Sonodynamic therapy (SDT) triggered by ultrasound (US) has attracted increasing attention owing to its abilities to overcome critical limitations including low tissue‐penetration depth and phototoxicity in photodynamic therapy. Herein, the design of a new type of sonosensitizer is revealed, namely, ultrasmall oxygen‐deficient bimetallic oxide MnWOX nanoparticles, for multimodal imaging‐guided enhanced SDT against cancer. As‐made MnWOX nanoparticles with poly(ethylene glycol) (PEG) modification show high physiological stability and biocompatibility. Interestingly, such MnWOX‐PEG nanoparticles exhibit highly efficient US‐triggered production of 1O2 and •OH, higher than that of previously reported sonosensitizers (e.g., protoporphyrin IX and titanium dioxide), because the oxygen‐deficient structure of MnWOX serves as an electron trap site to prevent electron–hole recombination. The glutathione depletion capability of MnWOX‐PEG can also further favor SDT‐triggered cancer cell killing. With efficient tumor homing as illustrated by computer tomography and magnetic resonance imaging, MnWOX‐PEG enables effective destruction of mouse tumors under US stimulation. After accomplishing its therapeutic functions, MnWOX‐PEG can be metabolized by the mouse body without any long‐term toxicity. Herein, a new type of sono‐sensitizing agent with high SDT efficacy, multimodal imaging functions, and rapid clearance is presented, an agent which is promising for noninvasive SDT cancer treatment.

No abstract

Plenty of thin‐film solar cell technologies using organic materials have been developed to alleviate energy shortages. As developing devices for solar energy applications, artificial photosynthesis is a trend inspired from natural photosynthesis. Although the sophisticated system that exists in nature is fascinating, the development of photovoltaic devices focusing on the usage of natural chlorophylls has been quite limited, compared with the application of other counterparts such as artificial porphyrins or phthalocyanines. Herein, the development of semisynthetic chlorophyll derivatives as functional materials for solar cells are focused on. (Bacterio)chlorins possessing a carboxylic acid moiety as a binding site to semiconductors are synthesized to improve the efficiencies of dye‐sensitized solar cells, which are now leading to another application: photocatalysts for hydrogen evolution. In contrast, derivatives without a carboxy group can be applied to organic solar cells. As for the application for perovskite solar cells, self‐assembling aggregates of a kind of derivatives are proven to be suitable as hole‐transporting materials. In addition, a new type of solid‐state biosolar cells is proposed, in which chlorophyll derivatives act solely as the photoactive materials. This Report can enlarge the scope of advanced functional materials in the field of solar energy applications.

As one of the most promising biomaterials, injectable self-healing hydrogels have found broad applications in a number of fields such as local drug delivery. However, controlled release of drugs in hydrogels is still difficult to realize up to now. Here, we report a novel photo-degradable injectable self-healing hydrogel based on the hydrophobic interaction of a biocompatible four-arms star polymer, poly(ethylene glycol)-b-poly(γ-o-nitrobenzyl-l-glutamate). The hydrophobic interaction between poly(γ-o-nitrobenzyl-l-glutamate) not only connects poly(ethylene glycol)-b-poly(γ-o-nitrobenzyl-l-glutamate) together with a crosslink but also provides a hydrophobic domain to encapsulate hydrophobic pharmaceuticals such as doxorubicin (DOX). Due to the dynamic character of the hydrophobic interaction, the hydrogel exhibits excellent injectable and self-healing ability. In particular, the photolabile o-nitribenzyl ester group is cleaved under UV irradiation. As a result, the hydrophobic domain transforms into the hydrophilic one and the embedded DOX is released effectively. An increasing release ratio of DOX dramatically enhances the apoptosis ratio of HeLa cells. We expect these attractive properties may be beneficial to practical applications of the hydrogel as an effective local drug delivery means in a truly physiological environment.

The power conversion efficiency (PCE) of chlorophyll (Chl)-based organic solar cells (OSCs) is generally about 2%. Herein, a Chl-a derivative (CHL) and [6,6]-phenyl-C 71 -butyric acid methyl ester (PC 71 BM) are successfully used to fabricate Chl-based OSCs with PCE over 5%. Two different preparation methods are used to prepare the active layer: 1) two-step spin-coating the self-aggregated CHL and PC 71 BM solutions sequentially and 2) one-step spin-coating the solution of CHL:PC 71 BM blends, forming the "bilayer" (BL) and traditional bulk heterojunction (BHJ) configurations, respectively. Based on the aforementioned two kinds of active-layer preparation methods, both inverted and regular types of OSCs are successfully investigated. All four types of devices work normally, which is likely due to the ambipolar characteristics of the CHL aggregate. Unexpectedly, the BL-based devices yield PCEs of 5.17% for the regular type and 5.19% for the inverted type, which are higher than those of the BHJ-based devices (3.96% for the regular type and 3.50% for the inverted type). The main improvement in PCEs of BL-based devices comes from the enhanced short-circuit currents, which is due to the decreased charge transfer resistance and enlarged photocurrent contribution of PC 71 BM as well as slightly enhanced electron and hole mobilities.