Guangxi Normal University

Serum amyloid A (SAA) is a more sensitive indicator for the early detection of infections compared to traditional biomarkers like C-reactive protein. This study aimed to construct a highly sensitive electrochemiluminescence (ECL) immunosensor employing lanthanide bimetallic-organic framework (Eu/Tb-MOF) in conjunction with CoSn(OH)₆-Au nanocomposites for precise quantification of SAA. The sensor was constructed using an Eu/Tb-MOF, where Eu³⁺ and Tb³⁺ functioned as the central metal ions and 1,3,5-tris(4-carboxyphenyl)benzene (H₃BTB) served as the organic ligand. H₃BTB transmits its energy to Eu³⁺ and Tb³⁺ through the antenna effect and europium(III) is used as an electrocatalyst, leading to significant amplification of their characteristic ECL emissions. CoSn(OH)₆-bound gold nanoparticles provide binding sites for the antibodies, with simultaneous improvement in the interfacial electron transfer rate of CoSn(OH)₆. Under optimal conditions, the engineered immunosensor platform exhibited a linear range from 10 fg‧mL^-1 to 100 ng‧mL^-1 and achieved a detection limit as low as 2.6 fg‧mL^-1. Method validation revealed quantitative recoveries (98.20-102.5 %) and exceptional reproducibility (relative standard deviation ≤ 1.7 %), validating the excellent operational stability and target-specific recognition capability of the assay in complex serum matrices. Therefore, the proposed immunosensor can be successfully applied for detecting SAA in biological specimens and also provides a promising approach for detecting other biomarkers.

Near-infrared II (NIR-II) photoacoustic (PA) imaging offers enhanced performance through reduced photon scattering, minimized background interference, and improved resolution at greater depths, thereby driving urgent demand for NIR-II PA nanoprobes in translational biomedicine. In this study, we developed a smart stannous sulfide@cuprous oxide (SnS@Cu₂O) nanoprobe for colorectal cancer PA imaging within NIR-II window. Under the existence of HS^-, the SnS@Cu₂O nanoprobe exhibits a broad absorption peak within the 1000-1300 nm range, enabling concentration-dependent NIR-II PA signal amplification in colorectal cancer tissues with overexpression of endogenous H₂S. The in vitro PA intensity was linearly correlated to HS^- concentration in the range of 0-1.2 mM. Intratumoral injection of SnS@Cu₂O nanoprobe (10 mg/kg) induced time-dependent PA signal amplification at the tumor site, exhibited rapid intensification, peaking at 4-h post-administration. Additionally, the SnS@Cu₂O can catalyze the Cu⁺ with H₂O₂ in the tumor tissue yielding ·OH via Fenton-like reactions for photothermal-enhanced chemodynamic therapy, enabling NIR-II PA imaging-guided therapy against deep-tissue colorectal tumor. This paper reports on the synthesis and application of a smart SnS@Cu₂O nanoprobe that was activated by colorectal tumor microenvironment.

Auxin/Indole-3-Acetic Acids(Aux/IAAs), a class of early auxin-responsive genes, encode short-lived nuclear proteins that play pivotal roles in auxin signaling. In vascular plants, Aux/IAA genes form large families-such as the 29 members in Arabidopsis, exhibiting both functional redundancy and specificity. Canonical Aux/IAA proteins contain four conserved domains and mediate nuclear auxin response by interacting with Transport Inhibitor Response 1/Auxin Signaling F-box (TIR1/AFB) auxin receptors and Auxin Response Factor (ARF) transcription factors. Loss- and gain-of-function mutants have been instrumental in dissecting the roles of individual Aux/IAAs. Recent studies have also uncovered the mechanism of non-canonical Aux/IAAs, which lack one or more conserved domains and regulate auxin signaling through distinct pathways. This review summarizes the structural features of Aux/IAA proteins, the functional diversity of non-canonical members, the phenotypic effects of their mutants, and their expression patterns. These findings reveal a hierarchical regulatory network of the Aux/IAA gene family in auxin signaling - balancing robustness through functional redundancy and precision and flexibility through member-specific functions in plant growth and development.