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Competing Interests: Conflict of interest The authors declare that they have no conflict of interest.

One of the key challenges in the development of RNA interference-based cancer therapy is the lack of an efficient delivery system for synthetic small interfering RNAs (siRNAs) that would enable efficient uptake by tumor cells and allow for significant knockdown of a target transcript in vivo. Here, we describe a micelleplex system based on an amphiphilic and cationic triblock copolymer, which can systemically deliver siRNA targeting the acid ceramidase (AC) gene for cancer therapy. This triblock copolymer, consisting of monomethoxy poly(ethylene glycol), poly(ε-caprolactone) and poly(2-aminoethyl ethylene phosphate), self-assembles into micellar nanoparticles (MNPs) in aqueous solution with an average diameter of 60 nm and a zeta potential of approximately 48 mV. The resulting micelleplex, formed by the interaction of MNPs and siRNA, was effectively internalized by BT474 breast cancer cells and siRNA was subsequently released, resulting in significant gene knockdown. This effect was demonstrated by significant down-regulation of luciferase expression in BT474-luciferase cells which stably express luciferase, and suppression of AC expression in BT474 cells at both the transcriptional and protein level, following delivery of specific siRNAs by the micelleplex. Furthermore, a micelleplex carrying siRNA targeting the AC (micelleplex(siAC)) gene was found to induce remarkable apoptosis and reduce the proliferation of cancer cells. Systemic delivery of micelleplex(siAC) significantly inhibited tumor growth in a BT474 xenograft murine model, with depressed expression of AC and no positive activation of the innate immune response, suggesting therapeutic promise for micelleplex siRNA delivery in cancer therapy., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Surface modification is often needed in tissue engineering to enhance the interaction between cells and synthetic materials and improve the cytocompatibility and cellular functions. In this study, block copolymers of poly(L-lactic acid) and poly(ethyl ethylene phosphate) (PLLA-b-PEEP) were synthesized and used to modify the PLLA surface via a spin-coating process, to understand whether surface modification with polyphosphoester-based polymer will be osteoinductive for potential bone tissue engineering applications. X-ray photoelectron spectra measurements revealed that phosphorus atomic compositions after surface modification increased from 2.09% to 4.39% with increasing PEEP length of PLLA-b-PEEP from 58 to 224 units, which also led to a more hydrophilic surface property compared with unmodified PLLA. The initial osteoblast attachment and proliferation on the modified surfaces were significantly enhanced. Moreover, cellular alkaline phosphatase activity and mineral calcium depositions were also promoted by PEEP modification. The gene expression determined by reverse transcription polymerase chain reaction further revealed that type I collagen and osteocalcin expression were upregulated in osteoblasts cultured on the modified surfaces, indicating that PEEP modification might be potentially osteoinductive and favorable for further application in bone tissue engineering.

A novel amphiphilic and cationic triblock copolymer consisting of monomethoxy poly(ethylene glycol), poly(epsilon-caprolactone) (PCL) and poly(2-aminoethyl ethylene phosphate) denoted as mPEG(45)-b-PCL(100)-b-PPEEA(12) was designed and synthesized for siRNA delivery. The copolymers were well characterized by (1)H NMR spectroscopy and gel permeation chromatography. Micelle nanoparticles' (MNPs) formation of this amphiphilic copolymer in aqueous solution was studied by dynamic light scattering, transmission electron microscopy and fluorescence technique. MNPs took uniform spherical morphology with zeta potential of around 45 mV and were stabilized by hydrophobic-hydrophobic interaction in the PCL core, exhibiting the critical micelle concentration at 2.7 x 10(-3) mg/mL. Such MNPs allowed siRNA loading post nanoparticle formation without change in uniformity. The average diameter of nanoparticles after siRNA binding ranged from 98 to 125 nm depending on N/P ratios. The siRNA loaded nanoparticles can be effectively internalized and subsequently release siRNA in HEK293 cells, resulting in significant gene knockdown activities, which was demonstrated by delivering two siRNAs targeting green fluorescence protein (GFP). It effectively silenced GFP expression in 40-70% GFP-expressed HEK293 cells and it was observed that higher N/P ratio resulted in more effective silence which was likely due to better cell internalization at higher N/P ratio. MTT assay demonstrated that neither MNPs themselves nor siRNA loaded MNPs showed cytotoxicity even at high concentrations. Such cationic MNPs made from biocompatible and biodegradable polymers are promising for siRNA delivery.

