scanning-electron-microscopy-energy-dispersive-spectroscopy

Scanning Electron Microscopy-Energy Dispersive Spectroscopy Evaluation of a Retinal Explant Model of Iron Intraocular Foreign Body Injury

Iron intraocular foreign body (IOFB) can cause retinal damage, which may be related to the release, transfer, and tissue infiltration of iron particles. ...

Shantou University

HKUST-1 MOFs and its derivative HKUST-CuO were coupled with TiO nanoparticles to form the heterogeneous composites of HKUST-1/TiO and HKUST-CuO/TiO based on their well-suitable bandgap energies (Eg). Compared with mono-component HKUST-1 or HKUST-CuO, the prepared composites displayed photoelectrochemical (PEC) response due to the synergistic effect from their heterogeneous structure. Higher photocurrent response was obtained on HKUST-CuO/TiO-modified ITO electrode (HKUST-CuO/TiO/ITO), which could be attributed to the hollow structure with a thin shell of HKUST-CuO greatly enhancing visible spectra harvesting. The CuO component in HKUST-CuO not only could accelerate electron transfer on the heterojunction interface but also effectively separate the photo-generated charge carriers (e/h). Based on the excellent PEC performance of prepared photoactive composite material, under visible-light excitation (λ ≥ 420 nm) and with a working potential of 0 V (vs. Ag/AgCl), the S1 (probe DNA)/HKUST-CuO/TiO/ITO PEC platform was successfully fabricated for colitoxin DNA detection without using ascorbic acid (AA) as an electron donor. Compared with the analysis results on S1/HKUST-1/TiO/ITO electrode, S1/HKUST-CuO/TiO/ITO displayed a wider linear response range from 1.0 × 10 to 4.0 × 10 nM with a lower detection limit of 3.73 × 10 nM (S/N = 3), the linear regression equation was ΔI (10 A) =0.5549-0.1858 log (C/M), which confirmed the HKUST-CuO could improve sensitivity because of its prominent PEC property. The relative standard deviation (RSD) of the PEC sensor for target DNA detection of 2.0 × 10 nM was 7.4%. The proposed DNA biosensor also possessed good specificity and stability. Hence, this reported work was a promising strategy for molecular diagnosis in the bio-analysis field. (A) Schematic illustration of the preparation process of the proposed PEC biosensors for colitoxin DNA detection. (B) The preparation process of HKUST-1 and HKUST-CuO.

An enhanced photoelectrochemical biosensor for colitoxin DNA based on HKUST-1/TiO and derived HKUST-CuO/TiO heterogeneous composites.

Heterostructured construction is regarded as a valuable approach to improve photoelectrochemical (PEC) performances. Herein, porous hollow NiS@NiO spheres were prepared derived from the Ni(TCY) MOFs precursor. Photoactive TiO was coupled with as-prepared NiS@NiO to form a close heterojunction interface of NiS@NiO/TiO. NiS@NiO/TiO modified ITO electrode (NiS@NiO/TiO/ITO) displayed fiercely enhanced photocurrent response, which was 4687-fold than that of NiS@NiO/ITO (0.008 μA) and 8.5-fold than that of TiO/ITO (4.41 μA), respectively. Remarkable PEC property could be ascribed to the hollow NiS@NiO spheres with thin-shell structure provided there is a larger active surface area for harvesting the visible light. Most importantly, the p-n type NiS@NiO/TiO heterojunction could lead to generating more photo-excited charge carriers (e/h) and efficiently hinder the recombination of carriers, resulting in significantly augmented photocurrent output. Based on this outstanding PEC property, NiS@NiO/TiO/ITO electrode fabricated sensing platform (BSA/anti-CEA/NiS@NiO/TiO/ITO, BSA=Bovine serum albumin) exhibited high sensitivity for monitoring CEA (Carcinoembryonic antigen). Wide linear detection range was from 0.001 to 45 ng mL and with a low detection limit of 1.67 × 10 ng mL (S/N = 3). Prepared biosensors also showed good reproducibility, stability and had satisfying specificity. Thus, the proposed NiS@NiO/TiO heterostructured composite afforded well-design and synthesis strategy for constructing high-performance photoactive materials from MOFs-derivate.

