Nanomedicines capable of smart operation at the targeted site have the potential to achieve the utmost therapeutic benefits. Providing nanomedicines that respond to endogenous stimuli with an additional external trigger may improve the spatiotemporal control of their functions, while avoiding drawbacks from their inherent tissue distribution. Herein, by exploiting the permeabilization of endosomes induced by photosensitizer agents upon light irradiation, we complemented the intracellular action of polymeric micelles incorporating camptothecin (CPT), which can sharply release the loaded drug in response to the reductive conditions of the cytosol, as an effective strategy for precisely controlling the function of these nanomedicines in vivo, while advancing toward a light-activated chemotherapy. These camptothecin-loaded micelles (CPT/m) were stable in the bloodstream, with minimal drug release in extracellular conditions, leading to prolonged blood circulation and high accumulation in xenografts of rat urothelial carcinoma. With the induction of endosomal permeabilization with the clinically approved photosensitizer, Photofrin, the CPT/m escaped from the endocytic vesicles of cancer cells into the cytosol, as confirmed both in vitro and in vivo by real-time confocal laser microscopies, accelerating the drug release from the micelles only in the irradiated tissues. This spatiotemporal switch significantly enhanced the in vivo antitumor efficacy of CPT/m without eliciting any toxicity, even at a dose 10-fold higher than the maximum tolerated dose of free CPT. Our results indicate the potential of reduction-sensitive drug-loaded polymeric micelles for developing safe chemotherapies after activation by remote triggers, such as light, which are capable of permeabilizing endosomal compartments.

A polymer solar cell based on poly(3-hexylthiophene) (P3HT)/iron disulfide (FeS2) nanocrystal (NC) hybrid is presented. The FeS2 NCs of 10 nm in diameter were homogeneously blended with P3HT to form an active layer of a solar cell. An extended red light harvesting up to 900 nm resulting from the NCs in the device has been demonstrated, compared to a typical absorption edge of 650 nm of a pristine P3HT. The environmentally friendly and low-cost FeS2 NCs can be used as a promising candidate for an acceptor in the polymer solar cell device application with an enhanced photovoltaic response in the extended red light region.

Hydrogen is considered as sustainable and environmentally friendly energy for global energy demands in the future. Here a Co-FeS catalyst with surface phosphide doping (P/Co-FeS ) for hydrogen evolution reaction (HER) in acidic solutions is developed. The P/Co-FeS exhibits superior HER electrochemical performance with overpotential of -90 mV at 100 mA cm and Tafel slope of 41 mV/decade and excellent durability.

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New ternary metal nanocrystals of Fe1 - x PtM x (M = Ru3+, Sn2+, or Ni2+) were synthesized by chemical transformation from FePt nanocrystals using a cation redox reaction in a solution. The structure and composition of resulting nanocrystals were characterized by high-resolution transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and X-ray photoemission spectroscopy (XPS). Moreover, X-ray absorption near-edge spectroscopy (XANES) was employed to confirm the chemical transformation from FePt to Fe1 - x PtRu x nanocrystals. The analyses of extended X-ray absorption find structure (EXAFS) revealed the detailed binding structures and coordination numbers of both FePt and Fe1 - x PtRu x nanocrystals. The results suggested that iron atoms of FePt lattices were oxidized to be Fe2+ and Fe3+ ions and were replaced by ruthenium atoms from the reduction of Ru3+ ions in solution to form Fe1 - x PtRu x lattices. Our method has opened a new route to easily and rapidly prepare a solid-solution type of ternary metal nanocrystals for catalytic applications.