Aminophenylboronic acid-modified nitrogen-doped graphene quantum dots and their applications in lysine sensing based on interplaying fluorescent mechanisms.

Using nitrogen-doped graphene quantum dots (N-GQDs) and 3-aminophenylboronic acid (APBA), a novel fluorescence nanosensor was developed. This nanosensor exhibits high selectivity and sensitivity for lysine detection. Its sensing mechanism involves the suppression of electron transfer from APBA to the N-GQDs unit, thereby inhibiting photoinduced electron transfer and initiating internal charge transfer.

Biocompatible tumor-targeted GQDs nanocatalyst for chemodynamic tumor therapy.

To deal with the complex tumor microenvironment (TME), chemodynamic therapy (CDT) has been developed, which uses nanocatalysts simulating peroxidase to convert high concentration hydrogen peroxide (HO) into highly toxic hydroxyl radicals (˙OH) and effectively kills tumor cells. Due to the low catalytic activity of traditional nanocatalysts, the present CDT treatment has to be combined with other anti-tumor therapies, which increases the complexity and uncertainty of the treatment. Thus, developing new nanocatalysts with stable and high enzymatic activity is the key point to CDT treatment.

Porous Graphene Oxide Films Prepared via the Breath-Figure Method: A Simple Strategy for Switching Access of Redox Species to an Electrode Surface.

Porous materials can be modified with physical barriers to control the transport of ions and molecules through channels via an external stimulus. Such capability has brought attention toward drug delivery, separation methods, nanofluidics, and point-of-care devices. In this context, gated platforms on which access to an electrode surface of species in solution can be reversibly hindered/unhindered on demand are appearing as promising materials for sensing and microfluidic switches.

Understanding the selective-sensing mechanism of lysine by fluorescent nanosensors based on graphene quantum dots.

The selectivity of single-amino acid nanosensors is still not well understood. Herein, the factors that govern graphene-based nanomaterials for the selective detection of lysine are reported to guide the design of single-amino acid nanosensors. Graphene quantum dots (GQDs), nitrogen-doped GQDs (N-GQDs), and nitrogen/sulfur co-doped GQDs (N,S-GQDs) were used to sense lysine.

A graphene oxide-based fluorescent sensor for recognition of glutamate in aqueous solutions and bovine serum.

A novel fluorescence probe based on graphene-aminofluorescein (GAF) for sensing glutamate is prepared by modifying graphene oxide (GO) with 5-aminofluorescein (AF), and shows high sensitivity and selectivity. The strong fluorescence of the GAF probe is quenched in the presence of glutamate, and the quenching exhibits a good linear relationship with the glutamate concentration within the range of 1-45 mg/L. In bovine serum, the accurate quantitation of glutamate is possible within the range of 6 mg/L to 30 mg/L.

Chlorine and temperature directed self-assembly of Mg-Ru2(ii,iii) carbonates and particle size dependent magnetic properties.

A series of heterometallic magnesium diruthenium(ii,iii) carbonates, namely K{Mg(H2O)6}2[Ru2(CO3)4Cl2]·4H2O (1), K2[{Mg(H2O)4}2Ru2(CO3)4(H2O)Cl]Cl2·2H2O (2), K[Mg(H2O)5Ru2(CO3)4]·5H2O (3) and K[Mg(H2O)4Ru2(CO3)4]·H2O (4), were synthesized from the reaction of Ru2(CO3)4(3-) and Mg(2+) in aqueous solution. Compound 1 is composed of ionic crystals with the Ru2(CO3)4Cl2(5-) : Mg(H2O)6(2+) : K(+) ratio of 1 : 2 : 1. Compound 2 consists of two dimensional layer structures, in which each octahedral environment Mg(H2O)4(2+) bonds to two [Ru2(CO3)4(H2O)Cl](4-) units in a cis manner forming a neutral square-grid layer {Mg(H2O)4Ru2(CO3)4(H2O)Cl}n.

Synthesis and adsorption performance of dithiocarbamate-modified glycidyl methacrylate starch.

The design of chelating polymers with fast complexation of the metal ions is particularly interest. In this work, the dithiocarbamate-modified glycidyl methacrylate starch was synthesized and characterized by FT-IR, (13)C NMR and XRD spectra. Its sorption performance for heavy metals fixation was studied.

