Publications by authors named "Xin-zhen Du"

Sample pretreatment technology plays a vital role in the analysis of complex samples and is key to the entire analytical process. Its main purpose is to separate the substance to be measured from the sample matrix or interfering substances in the sample and to achieve a state in which the instrument can be analyzed and detected. Traditional sample pretreatment techniques include liquid-liquid extraction, liquid-solid extraction, precipitation separation, solvent volatilization-rotary evaporation, filtration, and centrifugation.

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Ribose plays an important role in the process of life. Excessive ribose in the human cerebrospinal fluid or urine can be used as an early diagnostic marker of leukoencephalopathy. Fluorinated phenylboronic acid combined with F NMR spectroscopy was a powerful method for molecular recognition.

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Glucose is a significant analyte both in biology and biomedical science, it is of great importance to selectively detect glucose both in body fluids and complex mixture. In this study, a simple F NMR based sensor was synthesized easily, which exhibited a high selectivity and robust anti-interference ability toward glucose detection both in a mixture containing up to 10 saccharides and human urine samples without any pretreatment. Combined with this sensor system, glucose could be well detected in human urine samples and the limit of detection was 0.

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Article Synopsis
  • A new method for extracting and quantifying four polycyclic aromatic hydrocarbons (PAHs) from water samples using microextraction with a special coated stainless steel wire has been developed, integrating this with High-Performance Liquid Chromatography (HPLC).
  • The coating consists of phenyl-functionalized mesoporous materials, which enhance extraction efficiency due to their high porosity and surface area.
  • Various factors affecting extraction efficiency (like temperature and stirring rate) were optimized, resulting in a detection limit of 0.32 to 2.44 ng/L, and the method displayed a relative standard deviation (RSD) of less than 4.10%.
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Mesoporous materials were employed as fast, sensitive and efficient fiber coatings of solid-phase microextraction (SPME) for the first time. Three micrometer as-synthesized C(16)-MCM-41 particles were immobilized onto stainless steel wire with 100mum coating thickness. In combination with high performance liquid chromatography (HPLC), extraction efficiency and selectivity of C(16)-MCM-41 were investigated using aromatic hydrocarbons.

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Objective: To study the chemical constituents of Myricaria bracteata.

Method: The chemical constituents were isolated by silica gel column chromatography and the structures were elucidated by spectroscopic methods.

Result: Eleven compounds were obtained and identified as rhamnetin, 3,5,4'-trihydroxy-7,3'-dimethoxyflavone, 3,5,4'-trihydroxy-7-methoxyflavone, quercetin-3-O-alpha-L-rhamnopyranoside, kaempferol, quercetin, chrysoerio, gallic acid, gallic acid ethylester, beta-sitosterol, daucosterol.

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Room-temperature phosphorescence of 1-BrN induced by a combination of OPE-10 and Triton X-100 with beta-CD was comparatively studied. In terms of molecular size and dimensions of beta-CD, the octyl group and phenyl group of OPE-10 and Triton X-100 were incorporated into the cavity of beta-CD and the complexes with the stoichiometry of 1:1 were formed. The removal of water molecules inside the cavity results in a greater apolar interior.

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A rapid and simple method for the study of the acupuncture effect on monoamine transmitters and related compounds in rabbit plasma and brain tissue by high performance liquid chromatography with electrochemical detection was developed. An ODS column was selected as the separation column at 25 degrees C, and pH 4.50, 0.

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