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The core factors affecting the efficiency of photocatalysis are predominantly centered on controllable modulation of anisotropic spatial charge separation/transfer and regulating vectorial charge transport pathways in photoredox catalysis, yet it still meets with limited success. Herein, we first conceptually demonstrate the rational design of unidirectional cascade charge transfer channels over transition metal chalcogenide nanosheets (TMC NSs: ZnIn2S4, CdS, CdIn2S4, and In2S3), which is synergistically enabled by a solid-state non-conjugated polymer, i.e., poly(diallyldimethyl ammonium chloride) (PDDA), and MXene quantum dots (MQDs). In such elaborately designed photosystems, an ultrathin PDDA layer functions as an intermediate charge transport mediator to relay the directional electron transfer from TMC NSs to MQDs that serve as the ultimate electron traps, resulting in a considerably boosted charge separation/migration efficiency. The suitable energy level alignment between TMC NSs and MQDs, concurrent electron-withdrawing capabilities of the ultrathin PDDA interim layer and MQDs, and the charge transport cascade endow the self-assembled TMC/PDDA/MQD heterostructured photosystems with conspicuously improved photoactivities toward anaerobic selective reduction of nitroaromatics to amino derivatives and photocatalytic hydrogen evolution under visible light irradiation. Furthermore, we ascertain that this concept of constructing a charge transfer cascade in such TMC-insulating polymer-MQD photosystems is universal. Our work would afford novel insights into smart design of spatial vectorial charge transport pathways by precise interface modulation via non-conjugated polymers for solar energy conversion., Electron relay of interim polymer layer boosts photocatalytic organic transformation.

Transition metal chalcogenides quantum dots (TMCs QDs) demonstrate emerging potential in solar energy conversion owing to marvelous physicochemical properties, such as quantum size effect, large extinction coefficient, and multiple excitons generation. Nevertheless, TMCs QDs as photosensitizers are unstable owing to high surface energy, and moreover, substantial trap states of TMCs QDs annihilate the photo-induced charge carriers, thus resulting in ultra-short charge lifetime and inferior photoactivities. Herein, 0D/2D TMCs QDs/MXene heterostructures were designed by a ligand-initiated electrostatic self-assembly strategy, wherein positively charged TMCs QDs were anchored on the negatively charged ultrathin Ti 3C2Tx nanosheets (NSs) framework, which promotes the anisotropic unidirectional electron transport from TMCs QDs to MXene NSs. MXene functions as an effective charge mediator to decrease the charge recombination and prolong the charge lifetime for photocatalytic hydrogen generation and anaerobic reduction of nitroaromatics to amino compounds under visible light irradiation. Our work would shed new insights on the role of MXene in tuning the directional charge transport for solar energy conversion.

Oxaliplatin (OXA) is a third-generation, platinum-based anticancer agent that is reported to induce cell toxicity in normal cells, which severely limits its applications. Its instability in aqua so...

Ionic liquids (IL) technology provides a useful platform to achieve the topical delivery of therapeutic agents, because of its capability to improve skin permeability. While the majority of the researches aimed to achieve local action by topical IL delivery, systemic action of therapeutic agents by local topical application has rarely been reported. In the present work, Gliclazide (GLI), a second-generation sulfonylurea drug was transformed into an IL with tributyl(tetradecyl)phosphonium for the first time. The physicochemical properties of this IL were systematically characterized by DSC, TGA, FT-IR, NMR, and HPLC. The transdermal patch based on this IL was further prepared using DURO-TAK®87-4098. The fabricated gliclazide based ionic liquid [P6,6,6,14][GLI] transdermal patch displayed satisfactory in vitro and in vivo performance. The [P6,6,6,14][GLI] patch released 88.17% of the loaded drug within a 3-day period in the in vitro dissolution test, confirming its sustained release property. Meanwhile, GLI effectively permeated through the artificial skin from [P6,6,6,14][GLI] transdermal patch in the in vitro skin permeation test, with the permeation rate and lag time of 16.571 ± 0.328 μg/cm2/h and 3.027 ± 0.154 h respectively. The [P6,6,6,14][GLI] transdermal patch showed favorable PK profile in rat as compared with GLI oral suspension. The relative bioavailability of GLI reached 92.06% of GLI oral suspension, while the Cmax was significantly reduced. Most importantly, [P6,6,6,14][GLI] transdermal patch demonstrated superior hypoglycemic effect to the oral suspension both in the fasted and fed condition, confirming the feasibility of systemic action by local topical delivery of IL. In addition, the [P6,6,6,14][GLI] transdermal patch caused no skin irritation based on histopathological analysis.

A nitrogen/sulfur-doped porous carbon material (NSPC) was synthesized using petroleum asphalt as both carbon and sulfur sources, and graphitic carbon nitride (g-C3N4) as a template and nitrogen source. Its use as the counter electrode (CE) of dye-sensitized solar cells (DSSCs) was investigated. Results indicated that g-C3N4 was totally decomposed during carbonization, giving the NSPC abundant N dopants and nanopores. The NSPC had a high electrocatalytic activity for the reduction of I3- without any Pt catalyst and delivered a high power conversion efficiency of 7.91% as the CE of a DSSC, which is slightly superior to that of Pt CE. The NSPC had an ultrahigh pore volume (4.49 cm3/g) and excellent wettability, providing abundant accessible surface area and facilitated the fast mass transport of reactants. NSPC has potential as a low-cost and efficient CE material for the large-scale use of DSSCs, and provides a new way to add value to low-cost petroleum asphalt.

