A comparative study of two thienopyrimidine Schiff base probes for sequential monitoring of Ga and Pd.

Two Schiff base probes (S1 and S2) were prepared and synthesized by incorporating thienopyrimidine into salicylaldehyde or 3-ethoxysalicylaldehyde individually, with the aim of detecting Ga and Pd sequentially. Upon chelation with Ga, S1 and S2 exhibited fluorescence enhancement in DMSO/HO buffer. Both S1-Ga and S2-Ga were quenched by Pd.

Thienopyrimidine-derived multifunctional fluorescence sensor for the detection of Cu, Fe, and PPi in different solvents.

Hydrazine substituted thienopyrimidine, a new fluorophore, was used to synthesize a novel Schiff base R1 as a chemosensor via the condensation with p-formyltriphenylamine, and the structure was confirmed using nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS) analysis. When treated with Cu in dimethylsulfoxide (DMSO)/HO buffer, R1 showed a phenomenon of fluorescence quenching, which was reversible with the action of ethylenediaminetetraacetic acid (EDTA). When treated with Fe in dimethylformamide (DMF)/HO buffer, R1 exhibited the same phenomenon, but fluorescence was recovered with inorganic pyrophosphate (PPi) quantitatively.

Electrochemical aptasensor based on gold nanoparticle decorated TiCT nanocomposites for chloramphenicol detection.

Using gold (Au) nanoparticle decorated TiCT (TiCT-Au) nanocomposites, a highly sensitive electrochemical aptasensor for the effective detection of chloramphenicol has been developed. As a two-dimensional layered material, the prepared composite not only provides high surface area, good conductivity, and thermal stability but also substantial binding sites for aptamers with high sensitivity and selectivity for the accurate determination of chloramphenicol. Interestingly, the conductivity and active sites were enhanced by freeze-drying TiCT and in situ formation of TiCT-Au nanocomposite.

A new Schiff base derived from 5-(thiophene-2-yl)oxazole as "off-on-off" fluorescence sensor for monitoring indium and ferric ions sequentially and its application.

A new Schiff base sensor (E)-N'-((8-hydroxy-2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinolin-9-yl)methylene)-5-(thiophen-2-yl)oxazole-4-carbohydrazide (TOQ) was synthesized and found to emit yellowish green fluorescence upon introduction of In. Furthermore, the resulting complex TOQ-In was quenched selectively by Fe. The detection limits of TOQ for In and Fe were 1.

Synthesis of Triblock Polycarboxylate Superplasticizers with Well-Defined Structure and Its Dispersing Performance in β-Hemihydrate Gypsum.

In this work, a novel ABA-type triblock polycarboxylate superplasticizers (PCEs) with well defined molecular structures were designed and synthesized, firstly, by reversible addition-fragmentation chain transfer (RAFT) polymerization, to explore the structure-property relationship PCEs in the β-hemihydrate gypsum (β-HH) system. Three PCEs with the same molecular weight and different structure were obtained by changing the feed ratio of the RAFT agent, initiator, and monomer. The effect of the chemical structure of PCEs on their dispersing property and water reduction capacity were assessed in gypsum by measuring the flowability of pastes and the adsorption ability of PCEs on gypsum.

A new sensor based on thieno[2,3-b]quinoline for the detection of In , Fe and F by different fluorescence behaviour.

Based on thieno[2,3-b]quinoline-2-carbohydrazide and salicylaldehyde, a novel fluorescent probe (L) was designed and synthesized. L could be used as a multifunctional sensor to sequentially detect In and Fe through fluorescence enhancement and fluorescence quenching in DMF/H O buffer solutions. At the same time, L had good anti-interference ability, which could still detect In and Fe well in the presence of other metal ions.

Expression and Biochemical Characterization of a Novel Marine Chitosanase from Suitable for Preparation of Chitobiose.

It is known that bioactivities of chitooligosaccharide (COS) are closely related to the degree of polymerization (DP); therefore, it is essential to prepare COS with controllable DP, such as chitobiose showing high antioxidant and antihyperlipidemia activities. In this study, BLAST, sequence alignment and phylogenetic analysis of characterized glycoside hydrolase (GH) 46 -chitosanases revealed that a chitosanase Sn1-CSN from was different from others. Sn1-CSN was overexpressed in , purified and characterized in detail.

A sensitive electrochemical DNA sensor for detecting Helicobacter pylori based on accordion-like TiCTx: a simple strategy.

A novel electrochemical DNA sensor was designed to detect Helicobacter pylori based on accordion-like TiCT. Here the multilayer TiCT obtained by DMSO delamination was used to modify the glass carbon electrode, with a large specific surface area and excellent conductivity. Au nanoparticles were supported on the modified electrode and worked as an effective carrier to fix the capture probe (cpDNA) with sulfhydryl group through the firm binding of Au-S bond.

