Dual-Mode Method for the Sensitive Detection of β-Secretase (BACE1) Based on Surface-Enhanced Raman Scattering and Dark-Field Microscopy.

β-Secretase (BACE1), a key enzyme to producing neurotoxic β-amyloid, is a potential biomarker of Alzheimer's disease (AD). Developing a sensitive and efficient detection method for BACE1 activity is significant for AD progression evaluation. Due to the poor cleavage efficiency and acidic working conditions of BACE1, developing probes with high stability and strong signals is challenging for its detection.

Quantification of amino-PAHs in human urine using UHPLC- hybrid quadrupole orbitrap high resolution MS (Q-orbitrap-HRMS): Assessing potential carcinogenic risks of Nitro-PAHs.

Considering only parent polycyclic aromatic hydrocarbons (PAHs), such as benzo(a)pyrene as a representative compound, may underestimate the carcinogenic risk of polycyclic aromatic compounds (PACs). Nitrated polycyclic aromatic hydrocarbons (nitro-PAHs), known for their higher toxicity relative to parent PAHs, are widely present in the environment. In this study, a novel, highly sensitive, and accurate method utilizing ultra-performance liquid chromatography coupled with hybrid quadrupole Orbitrap high resolution MS (Q-Orbitrap-HRMS) was developed to quantify 15 amino-PAHs, which are metabolites of nitro-PAHs, in human urine samples.

Dual-mode biosensor for monoamine oxidase B activity detection based on electrochemistry and surface-enhanced Raman scattering.

Background: Alzheimer's disease (AD) is a neurodegenerative disease that threatens the physical health of elderly people. As a potential biomarker for AD, the assessment of monoamine oxidase B (MAO-B) activity is essential for the early diagnosis of AD. Prussian blue nanoparticles (PB NPs) are metal-organic framework materials that can react with hydrogen peroxide (HO) at low overpotential to produce a reduction current.

Quantitative Detection of Micro- and Nanoplastics (≥300 nm) in Human Urine Using Double-Shot Py-GC/MS with Internal Standard Calibration.

The rapid increase in plastic production and consumption has intensified research into human exposure to micro- and nanoplastics (MNPs) and their health effects. This study quantitatively assessed MNP internal exposure levels in non-invasive human samples, focusing on the four most common types of MNPs (≥300 nm): polyethylene terephthalate (PET), polypropylene (PP), low-density polyethylene (LDPE), and polystyrene (PS). Urine samples from 18 volunteers (4 males, 14 females) were analyzed using pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) with P(E-C) as an internal standard.

A Sensitive SERS Sensor for Simultaneous Detection of Two Potential Biomarkers of Alzheimer's Disease: AChE and MAO-B.

Monoamine oxidase B (MAO-B) and acetylcholinesterase (AChE) are potential biomarkers for Alzheimer's disease (AD). However, few methods exist to detect both AChE and MAO-B simultaneously. In this study, we developed a SERS sensor for the simultaneous detection of AChE and MAO-B based on the one-pot reaction system, which provided more valuable information for early AD diagnosis.

Sensitive SERS detection of trace methamphetamine in complex samples through sharp-spiked gold nanostructure.

Taking a massive overdose of methamphetamine (MAMP), which is one of the most prevalent illicit drugs in the world, will stimulate central nervous system, impair both physical and mental health and even lead to death. Therefore, the rapid quantitative testing in the field of MAMP is of great importance to law enforcement agencies. In this study, a branched, sharp-spiked gold nanostructure, named AuNS@4-MBA, is successfully synthesized at room temperature.

Enhancing Biodegradation of Insoluble High Molecular Weight Polycyclic Aromatic Hydrocarbons in Macroemulsion (ME) Bioreactors with a Liquid-Liquid Interface.

Due to the low bioavailability and insolubility of high molecular weight polycyclic aromatic hydrocarbons (HMW-PAHs) in aqueous solutions, their degradation efficiency is significantly limited in wastewater treatment and environmental remediation. To address this challenge, we designed oil-in-water (O/W) macroemulsion (ME) bioreactors with mixed surfactants (Tween-80 and Triton X-100), -butanol, corn oil, and () to enhance the degradation efficiency of pyrene. Owing to the higher solubility of pyrene in MEs, it could be easily adsorbed onto hydrophobic groups on the cell surface.

Simultaneous determination of three strong polarity herbicides in tea by ion chromatography-triple quadrupole mass spectrometry.

Due to lack of chromogenic groups and fluorescence groups, high boiling point, high polarity, low volatility, and small molecular weight of glyphosate, glufosinate and bentazone, the detection of three analyses were limited in all kinds of food. Herein, a method for the simultaneous determination of glyphosate, glufosinate and bentazone in tea by ion chromatography tandem triple quadrupole mass spectrometry (IC-MS) was developed, which is without organic solvent and complex derivatization. The recoveries of three compounds in different teas (black tea, green tea, white tea) ranged from 80.

