Hypoxia- and singlet oxygen-responsive chemo-photodynamic Micelles featured with glutathione depletion and aldehyde production.

Triggered drug release from anti-tumor nanomedicine is an efficient approach to address the dilemma of systemic nanocarrier stability and on-demand drug liberation in tumor sites. Combinational drug delivery has been a useful means to enhance antitumor efficacy and reduce adverse effects. We report a multifunctional micelle for dually hypoxia- and singlet oxygen-responsive integration of chemotherapy and photodynamic therapy.

Photocontrolled reversible conversion of a lamellar supramolecular assembly based on cucurbiturils and a naphthalenediimide derivative.

Lamellar and helical supramolecular assemblies were constructed using cucurbiturils and a naphthalenediimide derivative. More interestingly, the formation of the lamellar assembly could be reversibly photocontrolled via competitive binding with α-cyclodextrin and water-soluble azobenzene.

Conversion of an amide to a high-energy thioester by Staphylococcus aureus sortase A is powered by variable binding affinity for calcium.

Thioesters are key intermediates in biology, which often are generated from less energy-rich amide precursors. Staphylococcus aureus sortase A (SrtA) is an enzyme widely used in biotechnology for peptide ligation. The reaction proceeds in two steps, where the first step involves the conversion of an amide bond of substrate peptide into a thioester intermediate with the enzyme.

Seeing the fate and mechanism of stem cells in treatment of ionizing radiation-induced injury using highly near-infrared emissive AIE dots.

Ionizing radiation-induced skin injury is a common and severe side effect of radiotherapy suffered by cancer patients. Although the therapy using stem cells has been demonstrated to be effective, fully grasping their role in the repair of radiation-induced skin damage remains challenging owing to the lack of highly reliable cell trackers. Herein, we report the design and synthesis of a highly near-infrared emissive organic nanodots with aggregation-induced emission (AIE) characteristic, which give excellent performance in seeing the fate and regenerative mechanism of adipose-derived stem cells (ADSCs) in treatment of radiation-induced skin injury.

Fast naked-eye detection of zinc ions by molecular assembly-assisted polymerization of diacetylene.

Portable visual detection systems for environmental monitoring or diagnostic purposes are eagerly anticipated in low-resource settings. Inexpensive device requirements and visualization are key challenges for the development of any portable analysis system. We report herein a new strategy for developing portable rapid ion detection technology by the coupling of topochemical polymerization and supramolecular (SM) self-assembly.

A Hierarchical Silver-Nanowire-Graphene Host Enabling Ultrahigh Rates and Superior Long-Term Cycling of Lithium-Metal Composite Anodes.

Metallic lithium (Li) is a promising anode for next-generation high-energy-density batteries, but its applications are still hampered due to the limited charging/discharging rate and poor cycling performance. Here, a hierarchical 3D porous architecture is designed with a binary network of continuous silver nanowires assembled on an interconnected 3D graphene skeleton as the host for Li-metal composite anodes, which offers a significant boost in both charging/discharging rates and long-term cycling performance for Li-metal batteries. This unique hierarchical binary network structure in conjunction with optimized material combination provides ultrafast, continuous, and smooth electron transportation channel and non-nucleation barrier sites to direct and confine Li deposition.

C -Symmetric Bicyclic Bisborane Catalysts: Kinetic or Thermodynamic Products of a Reversible Hydroboration of Dienes.

We prepared a new class of chiral C -symmetric bicyclic bisborane catalysts by addition reactions of internal dienes with the Piers borane, HB(C F ) , and an analogue, HB(p-C F H) . The dependence of the addition pattern on the reaction temperature allowed us to selectively prepare two diastereomeric catalysts from a single diene precursor. The bisboranes prepared in situ exhibited excellent activity (turnover numbers up to 200 at -40 °C) and enantioselectivity (up to 95 % ee) in imine hydrogenation reactions.

From small deferiprone to macromolecular micelles: Self-assembly enhances iron chelation.

We report a self-assembly-based approach for improved iron chelation of small chelators. A model chelator, deferiprone (DFP) is covalently linked to amphiphilic poly(ethylene glycol)-polypeptide block copolymer that can assemble into micelles. The free DFP generally coordinates with iron in a ratiometric manner (3:1).

All-active antitumor micelles via triggered lipid peroxidation.

