Self-healing gels triggered by ultrasound with color-tunable emission based on ion recognition.

Herein, O-substituted terpyridine motif was used as both rigid fluorescent π core and ion binding site, in order to construct an novel amphiphilic organogelator TEC containing cholesterol unit. We demonstrated a ultrasound induced reversible sol-gel transition approach driven by adjusted non covalent interactions and the resulted gels showed self-healing properties and tunable emission color when incorporating inorganic ions into the gel matrices. By heating-cooling process, the gel transformed to sol again.

Novel luminescent lanthanide(iii) hybrid materials: fluorescence sensing of fluoride ions and N,N-dimethylformamide.

Two novel luminescent organic-inorganic hybrid materials, Ln(L-SBA15)3phen (Ln = Eu, Tb), were designed and synthesized. The organic ligand phenylurea was modified by the silane coupling agent 3-(triethoxysilyl)propyl isocyanate (TESPIC) to form a precursor (L), which was covalently bonded onto a mesoporous SBA-15 backbone to form mesoporous L-SBA15 through co-hydrolysis and co-condensation reactions. 1,10-Phenanthroline monohydrate (phen) was selected as the second ligand to improve the luminescence of the final products, and the two mesoporous hybrid materials Ln(L-SBA15)3phen were obtained after the coordination reaction between the organic ligands (phen and L-SBA15) and Ln(iii) ions.

The differences between GluN2A and GluN2B signaling in the brain.

The N-methyl-d-aspartate (NMDA) receptor, a typical ionotropic glutamate receptor, is a crucial protein for maintaining brain function. GluN2A and GluN2B are the main types of NMDA receptor subunit in the adult forebrain. Studies have demonstrated that they play different roles in a number of pathophysiological processes.

Facile construction of terpridine-based metallo-polymers in hydrogels, crystals and solutions directed by metal ions.

Driven by tunable metal-ligand interactions, a polydentate ligand TC containing terpyridine and carboxylic acid units was developed to construct metallo-polymers that showed multiple aggregation modes with controlled macroscopic properties. In the presence of different kind of Zn ions or NaOH, TC could form metallo-polymers via π-π stacking and metal-ligand interaction that further trapped water molecules, resulting in hydrogels and crystals. Moreover, these TC/Zn hydrogels could transform to soluble and fluorescent aggregates in the presence of NaOH due to the formation of binuclear metallo-polymers with enhanced ICT emission.

Synthesis, characterization and in vitro release performance of the pegylated valnemulin prodrug.

Valnemulin, successfully developed by Sandoz in 1984, is a new generation derivative of pleuromutilin related to tiamulin. Valnemulin has low water-solubility, a short half-life period, low bioavailability, and instability. The application of valnemulin was restricted.

Relationship between the color stability and impurity profile of cefotaxime sodium.

The color grade, mainly introduced in the processes of semisynthesis and storage, is an important index used to evaluate the quality of cefotaxime sodium. Because the drug itself is prone to degradation under susceptible conditions, including those involving moisture, heat, ultraviolet light, acids, alkalis, and oxidants, and a series of degradation products as impurities are generated. In this study, the factors affecting color grade stability and the degradation mechanisms of cefotaxime sodium were investigated by designing different accelerated stability tests under the aforementioned conditions.

Robust, Self-Healing, and Multistimuli-Responsive Supergelator for the Visual Recognition and Separation of Short-Chain Cycloalkanes and Alkanes.

In this study, we show that a novel kind of cholesterol-based gelator NPS containing pyridyl and naphthalimide units can visually discriminate cyclohexane/cyclopentane from hexane/pentane on the basis of distinct optical differences in the gel platform, which is not observed in solution. The effect of congeneric solvents on the gel properties, such as morphology, rheology, and stimuli-responsive properties, is also studied. Intriguingly, NPS can form self-supporting, self-healing, fluorescent, and highly visible transmittance gels in cyclohexane that can selectively and visually respond to picric acid.

The Role of GluN2A in Cerebral Ischemia: Promoting Neuron Death and Survival in the Early Stage and Thereafter.

Over-activation of NMDA receptors is a crucial step required for brain damage following a stroke. Although clinical trials for NMDA receptor blockers have failed, the role of GluN2A subunit in cerebral ischemia has been extensively evaluated in recent years. However, the effect of GluN2A on neuron damage induced by cerebral ischemia remains a matter of controversy.

Cyclodextrin-Assisted Two-Component Sonogel for Visual Humidity Sensing.

In this work, two naphthalimide-based compounds, 1a and 1b, have been designed and synthesized. Both compounds can form stable two-component gels in n-propanol or n-butanol upon addition of α-cyclodextrin (α-CD) followed by sonication at room temperature. Interestingly, the 1a/α-CD gel is thixotropic and very sensitive to water.

Tunable multicolor emissions in a monocomponent gel system by varying the solvent, temperature and fluoride anion.

The facile tuning of the fluorescent properties of organogels is highly desirable for optical switches, light-emitting diodes, chemosensors and bioprobes. The design of organic molecules with multiple emission colors but only one molecular platform remains challenging. Herein, a new cholesterol-based organogelator N1 containing D-A pairs (salicylaldehyde and naphthalimide units) was designed.

The Regulation of GluN2A by Endogenous and Exogenous Regulators in the Central Nervous System.

The NMDA receptor is the most widely studied ionotropic glutamate receptor, and it is central to many physiological and pathophysiological processes in the central nervous system. GluN2A is one of the two main types of GluN2 NMDA receptor subunits in the forebrain. The proper activity of GluN2A is important to brain function, as the abnormal regulation of GluN2A may induce some neuropsychiatric disorders.

