Positron emission tomography guided synergistic treatment of melanoma using multifunctional zirconium-hematoporphyrin nanosonosensitizers.

Sonodynamic therapy (SDT) has emerged as a useful approach for tumor treatment. However, its widespread application is impeded by poor pharmacokinetics of existing sonosensitizers. Here we developed a metal-organic nanoplatform, wherein a small-molecule sonosensitizer (hematoporphyrin monomethyl ether, HMME) was ingeniously coordinated with zirconium, resulting in a multifunctional nanosonosensitizer termed Zr-HMME. Through post-synthetic modifications involving PEGylation and tumor-targeting peptide (F3) linkage, a nanoplatform capable of homing on melanoma was produced, which could elicit robust immune responses to suppress tumor lung metastasis in the host organism. Importantly, after seamless incorporation of positron-emitting 89Zr into this nanosonosensitizer, positron emission tomography (PET) could be used to monitor its in vivo pharmacokinetics. PET imaging studies revealed that this nanoplatform exhibited potent tumor accumulation and strong in vivo stability. Using intrinsic fluorescence from HMME, a dual-modal diagnostic capability (fluorescence and PET) was confirmed for this nanosonosensitizer. In addition, the mechanisms of how this nanoplatform interacted with immune system were also investigated. The collective data proved that the coordination structure between small-molecule drug cargos and metals may enhance the functions of each other while mitigating their weaknesses. This straightforward approach can expand the potential applications of suitable drug molecules.

Structure prediction of epitaxial inorganic interfaces by lattice and surface matching with Ogre.

We present a new version of the Ogre open source Python package with the capability to perform structure prediction of epitaxial inorganic interfaces by lattice and surface matching. In the lattice matching step, a scan over combinations of substrate and film Miller indices is performed to identify the domain-matched interfaces with the lowest mismatch. Subsequently, surface matching is conducted by Bayesian optimization to find the optimal interfacial distance and in-plane registry between the substrate and the film. For the objective function, a geometric score function is proposed based on the overlap and empty space between atomic spheres at the interface. The score function reproduces the results of density functional theory (DFT) at a fraction of the computational cost. The optimized interfaces are pre-ranked using a score function based on the similarity of the atomic environment at the interface to the bulk environment. Final ranking of the top candidate structures is performed with DFT. Ogre streamlines DFT calculations of interface energies and electronic properties by automating the construction of interface models. The application of Ogre is demonstrated for two interfaces of interest for quantum computing and spintronics, Al/InAs and Fe/InSb.

Ogre: A Python package for molecular crystal surface generation with applications to surface energy and crystal habit prediction.

We present Ogre, an open-source code for generating surface slab models from bulk molecular crystal structures. Ogre is written in Python and interfaces with the FHI-aims code to calculate surface energies at the level of density functional theory (DFT). The input of Ogre is the geometry of the bulk molecular crystal. The surface is cleaved from the bulk structure with the molecules on the surface kept intact. A slab model is constructed according to the user specifications for the number of molecular layers and the length of the vacuum region. Ogre automatically identifies all symmetrically unique surfaces for the user-specified Miller indices and detects all possible surface terminations. Ogre includes utilities to analyze the surface energy convergence and Wulff shape of the molecular crystal. We present the application of Ogre to three representative molecular crystals: the pharmaceutical aspirin, the organic semiconductor tetracene, and the energetic material HMX. The equilibrium crystal shapes predicted by Ogre are in agreement with experimentally grown crystals, demonstrating that DFT produces satisfactory predictions of the crystal habit for diverse classes of molecular crystals.

Ultrathin Co3O4 Layers Realizing Optimized CO2 Electroreduction to Formate.

Electroreduction of CO2 into hydrocarbons could contribute to alleviating energy crisis and global warming. However, conventional electrocatalysts usually suffer from low energetic efficiency and poor durability. Herein, atomic layers for transition-metal oxides are proposed to address these problems through offering an ultralarge fraction of active sites, high electronic conductivity, and superior structural stability. As a prototype, 1.72 and 3.51 nm thick Co3O4 layers were synthesized through a fast-heating strategy. The atomic thickness endowed Co3O4 with abundant active sites, ensuring a large CO2 adsorption amount. The increased and more dispersed charge density near Fermi level allowed for enhanced electronic conductivity. The 1.72 nm thick Co3O4 layers showed over 1.5 and 20 times higher electrocatalytic activity than 3.51 nm thick Co3O4 layers and bulk counterpart, respectively. Also, 1.72 nm thick Co3O4 layers showed formate Faradaic efficiency of over 60% in 20 h.