Facile fabrication of naphthalene-functionalized magnetic nanoparticles for efficient extraction of polycyclic aromatic hydrocarbons from environmental water and fish samples.

In this study, naphthalene-modified magnetic nanoparticles (FeO@Nap) were simply prepared based on specific chelation interaction between phosphate groups and metal ions on FeO surface. The resultant FeO@Nap were characterized by FTIR, BET, SEM, TEM, NAM, TGA, and VSM techniques. With FeO@Nap as adsorbent, the polycyclic aromatic hydrocarbons (PAHs) were efficiently extracted by magnetic solid-phase extraction (MSPE) from environmental water and fish samples through the π-π interaction between modified naphthalene groups and PAHs, followed by their determination by GC-MS/MS.

Carbonized loofah sponge-based solid-phase extraction of benzo[]pyrene from fish followed by liquid chromatography-ultraviolet detection.

A simple and sensitive method combining solid-phase extraction (SPE) and high-performance liquid chromatography-ultraviolet detection (HPLC-UV) was developed for the determination of benzo[]pyrene (BaP) in fish. Loofah sponge (LS) was carbonized and used as an SPE adsorbent. Carbonization decreased the polarity of LS and enhanced its aromaticity.

Flowerlike Ni-NiO composite as magnetic solid-phase extraction sorbent for analysis of carbendazim and thiabendazole in edible vegetable oils by liquid chromatography-mass spectrometry.

A rapid, selective, and sensitive method was developed for the detection of carbendazim and thiabendazole in edible vegetable oil. Two benzimidazole analytes were pre-concentrated by magnetic solid phase extraction (MSPE) using flowerlike Ni-NiO composite as sorbents and followed by LC-MS/MS analysis. The flowerlike Ni-NiO composite sorbent displayed a high affinity towards benzimidazole analytes due to the reversible coordination interaction between the Ni(Ⅱ) ion and the electron-donating imidazole group.

A boronic acid-modified C derivatization reagent for the rapid detection of 3-monochloropropane-1,2-diol using matrix-assisted laser desorption/ionization-mass spectrometry.

Rationale: 3-Monochloropropane-1,2-diol (3-MCPD) is a well-known contaminant formed in food thermal processing, which could be found in a variety of foodstuffs. Due to its potential carcinogenicity, it was essential to quickly develop a rapid and high-throughput analytical method to monitor 3-MCPD in foodstuffs, which is described in this study.

Methods: 3-MCPD was extracted from foodstuffs and then was derivatized with a boronic acid-modified C (B-C ) through the boronic acid-diol reaction.

Boron Isotope Tag-Assisted Ultrahigh-Performance Liquid Chromatography Coupled with High-Resolution Mass Spectrometry for Discovery and Annotation of -Diol-Containing Metabolites.

-Diol-containing metabolites are widely distributed in living organisms, and they participate in the regulation of various important biological activities. The profiling of -diol-containing metabolites could help us in fully understanding their functions. In this work, based on the characteristic isotope pattern of boron, we employed a boronic acid reagent as the isotope tag to establish a sensitive and selective liquid chromatography-high-resolution mass spectrometry method for the screening and annotation of -diol-containing metabolites in biological samples.

C-based chemical labeling strategy for the determination of polyamines in biological samples using matrix-assisted laser desorption/ionization mass spectrometry.

Bioactive polyamines play important roles in many biological processes such as gene expression, cell growth, protein synthesis, and signal transduction. Accurate determination of polyamines is helpful for studying their biological functions. Herein, a C-based chemical labeling strategy was proposed for the determination of polyamines (putrescine, cadaverine, spermidine, and spermine) in biological samples using matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS).

Comprehensive Analysis of Volatile Compounds in Mouthpiece Cigarette Adhesive by Coupling Headspace with Gas Chromatography-Mass Spectrometry.

Background: Some volatile compounds in mouthpiece cigarette adhesive emit irritating odors and affect the taste of smoking cigarettes. Therefore, it is necessary to monitor the volatile compounds in mouthpiece cigarette adhesive.

Objectives: A rapid and simple analytical method of volatile compounds in mouthpiece cigarette adhesive was established.

Preparation of zirconium arsenate-modified monolithic column for selective enrichment of phosphopeptides.

Protein phosphorylation is a crucial posttranslational modification for the regulation of many different biological functions. Selective enrichment of phosphopeptides from the complex biological samples is an essential step for the mass spectrometry analysis of protein phosphorylation. In this study, an arsenate functionalized monolithic column was first prepared by a single-step copolymerization of p-methacryloylaminophenylarsonic acid and ethylene dimethacrylate.

Development of C60-based labeling reagents for the determination of low-molecular-weight compounds by matrix assisted laser desorption ionization mass spectrometry (II): Determination of thiols in human serum.

