A responsive hydrogen-bonded cholesteric liquid crystal polymer (CLCP) film with controlled porosity was fabricated as an optical sensor to distinguish between methanol and ethanol in alcohol solutions. To facilitate responding the alcohols, porosity was generated by removing the nonreactive liquid crystal agent, and the hydrogen bridges of CLCP were broken. The sensitivities of CLCPs to ethanol and methanol were obtained by monitoring the wavelength shifts of the transmission spectrum at different alcohol concentrations and ratios of methanol/ethanol. Changes in the central wavelength of the CLCP network transmission spectrum allowed the methanol–ethanol ratio to be discriminated. A linear relationship between wavelength shift of CLCP networks and alcohol concentration was obtained experimentally, and the sensor characteristics were explored. The sensitivities of the CLCPs were 1.35 and 0.18 nm/% to ethanol and methanol, respectively. The sensing sensitivity of cholesteric networks to alcohol molecules increased as the methanol–ethanol ratio declined. Therefore, CLCP could act as a stimuli-responsive material to distinguish the concentrations of acetone and ethanol in mixed solutions. Furthermore, the impact of UV intensity for curing a CLC mixture on the sensing sensitivity to the different alcohol concentrations was also studied. The higher UV intensity could enhance the sensitivity to alcohol molecules and distinguishing ability between methanol and ethanol.

Accurate detection of target analytes and generation of highfidelity fluorescence signals are particularly critical in life sciences and clinical diagnostics. However, the majority of current NIR-I fluorescent probes are vulnerable to pH effects resulting in signal distortion. In this work, a series of fluorescence-tunable and pH-independent probes are reported by combining optically tunable groups of unsymmetric Si-rhodamines and introducing the methoxy instead of the spiro ring on the benzene ring at position 9. To validate the concept, the leucine aminopeptidase response site was introduced into Si-2,6OMe-NH 2 with the best optical properties to synthesize Si-LAP for monitoring the intrahepatic LAP in vivo. Therefore, the design approach may provide a new and practical strategy for designing innovative functional fluorescent probes and generating high-stability and high-fidelity fluorescent signals.

Herein, a Zr‐based dual‐ligand MOFs with pre‐installed Rh complex was employed for NADH regeneration in situ and also used for immobilization of formic acid dehydrogenase (FDH) in order to realize a highly efficient CO2 fixation system. Then, based on the detailed investigations into the photochemical and electrochemical properties, it is demonstrated that the introduction of the photosensitive meso‐tetra(4‐carboxyphenyl) porphin (TCPP) ligands increased the catalytic active sites and improved photoelectric properties. Furthermore, the electron mediator Rh complex, anchored on the zirconium‐based dual‐ligand MOFs, enhanced the efficiency of electron transfer efficiency and facilitated the separation of photogenerated electrons and holes. Compared with UiO‐66‐NH2, Rh‐H2TCPP‐UiO‐66‐NH2 exhibits an optimized valence band structure and significantly improved photocatalytic activity for NAD+ reduction, resulting the synthesis of formic acid from CO2 increased from 150 μg mL−1 (UiO‐66‐NH2) to 254 μg mL−1 (Rh‐H2TCPP‐UiO‐66‐NH2). Moreover, the assembled photocatalyst‐enzyme coupled system also allows facile recycling of expensive electron mediator, enzyme, and photocatalyst.

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An enzyme–photocatalyst hybrid system has been developed for aldehyde-based indole C-3 acylation. The concept of this process is to form a C–N bond through the three-component Mannich reaction of aldehydes, amines, and indoles, thereby introducing an aminomethyl group on the indole ring. Next, this system catalyzed the formation of the corresponding imide ion from the Mannich product, followed by rapid hydrolysis to give the final C-3 carbonyl indole product. More than 30 indole C-3 acylated products (up to 93% yield) were successfully synthesized under mild conditions, and indole derivatization of two bioactive substances (probenecid and cholesterol) was realized. The mechanistic study provides theoretical support for the construction of photoenzyme catalytic systems. This is an example of enzyme–light-activated C-3 acylation of indoles under very mild reaction conditions, without the use of transition metal catalysts, metal salts, and additional oxidants. This efficient enzyme–photocatalyst hybrid system provides a strategy for the development of photoenzyme catalysis fields.