As a powerful tool for chemical biology, bioorthogonal chemistry broadens the ways to explore the mystery of life. In this field, transition metal catalysts (TMCs) have received much attention because TMCs can rapidly catalyze chemical transformations that cannot be accomplished by bio-enzymes. However, fine controlling chemical reactions in living systems like bio-enzymes is still a great challenge. Herein, we construct a versatile light-controlled bioorthogonal catalyst by modifying macroporous silica-Pd0 with supramolecular complex of azobenzene (Azo) and β-cyclodextrin (CD). Its catalytic activity can be regulated by light-induced structural changes, mimicking allosteric regulation mechanism of bio-enzymes. The light-gated heterogeneous TMCs are important for in situ controlling bioorthogonal reactions and have been successfully used to synthesize a fluorescent probe for cell imaging and mitochondria-specific targeting agent by Suzuki–Miyaura cross-coupling reaction. Endowing the bioorthogonal catalyst with new functions is highly valuable for realizing more complex researches in biochemistry.

As at ypical bioorthogonal reaction, the coppercatalyzedazide-alkyne cycloaddition (CuAAC) has been used for drug design and synthesis.H owever,f or localized drug synthesis,i ti si mportant to be able to determine where the CuAACr eaction occurs in living cells.I nt his study,w e constructed ah eterogeneous copper catalyst on am etalorganic framework that could preferentially accumulate in the mitochondria of living cells.Our system enabled the localized synthesis of drugs through as ite-specific CuAACr eaction in mitochondria with good biocompatibility.I mportantly,t he subcellular catalytic process for localized drug synthesis avoided the problems of the delivery and distribution of toxic molecules.I nv ivo tumor therapye xperiments indicated that the localized synthesis of resveratrol-derived drugs led to greater antitumor efficacy and minimized side effects usually associated with drug delivery and distribution.

Presented are the development of novel 0D-2D nanohybrids consist of nickel-based bimetal phosphorus trisulfides (Ni 1−x Fe x PS 3 ) nanomosaic that decorated on the surface of MXene nanosheets (denoted as NFPS@MXene). The nanohybrids are obtained through a facile self-assemble process of transition metal layered double hydroxide (TMLDH) on MXene surface; followed by the low temperature in-situ solid-state reaction step. By tuning the Ni:Fe ratio, the as-synthesized NFPS@MXene nanohybrids exhibit excellent activities when tested as electrocatalysts for overall water splitting. Particularly, with the initial Ni:Fe ratio of 7:3, the obtained Ni 0.7 Fe 0.3 PS 3 @MXene nanohybrid reveals low overpotential (282 mV) and Tafel slope (36.5 mV dec -1 ) for oxygen evolution reaction (OER) in 1 m KOH solution. Meanwhile, the Ni 0.9 Fe 0.1 PS 3 @MXene shows low overpotential (196 mV) for hydrogen evolution reaction (HER) in 1 m KOH solution. When integrated them for overall water splitting, the Ni 0.7 Fe 0.3 PS 3 @MXene || Ni 0.9 Fe 0.1 PS 3 @MXene couple shows a low onset potential of 1.42 V and needs only 1.65 V to reach a current density of 10 mA cm -2 , which is better than the all noble metal IrO 2 || Pt/C electrocatalyst (1.71 mV@10 mA cm −2 ). Given the chemical versatility of Ni 1−x Fe x PS 3 and the convenient self-assemble process, the nanohybrids demonstrated in this work are promising for energy conversion applications.