中国科学院化学所王树团队报了光催化CO₂还原共轭聚合物的合理设计——朝向局部CO产生和巨噬细胞极化。相关研究成果发表在2024年8月15日出版的《美国化学会杂志》。

光在疾病治疗中具有巨大的潜力，开发高效的光催化剂可以提高光催化系统在生物医学中的利用率。

该文中，研究人员设计了一种新的方法来设计和合成共轭聚合物的光催化剂，用于光催化二氧化碳还原，该方法依赖于用理论计算的描述符建立的多元线性回归模型。研究人员建立了分子结构与CO产率之间的对数关系，并确定聚芴-共聚噻吩偏差（PFT）为最佳偏差。PFT在乙腈中激发了231 nmol h^-1的CO再生率，在水溶液中激发了46 nmol h^-l的CO再生率，反应选择性为88%。通过开发包封PFT用于靶向巨噬细胞递送的脂质体，取得了进一步的进展。

通过在脂质体膜上分布PFT，构建的光催化系统有效地从周围的CO₂中原位产生CO。这种局部CO产生充当内源性信号分子，促进巨噬细胞从M1表型到M2表型的理想极化。因此，M2细胞减少了促炎细胞因子（TNF-α、IL-6和IL-1β）的分泌。研究还证明了该系统在白光照射下治疗脂多糖诱导的心肌细胞炎症的有效性。此外，研究通过理论计算和实验技术的结合，包括瞬态吸收、飞秒超快光谱和原位红外光谱，全面了解了二氧化碳减排中涉及的复杂过程。

研究结果为共轭聚合物和光催化系统，在生物医学研究中的进一步发展铺平了道路。

附：英文原文

Title: Rational Design of Conjugated Polymers for Photocatalytic CO2 Reduction: Towards Localized CO Production and Macrophage Polarization

Author: Chuanwei Zhu, Junjie Cheng, Hongrui Lin, Zhiwen Yang, Yiming Huang, Fengting Lv, Haotian Bai, Shu Wang

Issue&Volume: August 15, 2024

Abstract: Light presents substantial potential in disease treatment, where the development of efficient photocatalysts could enhance the utilization of photocatalytic systems in biomedicine. Here, we devised a novel approach to designing and synthesizing photocatalysts of conjugated polymers for photocatalytic CO2 reduction, relying on a multiple linear regression model built with theoretically calculated descriptors. We established a logarithmic relationship between molecular structure and CO yield and identified the poly(fluorene-co-thiophene) deviant (PFT) as the optimal one. PFT excited a CO regeneration ratio of 231 nmol h–1 in acetonitrile and 46 nmol h–1 in an aqueous solution with a reaction selectivity of 88%. Further advancements were made through the development of liposomes encapsulating PFT for targeted macrophage delivery. By distributing PFT on the liposome membranes, our constructed photocatalytic system efficiently generated CO in situ from surrounding CO2. This localized CO production served as an endogenous signaling molecule, promoting the desirable polarization of macrophages from the M1 to M2 phenotype. Consequently, the M2 cells reduced the secretion of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β). We also demonstrated the efficacy of our system in treating lipopolysaccharide-induced inflammation of cardiomyocytes under white light irradiation. Moreover, our research provides a comprehensive understanding of the intricate processes involved in CO2 reduction by a combination of theoretical calculations and experimental techniques including transient absorption, femtosecond ultrafast spectroscopy, and in situ infrared spectroscopy. These findings pave the way for further advancements of conjugated polymers and photocatalytic systems in biomedical investigation.

DOI: 10.1021/jacs.4c04980

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c04980