Oxidative Upcycling of Polyethylene to Long Chain Diacid over Co-MCM-41 Catalyst.

Plastic pollution is an emerging global threat due to lack of effective methods for transforming waste plastics into useful resources. Here, we demonstrate a direct oxidative upcycling of polyethylene into high-value and high-volume saturated dicarboxylic acids in high carbon yield of 85.9 % in which the carbon yield of long chain dicarboxylic (C10-C20) acids can reach 58.

Rapid chiral assay of amino compounds using diethyl squarate.

The versatility and importance of chiral compounds make it urgent to develop fast and efficient methods to detect the absolute configuration, enantiomeric excess(ee), and concentration of chiral compounds. In this study, we demonstrate that commercially available diethyl squarate can rapidly react with various types of chiral amino compounds and exhibit characteristic ultraviolet (UV) and circular dichroism (CD) signals. The UV and CD signals can determine the total concentration of the two enantiomers and ee value of the sample, respectively.

Catalytic asymmetric multicomponent reactions of isocyanide, isothiocyanate and alkylidene malonates.

Several unique chiral 3,4-dihydro-2H-pyrrole-2-thiones were made readily available by carrying out, in each case, a chiral-Mg(OTf)/N,N'-dioxide-complex-promoted formal [2+1+2] cycloaddition in the presence of tetraethylenediamine. Control experiments revealed that in situ-generated ammonium thiocyanate was crucial for maintaining high enantioselectivity through its inhibition of the HNCS-induced racemization of the products.

Hierarchical Targeted Delivery of Lonidamine and Camptothecin Based on the Ultra-Rapid pH/GSH Response Nanoparticles for Synergistic Chemotherapy.

A facile strategy to construct dual-drug delivery nanoparticles (), which possessed higher loading content of CPT and TPP-LND. Notably, showed promising ultrarapid pH/GSH response to release more than 86% of loaded TPP-LND or 93% of loaded CPT in just 2 h. The results showed that the nanoparticles hierarchically delivered CPT and TPP-LND to targeted different organelles without mutual influence benefiting the ultrarapid pH/GSH response to drug release, and further significantly and synergistically induced cell apoptosis and improved chemotherapeutic efficiency in cancer cells.

A novel near-infrared fluorescent sensor for zero background nitrite detection via the "covalent-assembly" principle.

Different chemical states of nitrogen are present in many freshwater and marine ecosystems, and nitrite ions are one of the most toxic water-soluble nitrogen species. Developing an effective and convenient sensing method to constantly detect the concentration of nitrite has become a wide concern. Here, a novel near-infrared fluorescent probe (AAC) was designed and synthesized via the "covalent assembly" principle, showing excellent selectivity and high sensitivity for nitrite.

Enantioselective dicarbofunctionalization of ()-alkenyloxindoles with pyridinium salts by chiral Lewis acid/photo relay catalysis.

A highly efficient enantioselective dicarbofunctionalization reaction of (E)-alkenyloxindoles with pyridinium salts was realized. The process includes the chiral N,N'-dioxide-Sc(iii) complex-catalyzed regio-, diastereo-, and enantioselective [3+2] cycloaddition reaction and the following photo-promoted aza-Norrish II type rearrangement. A series of 2-pyridyl substituted oxindole derivatives were obtained in good yields with moderate to good diastereo- and enantioselectivities.

Trackable Water-Soluble Prodrug Micelles Capable of Rapid Mitochondrial-Targeting and Alkaline pH-Responsive Drug Release for Highly Improved Anticancer Efficacy.

A trackable water-soluble prodrug conjugate possessing high contents of chlorambucil () and triphenylphosphonium cation () was designed and developed after TPP modification on the "branch" of amphipathic prodrugs based on convenient synthesis of heterobifunctional clickable poly(ethylene glycol) (). The aqueous self-assembly of fluorescent polymeric micelles along precise composition can be easily prepared after directly dissolved () in aqueous solution, and exhibit superior cytotoxicity to cancer cells along with highly improved selectivity and sensitivity because of their rapid mitochondrial-targeting and alkaline pH-responsive drug release capabilities. Notably, efficient codelivery of doxorubicin () for synergistic targeted drug delivery and cancer therapy was achieved.

