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Novel chiral monodentate phosphonite ligands with spirobiindane as a backbone were developed. The electron-withdrawing substituent on the P-phenyl ring of the phosphonite ligand significantly reduced the reactivity and enantioselectivity of the ligand.

The tuning effect of silyl protecting groups on the glycosylation reactivity of arabinofuranosyl phenyl thioglycoside donors is presented. Silyl ethers on the 3-, 5-, and 3,5-positions of the arabinofuranose ring are found to have an arming effect on the donor reactivity, whereas the cyclic 3,5-acetal type protecting groups reduce the reactivity. [ABSTRACT FROM AUTHOR]

We study the self-assembly of ordered nanostructures,that is,nanorings (NRs) and quantum dots (QDs), epitaxially grown on a polygonalcross-section nanowire (PCS-NW) using both theoretical and phase-fieldmodeling. Our studies show that, by increasing the PCS-NW size, transitionsfrom ordered NRs to ordered QDs on facets and further to ordered QDson ridges occur. The predicted morphologies and their transitionsare in excellent agreement with existing experiments. Our study suggestsa novel approach to fabricate ordered nanostructures on nanowires. [ABSTRACT FROM AUTHOR]

We report on nanothin multilayer hydrogels of cross-linkedpoly(N-vinylcaprolactam) (PVCL) that exhibit distinctiveandreversible thermoresponsive behavior. The single-component PVCL hydrogelswere produced by selective cross-linking of PVCL in layer-by-layerfilms of PVCL-NH2copolymers assembled with poly(methacrylicacid) (PMAA) via hydrogen bonding. The degree of the PVCL hydrogelfilm shrinkage, defined as the ratio of wet thicknesses at 25 to 50°C, was demonstrated to be 1.9 ± 0.1 and 1.3 ± 0.1for the films made from PVCL-NH2-7 and PVCL-NH2-14 copolymers, respectively. No temperature-responsive behaviorwas observed for noncross-linked two-component films because of thepresence of PMAA. We also demonstrated that temperature-sensitivePVCL capsules of cubical and spherical shapes could be fabricatedas hollow hydrogel replicas of inorganic templates. The cubical (PVCL)7capsules retained their cubical shape when temperature waselevated from 25 to 50 °C exhibiting 21 ± 1% decrease inthe capsule size. Spherical hydrogel capsules demonstrated similarshrinkage of 23 ± 1%. The temperature-triggered capsule sizechanges were completely reversible. Our work opens new prospects fordeveloping biocompatible and nanothin hydrogel-based coatings andcontainers for temperate-regulating drug delivery, cellular uptake,sensing, and transport behavior in microfluidic devices. [ABSTRACT FROM AUTHOR]

The first phosphinobenzaldehyde- and phosphinoporphyrin-functionalizedmodel complexes (1–4) have been synthesizedand structurally characterized. Thus, reaction of diiron complex [(μ-SCH2)2CH2]Fe2(CO)6or [(μ-SCH2)2NC6H4CO2Me-p]Fe2(CO)6with p-Ph2PC6H4CHO in the presence of Me3NO gave the phosphinobenzaldehyde-functionalizedmodel complexes [(μ-SCH2)2CH2]Fe2(CO)5(p-Ph2PC6H4CHO) (1) and [(μ-SCH2)2NC6H4CO2Me-p]Fe2(CO)5(p-Ph2PC6H4CHO) (2) in 61% and71% yields, respectively. Further reaction of 1or 2with PhCHO, pyrrole, and BF3·OEt2followed by treatment with p-chloranil resultedin formation of the phosphinoporphyrin-functionalized model complexes5-{[(μ-SCH2)2CH2]Fe2(CO)5(p-Ph2PC6H4)}-10,15,20-triphenylporphyrin (3) and 5-{[(μ-SCH2)2NC6H4CO2Me-p]Fe2(CO)5(p-Ph2PC6H4)}-10,15,20-triphenylporphyrin(4) in 19% and 18% yields, respectively. While the newcomplexes 1–4were characterizedby elemental analysis and spectroscopy, the structures of 1, 3, and 4were confirmed by X-ray crystallography.Particularly interesting is that complex 4was foundto be a catalyst for the photoinduced H2production inthe presence of the electron donor EtSH and the proton source HOAc. [ABSTRACT FROM AUTHOR]

Pulmonary delivery of anticancer therapeutics has shown encouraging performance in treating nonsmall cell lung cancer (NSCLC), which is characterized by high aggressiveness and poor prognosis. Cisplatin, a key member of the family of DNA alkylating agents, is extensively employed during NSCLC therapy. However, the development of chemoresistance and the occurrence of side effects severely impede the long-term application of cisplatin-based chemotherapies. Herein, we propose a meaningful strategy to precisely treat cisplatin-resistant NSCLC based on the combination of bioorthogonal chemistry with an inhalation approach. Ethacraplatin (EA-Pt), a platinum prodrug (IV), was synthesized and encapsulated in nitric oxide (NO)-containing micelles to overcome cisplatin chemoresistance. By further modifying bioorthogonal molecules in this nanoplatform (EA-Pt@M DBCO ), an improved targeting performance toward pulmonary cancerous regions is achieved after prelabeling with azide via inhalation. Upon entering acidic cancer cells, EA-Pt is swiftly released due to the pH sensitivity of bioorthogonal micelles, which enables its bifunctions to inhibit glutathione S -transferase activity and deplete intracellular glutathione, eventually reversing cisplatin resistance. Moreover, the released NO also improves the overall therapeutic outcome against NSCLC. Consequently, inhalable EA-Pt@M DBCO prelabeled by azide effectively inhibits the progression of cisplatin-resistant orthotopic NSCLC, offering a feasible nanostrategy to expand the treatment options for NSCLC.