A core-molecule-shell Au@PATP@Ag nanorod for nicotine detection based on surface-enhanced Raman scattering technology.

Nicotine is an addictive substance often found in tobacco and cigarette smoke and excessive exposure to it can cause various diseases. Herein, core-molecule-shell gold/4-aminothiophenol/silver nanorods (Au@PATP@Ag NRs) were prepared for quantitative detection of nicotine by using surface-enhanced Raman scattering (SERS) technology. The obtained Au@PATP@Ag NRs showed an outstanding SERS effect due to the plasticity of their morphology and the bimetallic synergistic effect between the excellent stability of Au and the highly enhanced effect of Ag.

Sensitive detection of synthetic cannabinoids in human blood using magnetic polydopamine molecularly imprinted polymer nanocomposites.

Synthetic cannabinoids (SCs) are a series of artificial chemical substances with pharmacological properties similar to those of natural cannabinoids and their abuse poses a great risk to social security and human health. However, the highly sensitive detection of low concentrations of SCs in human serum remains a great challenge. In this work, we developed a highly sensitive, rapid and highly selective method for the detection of SCs in human serum.

Simultaneous determination of ten neonicotinoid insecticides and a metabolite in human whole blood by QuEChERS coupled with UPLC-Q Exactive orbitrap high-resolution mass spectrometry.

Since neonicotinoid insecticides are now the most extensively used insecticides worldwide, there are increasing cases of neonicotinoid poisoning. A rapid and sensitive method was developed for the determination of ten neonicotinoid insecticides and a metabolite 6-chloronicotinic acid in human whole blood. The types and amounts of extraction solvent, salting-out agent, and adsorbent in the QuEChERS method were optimized by comparing the absolute recoveries of 11 analytes.

Fabrication of flexible SERS substrate based on Au nanostars and PDMS for sensitive detection of Thiram residue in apple juice.

We developed a novel fabrication of flexible surface-enhanced Raman scattering (SERS) substrate to perform selective and sensitive determination of thiram residue in fruits and juices. Au nanostars (Au NSs) with multi-branching structure were self-assembled on aminated Polydimethylsiloxane (PDMS) slides by electrostatic interaction. By measuring the Thiram's characteristic peak intensity at 1371 cm, the SERS method could distinguish Thiram from other pesticide residues.

Determination of γ-hydroxybutyrate in human urine samples by ion exclusion and ion exchange two-dimensional chromatography system.

A two-dimensional ion chromatography system was developed for the determination of γ-hydroxybutyrate (GHB) in human urine samples. Ion exclusion chromatography was used in the first dimensional separation for elimination of urine matrices and detection of GHB above 10mgL, ion exchange chromatography was used in the second dimensional separation via column-switching technique for detection of GHB above 0.08mgL.

Octadecylamine-modified poly (glycidylmethacrylate-divinylbenzene) stationary phase for HPLC determination of N-nitrosamines.

Poly (glycidylmethacrylate-divinylbenzene) (Poly (GMA-DVB)) microspheres were prepared by the two-staged swelling and polymerization method, and modified with octadecylamine (ODA) to obtain ODA-poly (GMA-DVB) stationary phase for HPLC. The new material was characterized by scanning electron microscope, nitrogen adsorption-desorption measurement, Fourier transform infrared spectrum, elemental analysis and thermogravimetric analysis. The results showed that poly (GMA-DVB) microspheres had good monodispersity, porosity and ball shapes.

High-capacity anion exchangers based on poly (glycidylmethacrylate-divinylbenzene) microspheres for ion chromatography.

Poly (glycidylmethacrylate-divinylbenzene) microspheres were prepared by the two-staged swelling and polymerization method and applied to prepare anion exchange stationary phases. Methylamine, dimethylamine, trimethylamine, diethylamine and triethylamine were selected to prepare the quaternary ammonium groups of anion exchangers, respectively. The diameters and surface characteristics of microspheres were measured by scanning electron microscope and nitrogen adsorption-desorption measurements.

Preparation of poly(glycidylmethacrylate-divinylbenzene) weak acid cation exchange stationary phases with succinic anhydride, phthalic anhydride, and maleic anhydride for ion chromatography.

In this work, poly(glycidylmethacrylate-divinylbenzene) microspheres were prepared and applied for the preparation of weak acid cation exchange stationary phases. Succinic anhydride, phthalic anhydride, and maleic anhydride were selected as carboxylation reagents to prepare three weak acid cation exchangers by direct chemical derivatization reaction without solvent or catalyst. The diameters and dispersity of the microspheres were characterized by scanning electron microscopy; the amount of accessible epoxy groups and mechanical stability were also measured.

[Determination of glyphosate in heart blood of corpse by ion chromatography].

A method for the determination of glyphosate in human blood by ion chromatography was established. The protein in heart blood from a corpse was precipitated with acetonitrile. The large molecules and Cl(-) in the supernatant were removed by a Dionex OnGuard II RP column and a Dionex OnGuard II Ag column, respectively.