Latest ArticlesThe effect of gold nanoparticle-decorated molybdenum sulfide (AuNP-MoS2) nanocomposites on amyloid-β-40 (Aβ40) aggregation was investigated. The interesting discovery was that the effect of AuNP-MoS2 nanocomposites on Aβ40 aggregation was contradictory. Low concentration of AuNP-MoS2 nanocomposites could enhance the nucleus formation of Aβ40 peptides and accelerate Aβ40 fibrils aggregation. However, although high concentration of AuNP-MoS2 nanocomposites could enhance the nucleus formation of Aβ40 peptides, it eventually inhibited Aβ40 aggregation process. It might be attributed to the interaction between AuNP-MoS2 nanocomposites and Aβ40 peptides. For low concentration of AuNP-MoS2 nanocomposites, it was acted as nuclei, resulting in the acceleration of the nucleation process. However, the structural flexibility of Aβ40 peptides was limited as the concentration of AuNP-MoS2 nanocomposites was increased, resulting in the inhibition of Aβ40 aggregation. These findings suggested that AuNP-MoS2 nanocomposites might have a great potential to design new multifunctional material for future treatment of amyloid-related diseases.
The recent development of selective oxidation of aromatic sulfides with molecular oxygen was highlighted. The sulfoxides and sulfones could be obtained by simply switching the reaction media, i.e., bis(2-butoxyethyl)ether (BBE) or poly(ethylene glycol)dimethyl ether (PEGDME). The application of the high-boiling-point polyether as an initiator and green media can eliminate the need of large quantities of additives and volatile solvents. This strategy represents an economic and eco-friendly method that could find potential applications.
Chemodynamic therapy (CDT) refers to generating hydroxyl radical (·OH) in tumor sites via hydrogen peroxide (H2O2) catalyzed by transition metal ions in cancer cells under acidic environment. However, H2O2 content is not enough for effective CDT, although H2O2 content in cancer cells is higher than that of normal cells. Herein, we synthesized DOX@BSA-Cu NPs (nanoparticles) for effective CDT by providing enhanced content of H2O2 in cancer cells. The results proved Cu2+ in NPs could be reduced to Cu+ by glutathione (GSH) and effectively converted H2O2 to ·OH. Moreover, the loaded low-dose doxorubicin (DOX) in the NPs could improve the content of H2O2 and resulted in more efficient generation of ·OH in cancer cells. Thus DOX@BSA-Cu NPs exhibited higher cytotoxicity to cancer cells. This research may provide new ideas for the further studies on more effective Cu(II)-based CDT nanoagents.
The recent molecular iodine catalyzed [1, 2]-rearrangement of aryl amines and 3-amino-1H-indazolesfor the synthesis of 1, 2, 3-benzotriazines is highlighted.
Niobium carbide MXene quantum dots (Nb2C MQDs) derived from 2D Nb2CTx (MXene) are the rising-star material recently. Herein, a sulfur and nitrogen co-doped Nb2C MQDs (S, N-MQDs) were synthesized through a hydrothermal method. The obtained Nb2C MQDs have excellent green fluorescence with a quantum yield (QY) of 17.25%. In addition, they exhibited excitation-dependent photoluminescence, anti-photobleaching and dispersion stability. They emit light at 520 nm when excited at 390 nm. The Nb2C MQDs could be successfully applied to copper ion detection with detection limit of 2 μmol/L and Caco-2 cells imaging.
A hybrid system containing a pillar[5]arene unit and ten crown ether moieties was developed. The LCST behavior and thermo-responsiveness were successfully introduced into this pillar[5]arene-crown ether system. Both host-guest interactions and salting-out effect displayed great effects in realizing the supramolecular control over LCST properties and thermo-responsiveness. Compared with the individual macrocycles, this hybrid macrocycle system dramatically amplified the supramolecular control effect over LCST behavior.