Perturbation of thiol homeostasis in biological fluids are thought to be associated with several diseases, and reliable analytical methods for the determination of low molecular weight (LMW) thiols in human plasma or serum are thus required. In this study, a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) method is described for high throughput determination of four LMW thiols (glutathione, cysteine, homocysteine and cysteinylglycine) in human serum. It is based on the use of a bromoacetyl functionalized C60 (Br-C60) as a derivatization reagent to label thiols.

An investigation of template anchoring strategy for molecularly imprinting materials based on nanomagnetic polyhedral oligomeric silsesquioxanes composites.

A template anchoring strategy for high performance molecularly imprinting materials (MI-materials) was displayed in the present work, which involved efficient usage of template molecules with the aid of functional monomer grafted on the support. The imprinting polymerization process was carried out on the surface of carboxyl functionalized FeO@POSS (FeO@POSS-COOH) anchoring with tetracycline templates as a demonstration. In this strategy, FeO@POSS-COOH was first prepared via a simple copolymerization between methacrylic acid (MAA) and the residual end vinyl groups of FeO@POSS.

Profiling of benzimidazoles and related metabolites in pig serum based on SiO@NiO solid-phase extraction combined precursor ion scan with high resolution orbitrap mass spectrometry.

Benzimidazoles (BZDs) are widely used veterinary drugs in the domestic food-producing animals, resulting in the metabolism of BZDs and the harmful metabolites residues in some foods. However, some BZD metabolites are unknown and so it is important to discover new metabolites to expand detection targets. For these reasons, a sensitive and selective strategy was designed to identify BZD metabolites in the serum of pigs after oral administration of albendazole, fenbendazole and thiabendazole, respectively.

Cu(Ⅱ) triggering redox-regulated anti-aggregation of gold nanoparticles for ultrasensitive visual sensing of iodide.

In this study, we proposed a novel anti-aggregation of gold nanoparticles (AuNPs) strategy for colorimetric sensing of iodide ions (I) regulated by the redox reaction between the target ions and the ion cross-linking agent. Cu as interlinking ion can induce aggregation of arginine capped AuNPs (Arg-AuNPs) due to the formation of Arg-Cu-Arg analogous structure resulting from the chelation between Cu and arginine, with a clear color change of solution from red to blue. In the presence of I, however, Cu would be readily reduced owing to the formation of CuI, AuNPs underwent a transformation from an aggregation to a dispersion state depending on the concentration of I, leading color changes from blue to red.

[Preparation of zirconia nanoparticles deposited cotton fibers and their application in the rapid enrichment of phosphopeptides].

A kind of cotton-based fibrous adsorbent, zirconia nanoparticles coated cotton fiber (ZrO-CF), was successfully prepared by liquid-phase deposition of zirconia nanoparticles on the surface of cotton fiber. And the ZrO-CF fibrous adsorbent was packed in pipet tips for the enrichment of phosphopeptide by pipetting up and down within 2 min, which was simple and fast. Nine phosphopeptides were identified from the digestion of -casein after ZrO-CF extraction.

Preparation of polymer monolithic column functionalized by arsonic acid groups for mixed-mode capillary liquid chromatography.

A mixed-mode polymer monolithic column functionalized by arsonic acid groups was prepared by single-step in situ copolymerization of monomers p-methacryloylaminophenylarsonic acid (p-MAPHA) and pentaerythritol triacrylate (PETA). The prepared poly(p-MAPHA-co-PETA) monolithic column has a homogeneous monolithic structure with good permeability and mechanical stability. Zeta potential measurements reveal that the monolithic stationary phase holds a negative surface charge when the mobile phase resides in the pH range of 3.

Facile synthesis of a boronate affinity sorbent from mesoporous nanomagnetic polyhedral oligomeric silsesquioxanes composite and its application for enrichment of catecholamines in human urine.

A boronate-decorated nanomagnetic organic-inorganic hybrid material was facilely synthesized by utilizing the nanomagnetic polyhedral oligomeric silsesquioxanes (POSS) composite (FeO@POSS) as the base platform. A simple copolymerization occurred between 3-acrylamidophenylboronic acid (AAPBA) and the residual end vinyl groups supplied by the substrate. Here the special emphasis was placed on the octavinyl POSS, which not only acted as the building blocks for a hybrid architecture but also facilitated the process of grafting boronate groups onto the surface of POSS based nanomagnetic composite (FeO@POSS).

Nickel Oxide Nanoparticle-Deposited Silica Composite Solid-Phase Extraction for Benzimidazole Residue Analysis in Milk and Eggs by Liquid Chromatography-Mass Spectrometry.

A novel nickel oxide nanoparticle-deposited silica (SiO2@NiO) composite was prepared via liquid-phase deposition (LPD) and then employed as a solid-phase extraction (SPE) sorbent. When the SPE was coupled with liquid chromatography-electrospray ionization mass spectrometry (LC-ESI/MS) analysis, an analytical platform for the sensitive determination of benzimidazole residues in egg and milk was established. The limits of detection of nine benzimidazoles were in the range of 0.

