydroxyphosphate [Pb 5 (PO 4) 3 OH] by X-ray powder diffraction (XRD) analysis. During Pb2+ removal, size-enlarged mineral precipitation, and clustered nanospherical particles formed on the hyphae were revealed by SEM/XRD. A remarkable increase of mycelial phosphatase activity of 1.5 times that of the control and decreased phosphate concentration in solution (16.76 mg/L to 1.39 mg/L) initially upon exposure to Pb2+ suggested that phosphatase may hydrolyze organic phosphorus into inorganic phosphate and release it into solution, participating in the biomineralization of Pb2+. Toxicity tests showed that the toxicity of Pb2+ polluted water decreased after treatment. The results clearly demonstrate previously unknown lead biomineralization as pyromorphite through fungal phosphatase. Image 1055115 • Lead pollution poses a potential threat to human health and the environment. • The removal and biomineralization of Pb2+in water was performed by fungus P. chrysoporium. • XRD analysis demonstrated that Pb2+ was mineralized into Pb 5 (PO 4) 3 OH. • The process involves the hydroxylation of organic phosphorus by phosphatase. • The Pb2+ mineralization to Pb 5 (PO 4) 3 OH by a fungus has been shown firstly. [ABSTRACT FROM AUTHOR]

A polysaccharide CP1-1 was isolated and purified from Celosia cristata . Its average molecular weight was 2.3 kDa and it was composed of glucose and galactose in a ratio of 1.00:2.03, and traces of mannose. Chemical characterization of CP1-1 was elucidated by methylation analysis. CP1-1 was a branched glucogalactan which was mainly composed of 1,6-linked Gal p and 1,6-linked Glc p with a ratio of 5.6:3.8. The branches were at the O -3 of the main chain and might be composed of single terminal (1→)-linked glucopyranose and galactopyranose. CP1-1 also significantly promoted the proliferation and neutral red phagocytosis of RAW 264.7 macrophage cells in vitro . In addition, CP1-1 promoted cell proliferation by enhancing the production of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1β. These results suggested that the polysaccharide from C. cristata could be used as a potential immunostimulator. [ABSTRACT FROM AUTHOR]

Abstract: A sensitive photoelectrochemical (PEC) approach for Pb2+ sensing was achieved firstly with the coupling of G-quadruplex-based DNAzyme and biocatalytic precipitation (BCP) on a CdS quantum dots electrode. Pb2+ can induce the conformational change of K+-stabilized G-quadruplex-based DNAzyme, leading to the decrease of the catalytic activity to H2O2-mediated 4-chloro-1-naphthol oxidation (BCP reaction). From the respective BCP reaction that monitors the event of DNAzyme deactivation, a novel PEC Pb2+ sensor could be realized with a detection limit of 1.0×10−8 M. [Copyright &y& Elsevier]

For strip surface defect detection, the key is to achieve reliable detection results with high detection speed. This paper mainly focuses on the ability to distinguish defects with similar optical characteristics, and the balance between detection accuracy and speed. Firstly, the dataset with 2020 pictures containing 6 types of defects was established by the figures inspected in a rolled titanium strip production line. Then, a novel detection model named Yolo-SAGC was proposed by applying two strategies to the fast response Yolo-v5 model. One is to improve the feature recognition capability by combining self-attention and graphic convolution in the head module. The other is to make a thorough slim of the whole network architecture by using slim modules combined with depth-wise separable convolution (i.e., DWconv). Finally, the advancement of this novel detection model was verified by the self-established database. The results demonstrate a significant reduction in cases where detection is missed for the 6 types of defects, dropping from 32.75% to 6.67% when the two strategies are implemented. Notably, the most difficult-to-detect label "Pit" defect shows an 11.9% improvement in average precision with the introduction of self-attentional graphic convolution. Similarly, the densely distributed small target "Little_lightspot" exhibits a 5.0% increase in average precision when DWconv is applied. Furthermore, the mAP @0.5 of Yolo-SAGC is comparable to that of Yolo-v8, while the model parameters are decreased by 48.7% and FPS is increased by 3. These phenomena show the great potential of Yolo-SAGC in industrial applications. [ABSTRACT FROM AUTHOR]

Herein, we describe a customized approach for facile preparation of three-dimensional (3D) NiO nanoflakes (NFs)/carbon fiber meshwork (CFM) and its validation as a common photocathode matrix for photoelectrochemical (PEC) bioanalysis, which to our knowledge has not been reported. Specifically, 3D NiO NFs/CFM was fabricated by a sequential liquid phase deposition and annealing process, which was then characterized by scanning electron microscopy, X–ray photoelectron spectrum, UV–vis absorption spectra and N 2 adsorption-desorption measurement. Sensitized by BiOI and incorporated with an alkaline phosphatase (ALP)/tyrosinase (TYR) bi-enzyme cascade system, a sensitive split-type cathodic PEC bioanalysis for the determination of ALP was achieved. This method can detect ALP concentrations down to 3 × 10−5 U L−1 with a linear response range of 0.001–10 U L−1. Moreover, this proposed system exhibited good selectivity, stability and excellent performance for real sample analysis. This research features the facile preparation of 3D NiO NFs/CFM that could acts as a universal matrix for photocathodic analysis, and is envisioned to stimulate more effort for advanced 3D photocathode for PEC bioanalysis and beyond. Facile preparation of 3D NiO NFs/CFM as a common photocathode matrix for the split-type cathodic PEC probing of ALP activity. Image 1 • 3D NiO nanoflakes/carbon fiber meshwork was fabricated. • Sensitive cathodic PEC enzymatic bioanalysis was thus achieved. • This elegant sensing of ALP demonstrated high sensitivity, selectivity and stability. • It could be used as general cathodic photoelectrochemical bioanalysis platform. [ABSTRACT FROM AUTHOR]

Liposome-assisted photoelectrochemical (PEC) bioanalysis represents one of the latest frontiers in the arena of PEC bioanalysis. This work reports a general enzyme-amplified liposomal PEC bioanalysis protocol via the use of enzyme-loaded liposomes to boost the biocatalytic precipitation (BCP) effect. In the representative system, the horseradish peroxidase (HRP)-loaded liposome (HRPLL) and the Au nanoclusters (NCs)/Au nanoparticles (NPs)/TiO 2 nanotubes (NTs) framework (AATF) were used as liposomal label and photoelectrode, respectively. In the detection, the sandwich immunocomplex reaction was accomplished in a 96-well plate to confine the HRPLL label, which was then lysed to release the HRP molecules to initiate the BCP process. Due to the amplified formation of HRP-induced BCP on the AATF scaffold, the photo-current response correlated closely with the immunorecognition process and the analyte could be detected very sensitively. This work features the first integration of enzyme-loaded liposomes and the BCP for sensitive PEC bioanalysis, which to our knowledge has not been reported. With the use of various other enzymes, this work could serve as a general basis for the PEC bioanalysis of numerous other target of interest. Image 1 • Peroxidase (HRP)-loaded liposomes were prepared. • The released HRP could induce enhanced biocatalytic precipitation. • The as-derived photoelectrochemical immunoassay has good performance. [ABSTRACT FROM AUTHOR]