Publications by authors named "Shuyun Zhu"

70 Publications

Fluorescent DNA-templated silver nanoclusters for highly sensitive detection of D-penicillamine.

Spectrochim Acta A Mol Biomol Spectrosc 2021 May 14;253:119584. Epub 2021 Feb 14.

School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, China. Electronic address:

Herein, fluorescent DNA-templated silver nanoclusters (DNA-AgNCs) with red emission were synthesized and utilized as novel probe to detect D-penicillamine (D-Pen) for the first time. D-Pen molecules contain a thiol which can combine with Ag to form a non-fluorescent ground state complex, inducing the aggregation of DNA-AgNCs followed by the fluorescence quenching. The quenching mechanism is well-studied and found to be a static quenching process. This method can detect D-Pen in the range of 0.025-0.7 μM with the detection limit as low as 8 nM, which is 1-3 orders of magnitude more sensitive than those based on other fluorescent nanoprobes. More importantly, the preparation procedure for DNA-AgNCs is fast and without the requirement of heavy metal ions. Thus, this detection strategy is time-saving and eco-friendly. Satisfactory recoveries have been acquired for monitoring D-Pen in human serum samples and pharmaceutical samples owing to the high sensitivity.
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http://dx.doi.org/10.1016/j.saa.2021.119584DOI Listing
May 2021

A ratiometric fluorescence assay for bleomycin based on dual-emissive chameleon DNA-templated silver nanoclusters.

Spectrochim Acta A Mol Biomol Spectrosc 2021 May 1;252:119521. Epub 2021 Feb 1.

School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, PR China. Electronic address:

The authors design dual-emissive DNA-templated silver nanoclusters (DNA-AgNCs) for ratiometric fluorescence sensing bleomycin (BLM) for the first time. A hairpin probe containing two different C-rich DNA templates at two terminals is used to synthesize chameleon DNA-AgNCs, which possess two emission peaks when they are in close proximity. A strong emission is founded at 622 nm (λex = 570 nm) while a weak one is located at 572 nm (λex = 504 nm). Meanwhile, the loop of this probe contains the scission site (5'-GC-3') of BLM. The loop can be cleaved into two parts by BLM-Fe(II) complex, inducing the two DNA-AgNCs away from each other. The fluorescence intensity at 572 nm and 622 nm increases and decreases, respectively. Such chameleon DNA-AgNCs exhibit an obvious fluorescence discoloration from orange to yellow. Therefore, a sensitive ratiometric fluorescent strategy for BLM detection has been proposed with the detection limit of 67 pM. Finally, this ratiometric method is used to detect BLM in serum samples.
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http://dx.doi.org/10.1016/j.saa.2021.119521DOI Listing
May 2021

Analysis of hydrochemical evolution in main discharge aquifers under mining disturbance and water source identification.

Environ Sci Pollut Res Int 2021 Jan 26. Epub 2021 Jan 26.

Peigou Coal Mine, Zhengzhou Coal Group Co., Ltd., Zhengzhou, 452382, Henan, People's Republic of China.

To discuss the hydrochemical evolution characteristics of the mining process of Peigou Coal Mine, based on the test results of 43 water samples collected at different times from three main discharge aquifers, namely, Carboniferous Taiyuan Formation limestone water (L + L water), Ordovician limestone water (including Taiyuan Formation L), and Permian main mining coal seam roof and floor sandstone water (roof and floor water), a hydrochemical evolution model of the mining disturbances since 2003 has been established. The carbonate and sulphate dissolution and pyrite oxidation in Ordovician limestone water significantly decreased and then increased in 2006, and silicate weathering was weak. The carbonate and sulphate dissolution, silicate weathering and pyrite oxidation of roof and floor sandstone water increased. At the same time, a water source identification model suitable for the Peigou Coal Mine was developed by comparing the Fisher discriminant and the BP (back propagation) neural network discriminant. The accuracy rates of Fisher discriminant and BP neural network discriminant are 81.40% and 83.72% respectively, which indicates that BP neural network is more accurate. Finally, the evolution of hydraulic connection between aquifers is analysed. We speculate that there is a fracture development channel between Ordovician limestone water and roof and floor water aquifers that is affected in 2005 by the mining disturbance. This study has significance for examining the hydrochemical evolution of groundwater in mines and acting as a guideline to prevent and control water inrushes.
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http://dx.doi.org/10.1007/s11356-021-12639-wDOI Listing
January 2021

Ce-triggered cascade reaction for ratiometric fluorescence detection of alendronate.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Apr 6;251:119437. Epub 2021 Jan 6.

School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, PR China. Electronic address:

A ratiometric fluorescence assay for alendronate (ALDS) has been designed with Ce-triggered cascade chromogenic reaction. This strategy involves three processes: (1) Ce oxidizes ascorbic acid (AA) into dehydroascorbic acid (DHAA), which then condenses with o-phenlenediamine (OPD) to generate fluorescent 3-(dihydroxyethyl)furo[3,4-b] quinoxaline-1-one (DFQ), presenting the maximum emission at 434 nm; (2) As oxidase-mimics, Ce can oxidize OPD into fluorescent 2,3-diaminophenazine (DAP) which shows a strong emission at 568 nm; (3) ALDS inhibits the oxidation ability of Ce towards OPD, thus inhibiting the generation of DAP. Accordingly, a homogeneous ratiometric fluorescence system with dual emission comes into being and the presence of ALDS can change the fluorescence intensity ratio obviously. With F/F as readout, ALDS can be detected sensitively with the detection limit of 30 nM. Moreover, this ratiometric method was used to analyze ALDS in both human serum and pharmaceutical samples.
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http://dx.doi.org/10.1016/j.saa.2021.119437DOI Listing
April 2021

12-Plex UHPLC-MS/MS analysis of sarcosine in human urine using integrated principle of multiplex tags chemical isotope labeling and selective imprint enriching.