Electrocatalytic Hydrogenation of N to NH by MnO: Experimental and Theoretical Investigations.

NH is a valuable chemical with a wide range of applications, but the conventional Haber-Bosch process for industrial-scale NH production is highly energy-intensive with serious greenhouse gas emission. Electrochemical reduction offers an environmentally benign and sustainable route to convert N to NH at ambient conditions, but its efficiency depends greatly on identifying earth-abundant catalysts with high activity for the N reduction reaction. Here, it is reported that MnO particles act as a highly active catalyst for electrocatalytic hydrogenation of N to NH with excellent selectivity.

Fluorescent Zn Chemosensor Mediated by a 1,8-Naphthyridine Derivative and It's Photophysical Properties.

One of the greatest challenges in using fluorescent chemosensors for highly selective and sensitive transition-metal ions is finding an efficient and simple method for its synthesis. In this study, a highly efficient fluorescence chemosensor for Zn was developed from -Boc-proline modified 1,8-naphthyridine. The fluorescence intensity of the chemosensor was increased significantly only in the presence of Zn ion which provided a perceived color change for rapid visual sensing, while other metal ions showed fluorescence quenching or little changes.

A reaction-based ratiometric fluorescent sensor for the detection of Hg(ii) ions in both cells and bacteria.

A novel reaction-based fluorescent probe (ATC-Hg) was designed and synthesized via the "covalent assembly" principle, which exhibited excellent selectivity and high sensitivity for Hg2+ and CH3Hg+. Moreover, it is the first Hg(ii) sensitive fluorescent probe that has been successfully applied in imaging in both cells and Escherichia coli.

A tumor-specific and mitochondria-targeted fluorescent probe for real-time sensing of hypochlorite in living cells.

A biotin-rhodamine-TPP conjugate (BiTClO) was reported as a real-time (within 10 s) fluorescent probe for the sensing of mitochondrial hypochlorite with excellent selectivity and high sensitivity (0.21 μM). Moreover, it is the first tumor-specific and mitochondria-targeted fluorescent probe applied in cell imaging.

Novel mitochondria-targeted, nitrogen mustard-based DNA alkylation agents with near infrared fluorescence emission.

In this report, the design of two novel nitrogen mustard-based DNA cross-linking agents with fluorophores incorporated into the structure (TN-A and TN-B) is disclosed. The results indicate that TN-A and TN-B can serve directly as both reporting and imaging agents for flow cytometry and gel electrophoresis without the necessity of another fluorescent tagging agents. TN-A and TN-B both selectively locate in the mitochondria and exhibit good antitumor activity.

A mitochondria-targeted colorimetric and ratiometric fluorescent probe for biological SO2 derivatives in living cells.

A ratiometric fluorescent probe for SO2 derivatives based on the conjugate of carbazole and indolium was presented, which could selectively respond to HSO3(-) over other thiol compounds. More importantly, CZ-Id is a novel mitochondria-targeted ratiometric fluorescent probe to image exogenous SO2 derivatives.

A ratiometric fluorescent probe for in situ quantification of basal mitochondrial hypochlorite in cancer cells.

A ratiometric fluorescent probe () for ClO(-) based on the conjugate of coumarin-rhodamine was presented, which could sense ClO(-) with fast response (within 5 s), high sensitivity and excellent selectivity. More importantly, is the first mitochondria-targeted ratiometric fluorescent probe to image exogenous and endogenous ClO(-).

Purification and separation of single-walled carbon nanotubes (SWCNTs).

Purification or separation of single-walled carbon nanotubes (SWCNTs) is one of the most fundamental steps before they are used for research and technological applications. Based on the difference of their physical and chemical properties, separation of carbon nanotubes (CNTs) can be categorized into three groups: length separation, metallic and semiconducting tubes separation and chirality separation. In this review, we first briefly review the purification of CNTs and then focus on the different methods for the separation of CNTs.