Confined synthesis of g-CN modified porous carbons for efficient removal of Cd ions.

Carbon nitride (CN) nanosheets have excellent adsorption capacity, environmental friendliness, and high stability for heavy metal removal. However, its application in Cd-polluted soil is difficult as aggregation induces the specific surface area to substantially decrease. In this study, a series of CN nanosheet-modified porous carbons (CN/PC-X) were prepared by a simple one-step calcination of mixed aerogels with different mass ratios (X) of carboxymethyl cellulose (CMC) and melamine.

A sensitive ratiometric fluorescent sensor based on carbon dots and CdTe quantum dots for visual detection of biogenic amines in food samples.

A novel dual-emission ratiometric fluorescent sensor for biogenic amines (BAs) was prepared by simple mixing blue fluorescent carbon dots (CDs) and yellow fluorescent CdTe quantum dots (CdTe QDs). Based on different sensitive properties of pH, CdTe QDs and CDs were used as the response signal and internal reference signal, respectively. The developed ratiometric fluorescent sensor achieved quantitative analysis of eight kinds of BAs with rapid response (30 s) and low limits of detection (1.

Regenerable magnetic aminated lignin/FeO/La(OH) adsorbents for the effective removal of phosphate and glyphosate.

Phosphates and organophosphorus cause environmental pollution, and excessive phosphate leads to water eutrophication. Glyphosate, an organophosphorus herbicide, harms the environment and human health. In this study, regenerable magnetic AL/FeO/La(OH) adsorbents were developed by modifying FeO and La(OH) on aminated lignin (AL) for phosphate and glyphosate removal.

Interactions between gold, thiol and As(iii) for colorimetric sensing.

As(iii) or arsenite is extremely toxic, and various colorimetric sensors were reported for its on-site detection. A highly cited example was based on gold nanoparticles (AuNPs) modified with a few thiol-containing compounds including dithiothreitol (DTT), reduced glutathione (GSH), and cysteine (Cys). As(iii) was believed to crosslink these surface ligands to aggregate AuNPs and produce a red-to-blue color change.

A Facile Colorimetric Sensor for 6-Mercaptopurine Based on Silver Nanoparticles.

A facile colorimetric method was developed for detecting 6-mercaptopurine (6-MP) using silver nanoparticles (AgNPs). The addition of 6-MP to AgNPs led to the aggregation of AgNPs with a color change from yellow to brown. The ratio between the absorbance at 394 and 530 nm (A/A) was used for a quantitative analysis of 6-MP.

Photoelectrochemical biosensor for HEN1 RNA methyltransferase detection using peroxidase mimics PtCu NFs and poly(U) polymerase-mediated RNA extension.

2'-O-methyl group on the 3' terminal nucleotide in plant microRNAs, as one kind of RNA methylations, is caused by HEN1 RNA methyltransferase (HENMT1), which is thought to be crucial for ribosome biogenesis and function. Herein, a simple and label-free PEC biosensing method was proposed for assay of HENMT1 activity and inhibitor screening based on peroxidase mimic PtCu nanoframes (PtCu NFs) catalytic signal amplification. In this work, MoS@Graphene quantum dots/Phosphorus-doped rodlike carbon nitride (MoS@GQDs/P-RCN) heterojunction was used as photoactive materials.

Ultrasensitive electrochemiluminescence immunosensor for 5-hydroxymethylcytosine detection based on FeO@SiO nanoparticles and PAMAM dendrimers.

An ultrasensitive sandwiched electrochemiluminescence (ECL) immunosensor was developed for 5-hydroxymethylcytosine (5hmC) detection in genomic DNA by using FeO@SiO core-shell magnetic nanomaterial as a immobilization matrix for anti-5hmC antibody, PAMAM conjugated avidin and Ru(bpy)(phen-5-NH)(PF) as signal amplification unit. Importantly, FeO@SiO nanoparticles were verified to not only possess enormous surface for loading antibody by amido link, but also exhibit excellent bioactivity. With the dual signal amplification strategy, the ECL immunosensor showed wide detection range from 0.

Facile colorimetric detection of Hg2+ based on anti-aggregation of silver nanoparticles.

This paper describes an investigation of a facile colorimetric sensor for Hg(2+) in aqueous solution based on the anti-aggregation of silver nanoparticles (AgNPs). In the absence of Hg(2+), the addition of 6-Thioguanine to AgNPs solution led to the aggregation of AgNPs, resulting in a color change from yellow to brown with a red shift of absorption spectra. However, the presence of Hg(2+) inhibited the 6-Thioguanine-induced aggregation of AgNPs accompanying with a color change from brown to yellow.

Magnetic nanoparticles and quantum dots co-loaded imprinted matrix for pentachlorophenol.

In this study, an imprinted silica matrix of pentachlorophenol (PCP) co-loaded with Fe(3)O(4) nanoparticles and ZnS:Mn(2+) quantum dots (QDs) was fabricated. The introduction of Fe(3)O(4) nanoparticles to the imprinted matrix provided an easy way to separate PCP under an external magnetic field. ZnS:Mn(2+) QDs offered a readout signal to monitor the amount of PCP bound to the imprinted matrix and evaluate the efficiency of imprinting.

A colorimetric and surface-enhanced Raman scattering dual-signal sensor for Hg2+ based on Bismuthiol II-capped gold nanoparticles.

The addition of Bismuthiol II to the gold nanoparticles (AuNPs) solution led to the aggregation of AuNPs with a color change from red to blue. As a result, hot spots were formed and strong surface-enhanced Raman scattering (SERS) signal of Bismuthiol II was observed. However, the Bismuthiol II-induced aggregation of AuNPs could be reversed by Hg(2+) in the system, accompanied by a remarkable color change from blue to red.

Synthesis of a β-cyclodextrin-modified Ag film by the galvanic displacement on copper foil for SERS detection of PCBs.

A mono-6-thio-β-cyclodextrin-modified silver film was synthesized via galvanic displacement on copper foil. The prepared silver films could enrich non-polar polychlorinated biphenyls (PCBs) molecules from hydrophilic phase using thiolate β-cyclodextrins (SH-β-CDs) as receptors. The components of as-prepared Ag-coated-Cu (Ag-Cu) film were confirmed by powder X-ray diffraction (XRD).

Facile synthesis of N-acetyl-L-cysteine capped ZnS quantum dots as an eco-friendly fluorescence sensor for Hg2+.

This paper described an investigation of a novel eco-friendly fluorescence sensor for Hg(2+) ions based on N-acetyl-l-cysteine (NAC)-capped ZnS quantum dots (QDs) in aqueous solution. By using safe and low-cost materials, ZnS QDs modified by NAC were easily synthesized in aqueous medium via a one-step method. The quantitative detection of Hg(2+) ions was developed based on fluorescence quenching of ZnS QDs with high sensitivity and selectivity.