Photocyanine, a novel amphoteric phthalocyanine drug, showed favorable anticancer activity in vivo. Pharmacokinetic study in cancer patients is an important component in dose administration choice. In this study, a rapid, sensitive analytical method based on high-performance liquid chromatography with ultraviolet detection was developed and validated for the determination of four isomers of photocyanine (FD1-4) in cancer patients. Sample preparation involved liquid-liquid extraction with a combination of ultrasound and N,N-dimethyl formamide. Calibration curves (1/x(2)) offered satisfactory linearity for the four isomers of photocyanine. The lower limit of quantification (LLOQ) for FD1-3 isomers was 30 ng/mL, and LLOQ for FD-4 was 5 ng/mL. Inter- and intra-day accuracies for four isomers ranged from 96.6 to 105.5%, and 95.0 to 103.6%, respectively. Inter- and intra-day precision ranged from 4.8 to 8.9%, and 3.6 to 12.2%, respectively. Stability studies showed that photocyanine was stable. This method was successfully used to quantify photocyanine in a pharmacokinetic study in which a single-dose of photocyanine (0.1 mg/kg) was intravenously administered to patients with cancer. On the basis of the discovery that photocyanine has a half-life of 57.5 h in vivo, we suggest that avoiding light for a longer period is essential for patients undergoing photocyanine therapy.

Currently, the most widely used photoresists in optical lithography are organic-based resists. The major limitations of such resists include the photon accumulation severely affects the quality of photolithography patterns and the size of the pattern is constrained by the diffraction limit. Phase-change lithography, which uses semiconductor-based resists such as chalcogenide Ge2Sb2Te5 films, was developed to overcome these limitations. Here, instead of chalcogenide, we propose a metallic resist composed of Mg58Cu29Y13 alloy films, which exhibits a considerable difference in etching rate between amorphous and crystalline states. Furthermore, the heat distribution in Mg58Cu29Y13 thin film is better and can be more easily controlled than that in Ge2Sb2Te5 during exposure. We succeeded in fabricating both continuous and discrete patterns on Mg58Cu29Y13 thin films via laser irradiation and wet etching. Our results demonstrate that a metallic resist of Mg58Cu29Y13 is suitable for phase change lithography, and this type of resist has potential due to its outstanding characteristics.

The title compound, C9H10N4S, has been used as an inter­mediate in the synthesis of potassium channel openers, which show considerable biomolecular current-voltage rectification characteristics. In this crystal form, attractive C—H⋯N hydrogen bonds between neighboring mol­ecules form a centrosymmetric ten-membered ring. In addition, inter­molecular N—H⋯N hydrogen bonds form zigzag mol­ecular chains propagating in the b-axis direction.

The title compound, C12H20N4O2S, has been synthesized for use as an inter­mediate for antihypertensive agents, potential antimalarials and mol­ecular rectification materials. The inter­molecular S⋯N non-bonded separation within a column in the crystal structure is 3.308 (2) A, indicating a strong inter­molecular inter­action between the cyano groups and the S atoms. Attractive C—H⋯O hydrogen bonds are responsible for zigzag mol­ecular chains propagating in the a-axis direction; these types of inter­molecular inter­actions combine to form an extended three-dimensional network in the lattice.

The title compound, C17H21N3, is a chemically symmetric mol­ecule with one methyl group and three (pyrrol-1-yl)­methyl groups bonded to a central C atom. It crystallizes in the non-centrosymmetric space group P212121. The three (pyrrol-1-yl)­methyl groups are orientated differently with respect to one another and to the central C—CH3 bond; hence, the mol­ecule exhibits conformational chirality. The crystal structure is homochiral and contains just one type of enantiomer. In the crystal structure, a herring-bone packing of the supramolecular assemblies is revealed.

The title compound, C45H60N8, is a symmetric mol­ecule with four chemically identical substituents bonded to a central C atom. In the crystal structure, the 4-phenyl­piperazin-1-yl groups exhibit four different conformations, with no obvious pseudosymmetry.

Maskless phase-change lithographic technology is developed as a photoresist of phase-change materials. The controllable growth behavior of the crystallization region on an amorphous thin film of Ge 2 Sb 2 Te 5 (GST) irradiated by a laser beam is investigated; the GST thin film is deposited on a silicon substrate by the sputtering method. The results of a series of the experiments and the simulations all show that the width of a crystalline pattern is not only closely related to laser power and pulse duration, but also is apparently affected by the interactive area between the focused laser spot and thin film. The width maintains a nonlinear growth with the enhancement of the laser power until the thin film approaches melting, whereas it gradually reaches a constant value due to the local thermal equilibrium. This equilibrium makes the width irrelevant to the moving velocity with certain constraints when the laser works in continuous-wave mode. Within a defocus range of 15 μ m , the widths of the crystalline patterns are obtained in a broad range from 690 nm to 8.13 μ m under a 0.4-NA objective lens. By adjusting the defocus amount, some crystalline square patterns with expected widths in a wide range are fabricated, and the mean percentage error between the expected and fabricated widths is only 1.495%.