Citrate is essential to biomineralization of the bone especially as an integral part of apatite nanocomposite. Citrate precipitate of apatite is hypothesized to be derived from mesenchymal stem/stromal cells (MSCs) upon differentiation into mature osteoblasts. Based on 13C‐labeled signals identified by solid‐state multinuclear magnetic resonance analysis, boosted mitochondrial activity and carbon‐source replenishment of tricarboxylic acid cycle intermediates coordinate to feed forward mitochondrial anabolism and deposition of citrate. Moreover, zinc (Zn2+) is identified playing dual functions: (i) Zn2+ influx is influenced by ZIP1 which is regulated by Runx2 and Osterix to form a zinc‐Runx2/Osterix‐ZIP1 regulation axis promoting osteogenic differentiation; (ii) Zn2+ enhances citrate accumulation and deposition in bone apatite. Furthermore, age‐related bone loss is associated with Zn2+ and citrate homeostasis; whereas, restoration of Zn2+ uptake alleviates age‐associated declining osteogenic capacity and amount of citrate deposition. Together, these results indicate that citrate is not only a key metabolic intermediate meeting the emerging energy demand of differentiating MSCs but also participates in extracellular matrix mineralization, providing mechanistic insight into Zn2+ homeostasis and bone formation.

Rational construction of strong electron-transfer materials remains a challenging task. Herein, we show a fundamental design rule for construction of strong electron-transfer materials through covalently integrating electron-donoring Cu(I) clusters and electron-withdrawing triazine monomers together. As expected, the two resultant Cu(I)-triazine frameworks (Cu-CTFs) showed strong electron transfer up to 0.46|e| from each Cu(I) metal center to each adjacent triazine fragment, and the size of triazine monomer was found to give tunable ability for electron transfer. Accompanied to the stronger electron transfer is the observation of more narrow bang gap and good spatial separation of HOMO and LUMO level. This finally leads to good spatial separation of photo-generated electron-hole pairs and function units for boosting photocatalytic reduction of uranium under ambience and no sacrificial agent with ultrahigh removal efficiency up to 99.7%, and good charge separation of [I+][I5-] for boosting I2 immobilization under extremely rigorous conditions with benchmark I2 uptake of 0.32 g/g. The results not only have opened up a structural design principle to access electron-transfer materials, but also solved several challenging tasks in the field of radionuclide capture and CTFs.