A highly sensitive photoelectrochemical biosensor for CEA analysis based on hollow NiS@NiO/TiO composite with typal p-n heterostructure.

High-throughput biofluid metabolomics analysis for screening life-threatening diseases is urgently needed. However, the high salt content of biofluid samples, which introduces severe interference, can greatly limit the analysis throughput. Here, a new 3-D interconnected hierarchical superstructure, namely a "plasmonic gold-on-silica (Au/SiO) double-layered aerogel", integrating distinctive features of an upper plasmonic gold aerogel with a lower inert silica aerogel was successfully developed to achieve  separation and storage of inorganic salts in the silica aerogel, parallel enrichment of metabolites on the surface of the functionalized gold aerogel, and direct desorption/ionization of enriched metabolites by the photo-excited gold aerogel for rapid, sensitive, and comprehensive metabolomics analysis of human serum/urine samples. By integrating all these unique advantages into the hierarchical aerogel, multifunctional properties were introduced in the SALDI substrate to enable its effective utilization in clinical metabolomics for the discovery of reliable metabolic biomarkers to achieve unambiguous differentiation of early and advanced-stage lung cancer patients from healthy individuals. This study provides insight into the design and application of superstructured nanomaterials for  separation, storage, and photoexcitation of multi-components in complex biofluid samples for sensitive analysis.

Hierarchical superstructure aerogels for  biofluid metabolomics.

Benzo[a]pyrene (B[a]P), a ubiquitous environmental pollutant, poses a significant threat to male reproductive health, but the underlying latent molecular mechanisms remain virtually unknown. This study investigated the effects of embryonic B[a]P exposure on testicular function and spermatogenesis in F0 and F1 adult male medaka (). Embryos were exposed to sublethal concentrations (2.5, 20, and 80 μg/L) for 8 days and then raised in clean water until they reached adulthood. Transcriptomic analysis of F0 testicular tissues revealed widespread dysregulation of critical pathways. Exposure impaired the brain-pituitary-gonadal axis by disrupting GnRH signaling and downregulating genes encoding key steroidogenic enzymes (, ), indicating suppressed testosterone biosynthesis. Concurrently, pathways essential for cellular energy metabolism (AMPK signaling, insulin signaling), amino acid biosynthesis, and cytoskeletal organization (actin cytoskeleton, focal adhesion) were profoundly altered. Furthermore, B[a]P activated apoptotic pathways and disrupted the balance between cell survival (PI3K-Akt signaling) and death, compromising spermatogenic cell fate. These molecular disruptions manifested in drastic physiological impairments, including a reduced gonadosomatic index, decreased sperm motility, and compromised fertilization success in F0 males, although these effects were recovered in the F1 generation. This study provides a comprehensive molecular basis for the long-term reproductive toxicity of early-life B[a]P exposure.

Article	Year
An enhanced photoelectrochemical biosensor for colitoxin DNA based on HKUST-1/TiO and derived HKUST-CuO/TiO heterogeneous composites. Mikrochimica acta\| PubMed ID: 34495380	2021
A highly sensitive photoelectrochemical biosensor for CEA analysis based on hollow NiS@NiO/TiO composite with typal p-n heterostructure. Talanta\| PubMed ID: 35550510	2022
Hierarchical superstructure aerogels for biofluid metabolomics. Nanoscale\| PubMed ID: 38602354	2024
Embryonic Benzo[a]pyrene Exposure Induces Multigenerational Reproductive Effects on Adult Male Medaka: Phenotypic and Transcriptomic Insights. Toxics\| PubMed ID: 41150585	2025

Jiayang Chen

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