Construction of a novel GQD based ratiometric fluorescent composite probe for viscosity detection.

Herein, a novel ratiometric fluorescent composite nanoprobe RV-1@GQDs-OH was developed based on OH-functionalized GQDs (GQDs-OH) and molecular probe (RV-1) viaπ-π stacking. Compared with the conventional "on-off" viscosity probes, RV-1@GQDs-OH can be successfully applied in living systems for the ratiometric detection of viscosity changes in the viscosity range of 0-600 cP.

Mesoporous silica hybridized by ordered mesoporous carbon for in-tube solid-phase microextraction.

To enhance the extraction performance, a mesoporous silica was modified with ordered mesoporous carbon for solid-phase microextraction. Three stainless-steel wires coated with the mesoporous material were placed in a polyetheretherketone tube for getting an extraction tube. The tube was coupled to high-performance liquid chromatography with diode array detector, and the online analysis system was constructed.

Surface Modification of Bentonite with Polymer Brushes and Its Application as an Efficient Adsorbent for the Removal of Hazardous Dye Orange I.

Poly(2-(dimethylamino)ethyl methacrylate)-grafted bentonite, marked as Bent-PDMAEMA, was designed and prepared by a surface-initiated atom transfer radical polymerization method for the first time in this study. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermal gravimetric analysis (TGA) were applied to characterize the structure of Bent-PDMAEMA, which resulted in the successful synthesis of Bent-PDMAEMA. As a cationic adsorbent, the designed Bent-PDMAEMA was used to remove dye Orange I from wastewater.

Carbon nanotubes functionalized mesoporous silica for in-tube solid-phase microextraction of polycyclic aromatic hydrocarbons.

A mesoporous silica was functionalized by carbon nanotubes to enhance the extraction performance. The mesoporous material was coated on stainless steel wires, and three wires were inserted inside of a polyetheretherketone tube for in-tube solid-phase microextraction. The tube was coupled to high-performance liquid chromatography with diode array detection to obtain online analytical system, then its extraction performance was evaluated using eight polycyclic aromatic hydrocarbons as the targets.

Ultra-Highly Efficient Removal of Methylene Blue Based on Graphene Oxide/TiO/Bentonite Sponge.

An ultra-highly efficient Graphene Oxide/TiO/Bentonite (GO/TiO/Bent) sponge was synthesized using an in situ hydrothermal method. GO/TiO/Bent sponge with a GO mass concentration of 10% exhibited the highest treatment efficiency of methylene blue (MB), combining adsorption and photocatalytic degradation, and achieved a maximum removal efficiency of 100% within about 70 min. To further prove the ultra-high removal capacity of the sponge, the concentration of MB in water increased to ten times the original concentration.

A selective "turn-on" sensor for recognizing In and Zn in respective systems based on imidazo[2,1-b]thiazole.

A new simple and easily synthesized multitarget sensor, (E)-N'-(4-(diethylamino)-2-hydroxybenzylidene)imidazo[2,1-b]thiazole-6-carbohydrazide (X), was designed and synthesized using imidazo[2,1-b]thiazole-6-carboxylic acid and 4-(diethylamino)-2-hydroxybenzaldehyde. X could be used as a sensor to detect In3+ in DMF-H2O buffer solution and detect Zn2+ in EtOH-H2O buffer solution through fluorescence enhancement with detection limits of 1.02 × 10-9 M and 5.

A Unique Approach to Development of a Multiratiometric Fluorescent Composite Probe for Multichannel Bioimaging.

Ratiometric fluorescent probes have shown great potential for optical sensing and have been widely used for bioimaging. However, due to extremely stringent molecular design, most conventional organic ratiometric fluorescent probes can only achieve one single ratio. Currently, the detection of a target in living systems in a multiratiometric manner is prominently challenging.

Ultrasensitive electrochemical detection of ochratoxin A based on signal amplification by one-pot synthesized flower-like PEDOT-AuNFs supported on a graphene oxide sponge.

To enhance the sensitivity of an aptasensor, a novel strategy was designed to develop an electrochemical aptasensor based on poly(3,4-ethylenedioxy thiophene)-gold nanoflower (PEDOT-AuNF) composites supported on a three-dimensional graphene oxide sponge (GOS). GOS with a three-dimensional sponge-like porous structure, exhibiting excellent electrical conductivity and a large surface area, provided the first amplification of the electrochemical signal for ochratoxin A (OTA) detection. PEDOT-AuNFs, synthesized by an ionic liquid-assisted one-pot method, presented a peculiar hierarchical flower-like structure, a high electroactive surface area, and more binding sites for immobilizing the aptamer molecules by the Au-S bonds.