A series of novel amphiphilic triblock copolymers of poly(ethyl ethylene phosphate) and poly(-caprolactone) (PEEP-PCL-PEEP) with various PEEP and PCL block lengths were synthesized and characterized. These triblock copolymers formed micelles composed of a hydrophobic core of poly(-caprolactone) (PCL) and a hydrophilic shell of poly(ethyl ethylene phosphate) (PEEP) in aqueous solution. The micelle morphology was spherical, determined by transmission electron microscopy. It was found that the size and critical micelle concentration values of the micelles depended on both hydrophobic PCL block length and PEEP hydrophilic block length. The in vitro degradation characteristics of the triblock copolymers were investigated in micellar form, showing that these copolymers were completely biodegradable under enzymatic catalysis of Pseudomonas lipase and phosphodiesterase I. These triblock copolymers were used for paclitaxel (PTX) encapsulation to demonstrate the potential in drug delivery. PTX was successfully loaded into the micelles, and the in vitro release profile was found to be correlative to the polymer composition. These biodegradable triblock copolymer micelles are potential as novel carriers for hydrophobic drug delivery.

Traditional artificial skin gels often only focuses on a single perspective and overlooks the necessity of multidimensional synergistic design for sensitivity enhancement. To address these problems, the innovative introduction of dual solvents on the surface of polyacrylamide/sodium alginate gel induces to the transformation of supramolecular interactions including ion coordination, crystalline alcohol, and phase separation, synergistically achieving adjustable wrinkle wavelengths (304.2 ± 19.9 to 2393.5 ± 95.9 µm) and modulated chemical compositions with tunable moduli (87.5 ± 3.3 to 157.6 ± 3.7 kPa). This flexible strategy allows the construction of long‐range ordered wrinkled microstructures of three‐dimensional surfaces and complex morphologies. Meanwhile, the bridge effect induced by crystalline alcohols directs the insertion of ethanol molecules into the polymer chains, effectively reducing intramolecular friction. Benefiting from the small wavelength and low modulus dominated by crystalline alcohol, the wrinkled gel exhibits extremely high sensitivity of 164 kPa−1 (<0.5 kPa) and wide detection range (44.3 kPa). The wrinkled gel remains stable high sensitive to detect micro‐ and large stress, tactile perception, and human motion behaviors. This work proposes a new strategy for constructing highly sensitive bioinspired skin from multiple dimensions, showing broad application prospects in the fields of bioengineering and behavioral cognition. [ABSTRACT FROM AUTHOR]

Efficient and scalable production of high‐quality and processable two‐dimensional (2D) polymers are highly desired but have not yet been reported. Herein, we demonstrate a convenient noncovalent functionalization strategy for producing highly uniform, aqueous processable and semiconducting 2D triazine polymers. Experimental and theoretical analysis reveal that the aromatic amphiphilic 1‐pyrenebutyrate can adsorb and intercalate into the interlayer of bulk crystalline covalent triazine framework (CTF) through noncovalent π‐π stacking interaction between the pyrene moiety and the porous basal plane of 2D triazine polymer layer, which greatly facilitate the exfoliation of CTF in water in large scale. The as‐prepared highly water‐dispersible single‐layer/few‐layer 2D triazine polymer nanosheets can be easily processed into ultralight aerogels with a density of 5–15 mg cm−3, which can be further shaped into mechanically strong films upon simple compression. This noncovalent functionalization not only improve the dispersibility and processability of 2D triazine polymer, but also optimize its band structure and promote the photogenerated carrier separation via an interesting surface molecule doping effect, thus resulting in a remarkable photocatalytic hydrogen evolution rate of 1249 μmol h−1 (24980 μmol g−1 h−1) and apparent quantum efficiency up to 27.2 % at 420 nm for the 2D triazine polymer, outperforming most metal‐free photocatalysts ever reported. [ABSTRACT FROM AUTHOR]