Traditional antitumor nanomedicines have been suffering from the poor tumor targeting (ca. 1%) by the enhanced permeability and retention (EPR) effect, and the low drug loading (<5%). It was postulated that engineering all-active nanoplatform could increase the therapeutic efficacy to enable the nanocarrier function as both vehicle and active ingredient.

Stable Superhydrophobic Ceramic-Based Carbon Nanotube Composite Desalination Membranes.

Membrane distillation (MD) is a promising process for the treatment of highly saline wastewaters. The central component of MD is a stable porous hydrophobic membrane with a large liquid-vapor interface for efficient water vapor transport. A key challenge for current polymeric or hydrophobically modified inorganic membranes is insufficient operating stability, resulting in some issues such as wetting, fouling, flux, and rejection decline.

Recent Advances in Designing High-Capacity Anode Nanomaterials for Li-Ion Batteries and Their Atomic-Scale Storage Mechanism Studies.

Lithium-ion batteries (LIBs) have been widely applied in portable electronics (laptops, mobile phones, etc.) as one of the most popular energy storage devices. Currently, much effort has been devoted to exploring alternative high-capacity anode materials and thus potentially constructing high-performance LIBs with higher energy/power density.

An arene-tethered silylene ligand enabling reversible dinitrogen binding to iron and catalytic silylation.

An arene-tethered silylene ligand, L (L = PhC(tBuN)2SiCH2C(tBu)NAr, Ar = 2,6-iPr2C6H3), allowed the synthesis of three-coordinate Fe(ii) silylamido and piano-stool Fe(0) dinitrogen complexes LFe[N(SiMe3)2]2 (3) and LFe-N2 (4), which not only exhibit interesting bonding but also enabled the catalytic silylation of N2 to yield N(SiMe3)3 under 1 atm of N2 at room temperature with high TONs.

Folic Acid Derived Hydrogel Enhances the Survival and Promotes Therapeutic Efficacy of iPS Cells for Acute Myocardial Infarction.

Stem cell therapy has obtained extensive consensus to be an effective method for post myocardial infarction (MI) intervention. Induced pluripotent stem (iPS) cells, which are able to differentiate into multiple cell types, have the potential to generate cardiovascular lineage cells for myocardial repair after ischemic damage, but their poor retention rate significantly hinders the therapeutic efficacy. In the present study, we developed a supramolecular hydrogel which is formed by the self-assembly of folic acid (FA)-modified peptide via a biocompatible method (glutathione reduction) and suitable for cell encapsulation and transplantation.

Imidazole-Bearing Polymeric Micelles for Enhanced Cellular Uptake, Rapid Endosomal Escape, and On-demand Cargo Release.

The complex design of multifunctional nanomedicine is beneficial to overcome the multiple biological barriers of drug delivery, but it also presents additional hurdles to clinical translation (e.g., scaling-up and quality control).

Alleviating the Liver Toxicity of Chemotherapy via pH-Responsive Hepatoprotective Prodrug Micelles.

Nanocarriers have been extensively utilized to enhance the anti-tumor performance of chemotherapy, but it is very challenging to eliminate the associated hepatotoxicity. This was due to the significant liver accumulation of cytotoxic drug-loaded nanocarriers as a consequence of systemic biodistribution. To address this, we report a novel type of nanocarrier that was made of hepatoprotective compound (oleanolic acid/OA) with a model drug (methotrexate/MTX) being physically encapsulated.

A Peptide-Based Supramolecular Hydrogel for Controlled Delivery of Amine Drugs.

Supramolecular hydrogels hold great promise for controlled drug delivery. Herein we report a supramolecular hydrogel based on a peptide bearing a terminal aldehyde. The hydrogel was prepared via an enzyme instructed self-assembly (EISA) process, and the resulting hydrogels showed ultra-stable properties in highly acidic or basic aqueous solutions.

Mechanistic insight into the singlet oxygen-triggered expansion of hypoxia-responsive polymeric micelles.

Nitroimidazole-bearing nanomedicine has been popular as a hypoxia-responsive platform for on-demand drug delivery. We report the singlet oxygen-responsive property of nitroimidazole-containing micelles and the corresponding reaction mechanism, which would pave the way for developing a dual hypoxia- and singlet oxygen-sensitive drug delivery nanoplatform based on a simple nitroimidazole moiety.

Self-template synthesis of double-layered porous nanotubes with spatially separated photoredox surfaces for efficient photocatalytic hydrogen production.

