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Near-infrared (NIR) controlled drug delivery systems have drawn a lot of attention throughout the past few decades due to the deep penetration depth and comparatively minor side effects of the stimulus. In this study, we introduce an innovative approach for gastric cancer treatment by combining photothermal infrared-sensitive gold nanorods (AuNRs) with a conjugated microporous polymer (CMP) to create a drug delivery system tailored for transporting the cytostatic drug 5-fluorouracil (5-FU). CMPs are fully conjugated networks with high internal surface areas that can be precisely tailored to the adsorption and transport of active compounds through the right choice of chemical functionalities. By incorporation of surfactant-stabilized AuNRs into the CMP synthesis in dimethylformamide (DMF) the surfactant shell is destabilized and subsequently replaced by the CMP. Particularly, low initial surfactant concentrations led to uniform distribution of the AuNRs in the polymer matrix. Importantly, the integrated AuNRs maintain their plasmonic properties, as was confirmed via electron energy loss spectroscopy. Therefore, the significant photothermal properties are translated to the hybrid material as shown in a proof-of-principle experiment. Further, in an approximated gastric environment, 5-FU release studies were conducted with and without NIR stimulus. Thereby it was observed that increased Brownian motion due to the NIR irradiation not only accelerates the release but also increases the total released amount by influencing the adsorption-desorption equilibrium. This remarkable level of control of the release process underlines the immense potential of this hybrid material for precise and targeted drug delivery.

Solar-driven production of fuels such as hydrogen, hydrocarbons, and ammonia using semiconducting photocatalysts has the potential to be a sustainable alternative to current chemical processes. In recent years, silicon (Si) nanostructures have been recognized as a promising photocatalyst for hydrogen generation and organic oxidation reactions owing to its abundance, biocompatibility, and cost. While bulk Si has been studied extensively, on the nanoscale, plenty of opportunities exist to understand and engineer optimally performing Si photocatalysts. This perspective will highlight key results on the use of Si nanostructures for photocatalytic H 2 production, CO 2 reduction via light and heat-driven chemical looping, and current challenges in utilizing it for fuel-forming reactions. A brief guide on how these challenges can be addressed in the future and other unexplored questions that remain in the field are also discussed., Competing Interests: The authors declare no competing interests., (© 2023 The Author(s).)

An advanced light-induced avenue to monodisperse sequence-defined linear macromolecules via a unique photochemical protocol is presented that does not require any protection-group chemistry. Starting from a symmetrical core unit, precision macromolecules with molecular weights up to 6257.10 g mol -1 are obtained via a two-monomer system: a monomer unit carrying a pyrene functionalized visible light responsive tetrazole and a photo-caged UV responsive diene, enabling an iterative approach for chain growth; and a monomer unit equipped with a carboxylic acid and a fumarate. Both light-induced chain growth reactions are carried out in a λ-orthogonal fashion, exciting the respective photosensitive group selectively and thus avoiding protecting chemistry. Characterization of each sequence-defined chain (size-exclusion chromatography (SEC), high-resolution electrospray ionization mass spectrometry (ESI-MS), and NMR spectroscopy), confirms the precision nature of the macromolecules., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)