In their Research Article (e202301865), Yuxi Xu et al. demonstrate that the obtained crystalline ultrathin 2D triazine polymer nanosheets can not only be assembled into ultralight and mechanically strong macroscopic porous aerogels, but also show a new surface molecule doping effect to significantly improve the photocatalytic water splitting activity. In their Research Article (e202301865), Yuxi Xu et al. demonstrate that the obtained crystalline ultrathin 2D triazine polymer nanosheets can not only be assembled into ultralight and mechanically strong macroscopic porous aerogels, but also show a new surface molecule doping effect to significantly improve the photocatalytic water splitting activity. Cover Picture: Aqueous Processable Two-Dimensional Triazine Polymers with Superior Photocatalytic Properties (Angew. [Extracted from the article]

[Display omitted] • One-step synthesis of polymer dot from monomer is proposed. • A new nitrogen-doped polymer nanodot is proposed. • N-PD is the most efficient one than reported carbon dots-based corrosion inhibitors. • The mechanism of adsorption and corrosion resistance is demonstrated. Carbon dots as a specific type of carbon material require the connection of experiment to theory, exploration of new application, and development of new material. Here we present a new nitrogen-doped polymer nanodots (N-PDs) from 3,4-dihydroxy-L-phenylalanine (L-DOPA) via the one-step synthesis of simultaneous self-polymerization and carbonization process. This water-dispersible N-PDs, composed of poly-L-DOPA aggregates and embedded nitrogen-doped graphene patches, shows the zero-dimensional structure with an average diameter of 2.06 nm. In-depth investigation of the inhibition effect of as-prepared N-PDs demonstrates that N-PDs can suppress the oxygen and chloride corrosion of mild steel in extremely acidic condition through the dual effect of adsorption/assembly onto metal surface as a passivation film and strong covalent bonding with iron, resulting in an inhibition efficiency of 97.95% at the concentration higher than 200 mg/L within 6 h, the most efficient reported for carbon dots-based corrosion inhibitors. Furthermore, density-functional-theory calculations clearly reveal that the atoms present in unsaturated bonds of N-PDs play a dominant role in strengthening the interaction between corrosion inhibitor and metal substrate, which gives rise to the stable and homogeneous adsorption of N-PDs and then the effective protection for metal substrate against corrosion. [ABSTRACT FROM AUTHOR]

Back Cover: Rapid, Ordered Polymerization of Crystalline Semiconducting Covalent Triazine Frameworks (Angew. 2D ordered polymerization, 2D polymers, covalent triazine frameworks, large-scale synthesis, photocatalysis Keywords: 2D ordered polymerization; 2D polymers; covalent triazine frameworks; large-scale synthesis; photocatalysis EN 2D ordered polymerization 2D polymers covalent triazine frameworks large-scale synthesis photocatalysis 1 1 1 01/18/22 20220121 NES 220121 B The rapid synthesis b of crystalline semiconducting covalent triazine frameworks (CTFs) through a two-dimensional (2D) ordered polymerization mechanism is described by Yuxi Xu and co-workers in their Communication (e202113926). [Extracted from the article]

Rücktitelbild: Rapid, Ordered Polymerization of Crystalline Semiconducting Covalent Triazine Frameworks (Angew. 2D ordered polymerization, 2D polymers, covalent triazine frameworks, large-scale synthesis, photocatalysis Keywords: 2D ordered polymerization; 2D polymers; covalent triazine frameworks; large-scale synthesis; photocatalysis EN 2D ordered polymerization 2D polymers covalent triazine frameworks large-scale synthesis photocatalysis 1 1 1 01/18/22 20220121 NES 220121 B Die schnelle Synthese b von kristallinen halbleitenden kovalenten Triazin-Gerüststrukturen (CTFs) durch einen zweidimensionalen geordneten Polymerisationsmechanismus wird von Yuxi Xu et al. in ihrer Zuschrift demonstriert (e202113926). [Extracted from the article]

Two star-shaped multi-triphenylamine derivatives 1 and 2 were prepared, where 2 has an additional phenyl unit between a pyrene core and surrounding triphenylamine units. The oxidative electropolymerization of 1 and 2 occurred smoothly to give thin films of polymers P1 and P2. The electrochemistry and spectroelectrochemistry of P1 and P2 were examined, showing two-step absorption spectral changes in the near-infrared region. The electrochromic properties, including contrast ratio, response time, and cyclic stability of P1 and P2 were investigated and compared. Thin film of P2 displays slightly better electrochromic performance than P1, with a contrast ratio of 45% at 1475 nm being achieved. [ABSTRACT FROM AUTHOR]