Magnetic solid phase extraction coupled with desorption corona beam ionization-mass spectrometry for rapid analysis of antidepressants in human body fluids.

Ambient ionization techniques show good potential in rapid analysis of target compounds. However, a direct application of these ambient ionization techniques for the determination of analytes in a complex matrix is difficult due to the matrix interference and ion suppression. To resolve this problem, here we developed a strategy by coupling magnetic solid phase extraction (MSPE) with desorption corona beam ionization (DCBI)-mass spectrometry (MS).

Profiling of aldehyde-containing compounds by stable isotope labelling-assisted mass spectrometry analysis.

We developed a strategy for non-targeted profiling of aldehyde-containing compounds by stable isotope labelling in combination with liquid chromatography-double neutral loss scan-mass spectrometry (SIL-LC-DNLS-MS) analysis. A pair of stable isotope labelling reagents (4-(2-(trimethylammonio)ethoxy)benzenaminium halide, 4-APC and d4-4-(2-(trimethylammonio)ethoxy)benzenaminium halide, 4-APC-d4) that can selectively label aldehyde-containing compounds were synthesized. The 4-APC and 4-APC-d4 labelled compounds were capable of generating two characteristic neutral fragments of 87 Da and 91 Da, respectively, under collision induced dissociation (CID).

Magnetic "one-step" quick, easy, cheap, effective, rugged and safe method for the fast determination of pesticide residues in freshly squeezed juice.

A "one-step" quick, easy, cheap, effective, rugged and safe (QuEChERS) method was proposed for pesticide residue analysis in freshly squeezed juice of fruits and vegetables. In this method, a new magnetic adsorbent prepared by simple physical blending was adopt, which could endow the sample mixture with magnetic separability. To achieve the best performance of the modified QuEChERS towards target analytes, the amounts of adsorbents were investigated.

Use of Pollen Solid-Phase Extraction for the Determination of trans-Resveratrol in Peanut Oils.

In this study, a simple and convenient method for the determination of trans-resveratrol (TRA) in peanut oils based on pollen grain solid-phase extraction (SPE) was developed. Pollen grains were used as normal-phase SPE sorbent to separate TRA from peanut oils for the first time. As a naturally occurring material, pollen grains exhibited an excellent adsorption capacity for polyphenolic compounds due to their particular functional structures such as hydroxyl groups, saturated and unsaturated aliphatic chains with aromatics.

Using pollen grains as novel hydrophilic solid-phase extraction sorbents for the simultaneous determination of 16 plant growth regulators.

In this article, pollen grains were for the first time used as a hydrophilic solid-phase extraction (HILIC-SPE) sorbent for the determination of 16 plant growth regulators (PGRs) in fruits and vegetables. Fourier transform infrared spectroscopy (FT-IR), scanning electronic microscopy (SEM) and nitrogen sorption porosimetry (NSP) were used to investigate the chemical structure and the surface properties of the pollen grains. Pollen grains exhibited an excellent adsorption capacity for some polar compounds due to their particular functional groups.

Sequential enrichment with titania-coated magnetic mesoporous hollow silica microspheres and zirconium arsenate-modified magnetic nanoparticles for the study of phosphoproteome of HL60 cells.

As one of the most important types of post-translational modifications, reversible phosphorylation of proteins plays crucial roles in a large number of biological processes. However, owing to the relatively low abundance and dynamic nature of phosphorylation and the presence of the unphosphorylated peptides in large excess, phosphopeptide enrichment is indispensable in large-scale phosphoproteomic analysis. Metal oxides including titanium dioxide have become prominent affinity materials to enrich phosphopeptides prior to their analysis using liquid chromatography-mass spectrometry (LC-MS).

Fabrication of enrofloxacin imprinted organic-inorganic hybrid mesoporous sorbent from nanomagnetic polyhedral oligomeric silsesquioxanes for the selective extraction of fluoroquinolones in milk samples.

This paper reports a nanomagnetic polyhedral oligomeric silsesquioxanes (POSS)-directing strategy toward construction of molecularly imprinted hybrid materials for antibiotic residues determination in milk samples. The imprinted polymeric layer was facilely obtained through the copolymerization of active vinyl groups present on the nanomagnetic POSS (Fe3O4@POSS) surface and functional monomer (methacrylic acid) binding with template (enrofloxacin). Herein, the octavinyl POSS acted as not only the building blocks for hybrid rigid architectures but also the cross-linker for the formation of effective recognition sites during the imprinting process.

Construction of a portable sample preparation device with a magnetic poly(methacrylic acid-co-ethylene dimethacrylate) monolith as the extraction medium and its application in the enrichment of UV filters in water samples.

A portable sample preparation device with a magnetic polymer monolith as the extraction medium was constructed. The monolith was synthesized by polymerizing methacrylic acid and ethylene dimethacrylate around a cylindrical magnet. In this way, the monolith with a magnetic core could be readily attached to the extraction device by magnetism.