Determination of six polyether antibiotic residues in foods of animal origin by solid phase extraction combined with liquid chromatography-tandem mass spectrometry.

A new method using solid phase extraction (SPE) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been developed for the determination of six polyether antibiotics, including lasalocid, salinomycin, monensin, narasin, madubamycin and nigericin residues, in foods of animal origin. The samples were extracted with acetonitrile and purified by ENVI-Carb SPE columns after comparing the impurity effect and maneuverability of several SPE cartridges. Subsequently, the analytes were separated on a Hypersil Gold column (2.

The Functional and Molecular Properties, Physiological Functions, and Pathophysiological Roles of GluN2A in the Central Nervous System.

The NMDA receptor, which is heavily involved in several human brain diseases, is a heteromeric ligand-gated ion channel that interacts with multiple intracellular proteins through the C-termini of different subunits. GluN2A and GluN2B are the two primary types of GluN2 subunits in the forebrain. During the developmental period, there is a switch from GluN2B- to GluN2A-containing NMDA receptors in synapses.

Ultrasound-accelerated organogel: application for visual discrimination of Hg(2+) from Ag(+).

A new kind of naphthalimide-based organogelator, TN, was designed and synthesized. The intramolecular guanylation of TN promoted by Hg(2+) or Ag(+) in both solution and gel state was studied through several approaches including FL, UV-visible, NMR, FT-IR and SEM experiments. TN could selectively sense Hg(2+) and Ag(+) ions with obvious fluorescence quenching and color changes from yellow to colorless among test ions in the solution state.

Tunable and Switchable Control of Luminescence through Multiple Physical Stimulations in Aggregation-Based Monocomponent Systems.

This report describes how the luminescence of naphthalimide could be tuned by various physical stimuli, including heat, sonication, and grinding. Herein, instant and switchable control of color and fluorescent emissions has been achieved by the sonication-triggered gelation of an organic liquid with naphthalimide-based organogelators (N3-N7). Green emissive suspensions of the gelators in organic liquids are transformed into orange emissive gels upon brief irradiation with ultrasound with an emission wavelength red-shift of approximately 60 nm and fluorescence intensity quenching by a factor of 20, which can subsequently be reversed by heating.

Selective and visual Ca(2+) ion recognition in solution and in a self-assembly organogel of the terpyridine-based derivative triggered by ultrasound.

A new kind of terpyridine-based Ca(2+) sensor TS was designed and studied based on the internal charge transfer (ICT). In the diluted solution state, TS sensed Ca(2+) and Mg(2+) ions among test ions via an "off-on" approach as seen from fluorescence spectra of test ions. Moreover, TS was able to form stable fluorescent gels in organic solvents accelerated by ultrasound, indicating the ultrasound responsive properties of TS molecules.

Visual Recognition of Aliphatic and Aromatic Amines Using a Fluorescent Gel: Application of a Sonication-Triggered Organogel.

A naphthalimide-based fluorescent gelator (N1) containing an alkenyl group has been designed and characterized. This material is able to gelate alcohols via a precipitate-to-gel transformation when triggered with ultrasound for less than 2 min (S-gel). The gelation process in n-propanol was studied by means of absorption, fluorescence, and IR spectra, scanning electron microscopy (SEM) images, and X-ray diffraction patterns.

Improved propionic acid and 5,6-dimethylbenzimidazole control strategy for vitamin B12 fermentation by Propionibacterium freudenreichii.

An efficient fermentation-strengthening approach was developed to improve the anaerobic production of vitamin B12 by cultivation process optimization with Propionibacterium freudenreichii. The effects of the byproduct propionic acid and the precursor 5,6-dimethylbenzimidazole (DMB) on vitamin B12 biosynthesis were investigated. Byproduct inhibition experiments showed that maintaining propionic acid concentration in broth below 10-20 g/L in the early stage and 20-30 g/L in the late stage can efficiently improve vitamin B12 biosynthesis.

Intramolecular proton transfer through the adjoining π-conjugated system in Shiff base: application for colorimetric sensing of fluoride anion.

In this paper, a new kind of phenol-based chemsensor L2 comprised of a Schiff base and azo groups was rationally designed and synthesized. It could selectively recognize fluoride anion among tested anions such as F(-), AcO(-), H2PO4(-), Cl(-), Br(-), and I(-) with obvious color changes from yellow to fuchsia. The intramolecular PT (proton transfer) in L1 and L2 was responsible for the sensing ability, which was certified by the (1)H NMR and Uv-vis experiments.

Methyl 2-[2-(benzyl-oxycarbon-ylamino)-propan-2-yl]-5-hy-droxy-1-methyl-6-oxo-1,6-dihydro-pyrimidine-4-carboxyl-ate.

The title pyrimidine derivative, C(18)H(21)N(3)O(6), was obtained by the reaction of methyl 2-[2-(benzyl-oxycarbon-yl)amino-propan-2-yl]-5-hy-droxy-6-oxo-1,6-dihydro-pyrimidine-4-carboxyl-ate with dimethyl sulfate in dimethyl sulfoxide. The mol-ecule has a V-shaped structure, the phenyl and the pyrimidine rings making a dihedral angle of 43.1 (1)°.

Benzyl 2-benzyl-4-[(3aS,7aR)-2,3,3a,4,5,6,7,7a-octa-hydro-1H-isoindol-2-yl]-4-oxobutano-ate.

In the title compound, C(26)H(31)NO(3), the octa-hydro-1H-isoindole ring is not planar and the two rings are twisted with a C-C-C-C torsion angle of 73.6 (4)°. The six-membered ring has a chair conformation while the five-membered ring has an envelope conformation on the C-atom in position 7a.