Fragrances are widely used in many aspects of our lives. They cannot only make people happy, but also treat many diseases. However, excessively fast evaporation rate is one of the main obstacles to the use of spices. In this study, mesoporous silica nanorods (MSNRs) and hollow mesoporous silica nanorods (HMSNRs) were prepared to encapsulate eugenol. These two nano-fragrances were named eugenol@MSNRs and eugenol@HMSNRs, respectively. The morphologies, size, interior structures and pore performances of MSNRs and HMSNRs. Besides, the performances of encapsulation and fragrance release of eugenol@MSNRs and eugenol@HMSNRs were compared and analyzed. The results showed that eugenol@HMSNRs encapsulated more fragrance and were faster to encapsulate compared with eugenol@MSNRs. Both the release rates of eugenol from eugenol@MSNRs and eugenol@HMSNRs were slow. But the eugenol was released from eugenol@MSNRs more slowly.
Surface modification by poly(ethylene glycol) (PEGylation) has been acknowledged as a powerful strategy in minimizing non-specific reactions for biomedical devices. Once applied into manufacture of drug/gene delivery systems, PEGylation has demonstrated to significantly improve their biocompatibility and stealthiness in physiological environment. Nonetheless, reluctant cell membrane affinities thus cellular uptake efficiencies owing to PEGylation brought up further issues that are imperative to be resolved. Pertain to this PEGylation dilemma, we attempted to introduce peptide (GPLGVRG) linkage between block copolymer of PEG-poly{N'-[N-(2-aminoethyl)-2-aminoethyl]aspartamide} PAsp(DET), wherein the cationic PAsp(DET) could self-assemble with pDNA into nanoscaled complex core. Noteworthy was the peptide linkage whose amino acids sequence could be specifically recognized and degraded by matrix metalloproteinases (MMPs) (overexpressed in extracellular milieu of tumors). Therefore, our subsequent studies validated facile detachment of PEGylation from the aforementioned polyplex micelles upon treatment of MMPs, which elicited improved cytomembrane affinities and cellular uptake efficiencies. In addition, promoted escape from endosome entrapment was also confirmed through direct endosome membrane destabilization by PAsp(DET), which was further elucidated to be attributable to dePEGylation as well as elevated charged density of PAsp(DET) in acidic endosomes. These benefits from dePEGylation eventually contributed to promoted gene expression at the affected cells and potent tumor growth suppression based on anti-angiogenic approach. Therefore, our developed strategy has provided a facile approach in overcoming the dilemma of PEGylation, which could be informative in design of drug/gene delivery systems.
Constructing a reliable and favorable electrode-electrolyte interface is crucial to utilize the exceptional energy storage capability in commercial lithium-ion batteries. Here, we report a facile synthesis approach for the lithium difluorophosphate (LiPO2F2) solution as an effective film-forming additive via direct adding the Li2CO3 into LiPF6 solution at 45 ℃. Benefiting from the significantly reduced interface resistance (RSEI) and charge transfer impedance (Rct) of both the cathode and anode by adding the prepared LiPO2F2 solution into a baseline electrolyte, the cycling performance of the graphite‖LiNi0.5Mn0.3Co0.2O2 pouch cell is remarkably improved under all-climate condition.
The two-dimensional surfaces have been fueled by the infinite possibility they offered for basic research, and for novel technologies in nanoelectronics. To realize many of these promises, the effective strategies were to design and control their surface chemistry, which plays a vital role in determining the chemical and physical properties. Macrocyclic host-guest chemistry with the reversible noncovalent interactions between macrocyclic hosts and suitable guests can be readily used for constructing multifunctional surfaces. Macrocyclic pillararenes, possessed the unique structure, have attracted the attentions of researchers in recent years. This feature article covers the recent development of pillararene-based two-dimensional interfaces, including the fabrication and function of the hybrid composite. The combination of pillararenes and materials platform exhibited the novel property because of the characteristic of cavity of macrocyclic host and confined spaces of surfaces. We anticipate that this review will be helpful to the researchers working in the fields of supramolecular chemistry and materials science.