Jianbo Wang

Efficient delivery of mRNA to the bone marrow is crucial for maintaining immune homeostasis and understanding the pathogenesis of numerous disorders. However, achieving effective delivery remains challenging due to the low blood perfusion of bone tissue and the restrictive blood-bone marrow barrier. Conventional strategies for developing and screening bone-targeting carriers mainly rely on in vitro bone-binding assays and lack robust in situ evaluation tools. Here, we report a BODIPY-doped nanocarrier engineering (BONE) strategy that leverages NIR-II bioimaging for guided development and screening of mRNA delivery systems targeting the bone marrow. A library of NIR-II-emissive BODIPY dyes with intrinsic bone marrow tropism was doped onto lipid nanoparticles (LNPs) to construct BONE LNPs. Using NIR-II imaging, we achieve in situ, noninvasive, and real-time visualization of the bone-targeting capability of these LNPs prior to performing in vivo mRNA transfection studies. Among the formulations, BONE-2 LNPs demonstrate the highest bone accumulation at 24 h postinjection. Flow cytometry of bone marrow cells further reveal that BONE-2 LNPs preferentially localize to myeloid populations─including monocytes, macrophages, and dendritic cells─resulting in a 3.3-fold improvement in bone marrow mRNA transfection compared with a commercial LNP formulation. Together, this work establishes that integrating NIR-II BODIPY dyes into LNPs provides not only an effective strategy for targeted mRNA delivery to the bone marrow but also a generalizable framework for NIR-II imaging-guided screening of nanocarriers tailored to specific tissues.

Synthesis process for the Al-Py monomer, preparation of Py-FMIP and the procedure for oxytetracycline (OTC) detection using Py-FMIP.

Cysteine (Cys) is a crucial biothiol that acts a significant function in food samples and biological systems, including plant roots and living cells. Hence, we developed a novel colorimetric and near-infrared ratiometric fluorescent probe (CT), composed of coumarin and tetrahydroacridine-conjugated indole salt, for the detection of Cys. Upon reaction with Cys, the probe undergoes a specific N-substitution reaction, resulting in a notable colorimetric change and a significant ratiometric fluorescent response in both visible and near-infrared emission channels. These dual-channel ratiometric fluorescence changes are completely independent, enabling the probe to obtain great selectivity, sensitivity, and exceptional detection accuracy. Leveraging these attributes, the probe was employed to provide accurate quantitative analysis of Cys in food samples. Furthermore, confocal imaging demonstrated that the probe could monitor both exogenous and endogenous Cys levels in living cells and track Cys changes in plant roots under heavy metal stress. This work presents a dependable and accurate imaging solution for tracking and identifying Cys of real food, plants, and living cells.