Optical turn-on sensor based on graphene oxide for selective detection of D-glucosamine.

By incorporating the well-known fluorophore 8-aminoquinoline into graphene oxide, we have successfully prepared a turn-on fluorescent sensor capable of specific detection of D-glucosamine with a high selectivity and sensitivity. This methodology provides a new concept for the design and development of highly selective and sensitive turn-on optical sensors for selective detection of aminosaccharides and many other biomolecules.

Application of dithiocarbamate-modified starch for dyes removal from aqueous solutions.

The present study shows that the dithiocarbamate-modified starch (DTCS) is a commercially promising sorbent for the removal of anionic dyes from aqueous solutions. It is more effective than activated carbon for this purpose. At the appropriate solution pH of 4, kinetic studies indicate that the sorption of the dyes tends to follow pseudo-first-order equation.

Behaviors and mechanism of acid dyes sorption onto diethylenetriamine-modified native and enzymatic hydrolysis starch.

In this paper, different starches were modified by diethylenetriamine. The native starch reacted with diethylenetriamine giving CAS, whereas the enzymatic hydrolysis starch was modified by diethylenetriamine producing CAES. Adsorption capacities of CAES for four acid dyes, namely, Acid orange 7 (AO7), Acid orange 10 (AO10), Acid green 25 (AG25) and Acid red 18 (AR18) have been determined to be 2.

Equilibrium and molecular mechanism of anionic dyes adsorption onto copper(II) complex of dithiocarbamate-modified starch.

The assembly of dyes molecules on metal-polymer complexes is of interest due to their potential applications in photovoltaic cell, separation, and wastewater treatment. In the present work, the interaction of anionic dyes (acid orange 7, acid orange 10, acid green 25, and acid red 18) with the copper(II) complex of dithiocarbamate-modified starch (DTCSCu) was investigated. The sorption studies showed that the interaction mechanism was based on chelating adsorption.

Ethylenediamine modified starch as biosorbent for acid dyes.

This work investigated the sorption performance of the ethylenediamine modified starch (CAS) for the removal of acid dyes from aqueous solutions. The influence of pH on adsorption of acid orange 10 (AO10), acid green 25 (AG25) and amido black 10B (AB10B) was evaluated. The sorption kinetics, equilibrium uptake and desorption of the loaded dyes in sodium sulfate solution were studied.

[Spectra study of a sodion triethylenetetramine-bisdithiocarbamate and its complexes with heavy metal ions].

A sodion triethylenetetramine-bisdithiocarbamate (DTC-TETA) and its complexes with heavy metal ions were investigated by FTIR, UV, FAAS and elemental analysis, respectively. The FTIR spectrum of DTC-TETA showed strong absorption peaks at 1 461-1 388 cm(-1) and 1 174-996 cm(-1) which were attributed to partly double bonds of C-N and C-S, respectively. The UV spectrum of DTC-TETA had two absorption peaks at 265 and 290 nm, assigned to pi-pi* transition of N.

[Spectra characteristics of an aminated glucose and its complex with Cu(II)].

Characteristics of an aminated glucose and its complex with Cu (II) were investigated by FTIR, 1H-NMR and UV spectroscopy, respectively. Compared with glucose, the FTIR spectrum of an aminated glucose showed a moderate peak at 1 629-1 608 cm(-1) which was attributed to deltaNH vibration, suggesting that glucose reacted with ethylenediamine. The 1H-NMR spectrum of an aminated glucose demonstrated the signal of the C1 hydroxy proton and one of the amino proton at 4.

Syntheses, structures, and magnetic properties of unusual nonlinear polynuclear copper(II) complexes containing derivatives of 1,2,4-triazole and pivalate ligands.

Novel polynuclear Cu(II) complexes containing derivatives of 1,2,4-trizaole and pivalate ligands, [Cu(3)(mu(3)-OH)(mu-adetrz)(2)(piv)(5)(H(2)O)].6.5H(2)O (1) (adetrz = 4-amino-3,5-diethyl-1,2,4-triazole, piv = pivalate), [Cu(4)(mu(3)-OH)(2)(mu-atrz)(2)(mu-piv)(4)(piv)(2)].