Improving charge carriers separation to achieve high photoconversion efficiency in heterogeneous photocatalysts is highly desirable. Herein, heterostructured ZnS@CdS double-layered porous nanotubes (PNTs), in which the spatially separated reduction and oxidation reaction sites lie on the outer and inner shell, respectively, are fabricated through a robust self-template conversion strategy. After selective photo-deposition of Ni and CoO as dual cocatalysts, Ni nanoparticles as electron collectors and reduction reaction sites are loaded on the outer shell, while CoO nanoparticles as hole collectors and oxidation reaction sites are loaded on the inner shells.

Total Synthesis of the Highly N-Methylated Peptide Jahanyne.

Total synthesis of jahanyne (1) was achieved from commercially available materials on a 38 mg scale. The Boc- N-Me- L-Val-OH fragment along with the HATU/DIPEA coupling condition was applied to avoid the diketopiperazine side reaction in solution phase synthesis.

Metal-Organic Frameworks Based on Multicenter-Bonded [M ] (M=Mn, Zn) Clusters with Cubic Aromaticity.

A new concept for constructing metal-organic frameworks (MOFs) based on multicenter-bonded [M ] (M=Mn, Zn) clusters with cubic aromaticity is discussed. In principle, intermolecular/intramolecular hydrogen-bonding, π-π stacking, coordinated covalent bonding and ionic bonding usually account for the structures of MOFs, and multicentered bonds generally exist in cation, anion, neutral and zwitterionic radicals, while rarely appear in MOFs. Meanwhile, aromaticity became one of the most vexing yet fascinating key concepts in chemistry since the proposition of the structure of benzene molecule in 1865.

Corannulene-Incorporated AIE Nanodots with Highly Suppressed Nonradiative Decay for Boosted Cancer Phototheranostics In Vivo.

Fluorescent nanoparticles (NPs) based on luminogens with aggregation-induced emission characteristic (AIEgens), namely AIE dots, have received wide attention because of their antiquenching attitude in emission and reactive oxygen species (ROS) generation when aggregated. However, few reports are available on how to control and optimize their fluorescence and ROS generation ability. Herein, it is reported that enhancing the intraparticle confined microenvironment is an effective approach to advanced AIE dots, permitting boosted cancer phototheranostics in vivo.

Hole Mobility Modulation in Single-Crystal Metal Phthalocyanines by Changing the Metal-π/π-π Interactions.

Weak intermolecular interactions in organic semiconducting molecular crystals play an important role in determining molecular packing and electronic properties. Single crystals of metal-free and metal phthalocyanines were synthesized to investigate how the coordination of the central metal atom affects their molecular packing and resultant electronic properties. Single-crystal field-effect transistors were made and showed a hole mobility order of ZnPc>MnPc>FePc>CoPc>CuPc>H Pc>NiPc.

Multifunctional Micelles Dually Responsive to Hypoxia and Singlet Oxygen: Enhanced Photodynamic Therapy via Interactively Triggered Photosensitizer Delivery.

Nanoparticulate antitumor photodynamic therapy (PDT) has been suffering from the limited dose accumulation in tumor. Herein, we report dually hypoxia- and singlet oxygen-responsive polymeric micelles to efficiently utilize the photosensitizer deposited in the disease site and hence facilely improve PDT's antitumor efficacy. Tailored methoxy poly(ethylene glycol)-azobenzene-poly(aspartic acid) copolymer conjugate with imidazole as the side chains was synthesized.

A Two-Dimensional Ruddlesden-Popper Perovskite Nanowire Laser Array based on Ultrafast Light-Harvesting Quantum Wells.

Miniaturized nanowire nanolasers of 3D perovskites feature a high gain coefficient; however, room-temperature optical gain and nanowire lasers from 2D layered perovskites have not been reported to date. A biomimetic approach is presented to construct an artificial ligh-harvesting system in mixed multiple quantum wells (QWs) of 2D-RPPs of (BA) (FA) Pb Br , achieving room-temperature ASE and nanowire (NW) lasing. Owing to the improvement of flexible and deformable characteristics provided by organic BA cation layers, high-density large-area NW laser arrays were fabricated with high photostability.

Distinguishing Diketopyrrolopyrrole Isomers in Single-Molecule Junctions via Reversible Stimuli-Responsive Quantum Interference.

Distinguishing structural isomers at the single-molecule level remains a challenge. We report the single-molecule recognition of two diketopyrrolopyrrole containing isomers (SDPP and SPPO) employing the mechanically controllable break junction technique. The single-molecule conductances of the two isomers are indistinguishable under normal conditions.