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Although magnetism undoubtedly influences life on Earth, the science behind biological magnetic sensing is largely a mystery, and it has proved challenging, especially in the life sciences, to harness the interactions of magnetic fields (MFs) with matter to achieve specific ends. Using the well-established radical pair (RP) mechanism, we here demonstrate a bottom-up strategy for the exploitation of MF effects in living cells by translating knowledge from studies of RP reactions performed in vitro. We found an unprecedented MF dependence of the reactivity of singlet oxygen (1O2) towards electron-rich substrates (S) such as anthracene, lipids and iodide, in which [ S ˙+ O2˙−] RPs are formed as a basis for MFs influencing molecular redox events in biological systems. The close similarity of the observed MF effects on the biologically relevant process of lipid peroxidation in solution, in membrane mimics and in living cells, shows that MFs can reliably be used to manipulate 1O2-induced cytotoxicity and cell-apoptosis-related protein expression. These findings led to a 'proof-of-concept' study on MF-assisted photodynamic therapy in vivo , highlighting the potential of MFs as a non-invasive tool for controlling cellular events. [ABSTRACT FROM AUTHOR]

The conversion of CO2 into fuels or commodity chemicals by electrochemical or photochemical reduction is a promising strategy to relieve the ongoing energy crisis and increasing environmental pollution. Inspired by naturally occurring bimetalloenzymes, we have designed hetero–bimetallic CO2 reduction catalysts (FeM) that involve linking an iron tetraphenylporphyrin (FeP) with a tripyridylamine (TPA) moiety, which provides a distal chelating site for Cu2+ or Zn2+. We found that the introduction of Cu2+ or Zn2+ to FeP greatly enhances its efficiency as a catalyst for the electrochemical reduction of CO2. To gain insights into the observed synergistic effect, we performed mechanistic studies together with density functional theory (DFT) calculations. Our results show that Cu2+ or Zn2+ activates CO2 towards reduction due to its Lewis acidity; it also functions as an oxo acceptor from CO2. FeM also functions as an efficient catalyst for the visible‐light‐driven reduction of CO2 using either [Ru(bpy)3] Cl2 or fac‐Ir(ppy)3 (where bpy=2,2'‐bipyridine, ppy=2‐phenylpyridine) as photosensitizer and 1,3‐dimethyl‐2‐phenyl‐2,3‐dihydro‐1H‐benzo[d] imidazole (BIH) as sacrificial reductant. Again, the catalytic efficiency is enhanced by the presence of Cu2+ or Zn2+. Our results provide a general strategy for the design of a series of hetero‐bimetallic catalysts for the reduction of CO2. [ABSTRACT FROM AUTHOR]

Molecular phototheranostics as an emerging field of modern precision medicine has recently attracted increasing research attention owing to non‐invasiveness, high precision, and controllable nature of light. In this work, we reported promising gadolinium (Gd3+) porphyrinoids as phototheranostic agents for magnetic resonance imaging (MRI) and photodynamic therapy (PDT). The synthesized Gd‐1‐4‐Glu featured with meso‐glycosylation and β‐lactonization to endow good biocompatibility and improved photophysical properties. In particular, β‐lactonization of glycosylated Gd3+ porphyrinoids substantially red‐shifted Q band absorption to near‐infrared (NIR) region and boosted generation of reactive oxygen species including 1O2, and some radical species that engaged in both type II and type I PDT pathways. In addition, the number and regioisomerism of β‐oxazolone moieties was observed to play an essential role in improving longitude relaxivity (r1) of Gd‐1‐4‐Glu of up to 4.3±0.2 mM−1s−1 by affecting environmental water exchange. Taking Gd‐4‐Glu as a promising complex, we further achieved real‐time T1‐weighted MRI and PDT on HeLa tumour mice in vivo, revealing the appealing potential of Gd3+ porphyrinoids in phototheranostics. [ABSTRACT FROM AUTHOR]