Polyvinylpolymethylsiloxane (PVPMS)/polydimethylsiloxane (PDMS) copolymer aerogels were synthesized via consecutive radical polymerization and cohydrolytic polycondensation of vinylmethyldimethoxysilane and dimethyldimethoxysilane, followed by supercritical drying or ambient pressure drying. The resultant PVPMS/PDMS copolymer aerogels exhibit a highly porous, tunable triple-network structure consisting of interlinked hydrocarbon polymers, PVPMS and PDMS. These aerogels display superhydrophobicity (151°), low density (109 mg cm -3 ), low thermal conductivity (29.8 mW m -1 K -1 ), and adjustable pore structure. The combination of good machinability, low thermal conductivity, excellent compressive elasticity and bending flexibility, and efficient organic solvent adsorption gives these aerogels broad application prospects in thermal insulation and oil-water separation. In addition, PVPMS/PDMS/carbon nanotube (CNT) composite aerogels were obtained by incorporating the conductive CNTs, followed by vacuum drying. The resultant PVPMS/PDMS/CNT composite aerogel exhibits high sensitivity with a broad pressure sensing range in strain and pressure sensing applications.

Light has profoundly impacted modern medicine and healthcare, with numerous luminescent agents and imaging techniques currently being used to assess health and treat diseases. As an emerging concept in luminescence, aggregation-induced emission (AIE) has shown great potential in biological applications due to its advantages in terms of brightness, biocompatibility, photostability, and positive correlation with concentration. This review provides a comprehensive summary of AIE luminogens applied in imaging of biological structure and dynamic physiological processes, disease diagnosis and treatment, and detection and monitoring of specific analytes, followed by representative works. Discussions on critical issues and perspectives on future directions are also included. This review aims to stimulate the interest of researchers from different fields, including chemistry, biology, materials science, medicine, etc., thus promoting the development of AIE in the fields of life and health.

Endocytosis, as one of the main ways for nanostructures enter cells, is affected by several aspects, and shape is an especially critical aspect during the endocytosis of nanostructures. However, it has remained challenging to capture the dynamic internalization behaviors of rod-shaped nanostructures while also probing the mechanical aspects of the internalization. Here, using the atomic force microscopy-based force tracing technique, transmission electron microscopy, and molecular dynamic simulation, we mapped the detailed internalization behaviors of rod-shaped nanostructures with different aspect ratios at the single-particle level. We found that the gold nanorod is endocytosed in a noncontinuous and force-rebound rotation manner, herein named "intermittent rotation". The force tracing test indicated that the internalization force (∼81 pN, ∼108 pN, and ∼157 pN) and time (∼0.56 s, ∼0.66 s, and ∼1.14 s for a 12.10 nm × 11.96 nm gold nanosphere and 26.15 nm × 13.05 nm and 48.71 nm × 12.45 nm gold nanorods, respectively) are positively correlated with the aspect ratios. However, internalization speed is negatively correlated with internalization time, irrespective of the aspect ratio. Further, the energy analysis suggested that intermittent rotation from the horizontal to vertical direction can reduce energy dissipation during the internalization process. Thus, to overcome the energy barrier of internalization, the number and angle of rotation increases with aspect ratios. Our findings provide critical missing evidence of rod-shaped nanostructure's internalization, which is essential for fundamentally understanding the internalization mechanism in living cells.

Because of the deficiency of lymphatic reflux in the tumor, the retention of tumor interstitial fluid causes aggravation of the tumor interstitial pressure (TIP), which leads to unsatisfactory tumor penetration of nanomedicine. It is the main inducement of tumor recurrence and metastasis. Herein, we design a pyroelectric catalysis-based "Nano-lymphatic" to decrease the TIP for enhanced tumor penetration and treatments. It realizes photothermal therapy and decomposition of tumor interstitial fluid under NIR-II laser irradiation after reaching the tumor, which reduces the TIP for enhanced tumor penetration. Simultaneously, reactive oxygen species generated during the pyroelectric catalysis can further damage deep tumor stem cells. The results indicate that the "Nano-lymphatic" relieves 52% of TIP, leading to enhanced tumor penetration, which effectively inhibits the tumor proliferation (93.75%) and recurrence. Our finding presents a rational strategy to reduce TIP by pyroelectric catalysis for enhanced tumor penetration and improved treatments, which is of great significance for drug delivery.