Bentonite Modified by Allylamine Polymer for Adsorption of Amido Black 10B.

The main object of this work is to remove Amido black 10B using a new type of bentonite-based adsorbent with cationic groups by the modification of polyallyl amines between the interlayers of bentonite. Fourier transform infrared, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy were used to characterize the functionalized bentonite. A series of batch adsorption experiments were performed.

A ratiometric fluorescent composite nanomaterial for RNA detection based on graphene quantum dots and molecular probes.

RNA plays a central role in controlling cellular functions. Research of the content and distribution of RNA in living cells is of great significance to both biochemistry and biomedicine. However, ratiometric fluorescent probes for the detection of RNA in the cytoplasm and nucleoli are still rarely reported.

A fluorescent sensor for Zn(2+) and NO2(-) based on the rational control of C[double bond, length as m-dash]N isomerization.

A new strategy for the ultrasensitive sensing of cations and anions based on the control of C[double bond, length as m-dash]N isomerization has been developed. Imine-derived ligand is non-fluorescent due to the C[double bond, length as m-dash]N isomerization process, whereas its ternary complex with ZnCl2 is moderately fluorescent because of the partial inhibition of C[double bond, length as m-dash]N isomerization. Such a ternary complex can give a remarkable fluorescence increase when it interacts with nitrite because of the much more efficient suppression of C[double bond, length as m-dash]N isomerization.

Biodegradable Self-Assembled Nanoparticles of Galactose-Containing Amphiphilic Triblock Copolymers for Targeted Delivery of Paclitaxel to HepG2 Cells.

Biodegradable self-assembled polymeric nanoparticles (NPs) composed of poly(6-O-methacryloyl-D-galactopyranose)-b-poly(L-lactide)-b-poly(6-O-methacryloyl-D-galactopyranose) (PMAGP-b-PLA-b-PMAGP) are prepared as carriers for the hydrophobic anticancer drug paclitaxel (PTX), to achieve target delivery to hepatoma cells. PTX can be encapsulated by the NPs with various molar ratios of L-lactide (LA) and 6-O-methacryloyl-D-galactopyranose (MAGP) during the process of self-assembly, and the resulting NPs exhibit high drug loading efficacy and substantial stability in aqueous solution. The size, size distribution, and morphology of the NPs are characterized using a Zetasizer Nano ZS and transmission electron microscopy.

A novel signal amplification strategy of an electrochemical aptasensor for kanamycin, based on thionine functionalized graphene and hierarchical nanoporous PtCu.

An ultrasensitive electrochemical aptasensor for the quantitative detection of kanamycin antibiotic was fabricated based on a novel signal amplification strategy. This aptasensor was developed using thionine functionalized graphene (GR-TH) and hierarchical nanoporous (HNP) PtCu alloy as biosensing substrates for the first time. HNP-PtCu alloy with controllable bimodal ligament/pore distributions was successfully prepared by two-step dealloying of a well-designed PtCuAl precursor alloy combined with an annealing operation.

A fluorescent sensor with a detection level of pM for Cd(2+) and nM for Cu(2+) based on different mechanisms.

A fluorescent sensor L, which showed turn-on response towards Cd(2+) with a detection limit of 1.9 × 10(-12) mol L(-1) in acetonitrile-H2O buffer solution based on the PET process and turn-off response toward Cu(2+) with a detection limit of 4.9 × 10(-9) mol L(-1) in pure water at pH 3.

A novel electrochemical aptasensor for ultrasensitive detection of kanamycin based on MWCNTs-HMIMPF6 and nanoporous PtTi alloy.

A novel aptasensor based on a novel composite film consisting of multi-walled carbon nanotubes (MWCNTs), ionic liquid (IL) of 1-hexyl-3-methylimidazolium hexafluorophosphate (HMIMPF6), and nanoporous PtTi (NP-PtTi) alloy was constructed for ultrasensitive detection of kanamycin. The NP-PtTi alloy was successfully fabricated by a simple dealloying of PtTiAl source alloy in HCl solution. The NP-PtTi alloy has uniform interconnected network structure with specific surface area and was used to immobilize aptamer.

Hepatoma-targeting and pH-sensitive nanocarriers based on a novel D-galactopyranose copolymer for efficient drug delivery.

Smart nanoparticles based on the mechanisms of asialoglycoprotein (ASGP)-mediated endocytosis and pH-induced drug release were developed for the efficient treatment of hepatoma using a newly developed copolymer, methoxy-polyethylene glycols (PEG)-b-poly (d-galactopyranose) (MPEG-b-PMaIPG). The particles exhibited spherical shapes, uniform particle size distribution (100 ± 4.43 nm), negative zeta potential (-32.