Talanta 2021 Mar 19;224:121788. Epub 2020 Oct 19.

Beijing National Laboratory for Molecular Sciences, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, PR China.

Urinary sarcosine was considered to be a potential biomarker for prostate cancer (Pca). In this work, an integrated strategy of multiplex tags chemical isotope labeling (MTCIL) combined with magnetic dispersive solid phase extraction (MDSPE), was proposed for specific extraction and high-throughput determination of sarcosine by ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). In the past three months, we have developed 8-plex MTCIL reagents with excellent qualitative and quantitative performance. In this work, the multiplexing capacity of MTCIL reagents (MTCIL360/361/362/363/364/365/366/375/376/378/379/381) was increased 1.5-fold from 8-plex to 12-plex. MTCIL359 was prepared and used to label sarcosine standard as internal standard (IS). The structural analogue derivative (MTCIL373-sarcosine) of all targeted MTCIL-sarcosine derivatives was synthesized and used as a novel dummy template to prepare dummy magnetic molecularly imprinted polymers (DMMIPs). The integration of MTCIL and DMMIPs procedures were extremely favorable to excellent chromatographic separation and efficient mass spectrometric detection. The labeling efficiency, chromatographic retention and mass spectrometry responses of MTCIL reagents were consistent for sarcosine. In a single UHPLC-MS/MS run (2.0 min), this method can simultaneously quantify sarcosine in 12-plex urine samples and achieve unbiased concentrations comparison between different urine samples. Analytical parameters including linearity (R 0.989-0.997), detection limits (0.02 nM), precision (2.6-11.5%), accuracy (96.1-107.4%), matrix effect, labeling and extraction efficiency were carefully validated. The proposed method was successfully applied for urinary sarcosine determination of healthy male individuals and Pca patients. It was found that the sarcosine concentrations in these two groups were statistically extremely significantly different (P < 0.001). The developed method was a powerful analytical tool to substantially promote the analysis throughput and large-scale experiments about the potential biomarker research.
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http://dx.doi.org/10.1016/j.talanta.2020.121788DOI Listing
March 2021

13-Plex UHPLC-MS/MS Analysis of Hexanal and Heptanal Using Multiplex Tags Chemical Isotope Labeling Technology.

J Am Soc Mass Spectrom 2020 Sep 25;31(9):1965-1973. Epub 2020 Aug 25.

Beijing National Laboratory for Molecular Sciences, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China.

In this work, a new series of chemical isotope labeling reagents, levofloxacin-hydrazide-based mass tags (LHMTs) named as LHMT359/360/361/362/363/364/365/366/373/375/376/378/379/381 were first designed and synthesized for the high-throughput analysis of potential biomarkers containing hexanal and heptanal of lung cancer. We exploited a new core structure of levofloxacin-, which significantly enhanced the multiplexing capability. Among them, LHMT359 was used for labeling standard compounds as internal standards for quantification. Using LHMT373-heptanal as dummy template, dummy magnetic molecularly imprinted polymers (DMMIPs) were prepared for magnetic dispersive solid-phase extraction after derivatization procedure. Other 12 LHMTs were established for high-throughput labeling hexanal and heptanal in human serum samples. The presynthesized DMMIPs can selectively extract LHMTs-derivatives of hexanal and heptanal from equally mixed derivatization solutions. The enriched derivatives of hexanal and heptanal were quantified by ultrahigh-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). A single UHPLC-MS/MS run enabled simultaneously quantifying hexanal and heptanal from 12 serum samples only within 2 min. The limits of detection were all 0.5 pM for hexanal and heptanal. The accuracies from human serum samples ranged from -10.2% to +11.0% with the intra- and interday precisions less than 11.3%. Meanwhile, this method was successfully applied for the analysis of hexanal and heptanal in serum samples from healthy people and lung cancer patients. The results show that this method has the significant advantages of high sensitivity, accuracy, selectivity, and analysis-throughput. The method application indicates that the developed method is promising in the screening of suspected lung cancer patients.
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http://dx.doi.org/10.1021/jasms.0c00222DOI Listing
September 2020

Insights into the Mo-Doping Effect on the Electrocatalytic Performance of Hierarchical CoMoS Nanosheet Arrays for Hydrogen Generation and Urea Oxidation.

ACS Appl Mater Interfaces 2020 Sep 25;12(36):40194-40203. Epub 2020 Aug 25.

State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China.

Energy-efficient, low-cost, and highly durable catalysts for the electrochemical hydrogen evolution reaction (HER) and urea oxidation reaction (UOR) are extremely important for related sustainable energy systems. In the present work, hierarchical coassembled cobalt molybdenum sulfide nanosheets deposited on carbon cloth (CC) were synthesized as catalysts for hydrogen evolution and urea oxidation. By adjusting the doping amount of Mo, 2D nanosheets with different morphologies and compositions (CoMoS-CC) can be obtained. The as-prepared nanosheet materials with abundant active sites exhibit superior properties on the electrochemical HER and UOR in alkaline medium. Significantly, the Mo-doping concentration and composition of the formed nanosheets have large effects on the electrocatalytic activity. The fabricated nanosheets with optimal Mo doping (CoMoS-CC) illustrate the best catalytic properties for the HER in N-saturated 1.0 M KOH. A small overpotential (85 mV) is needed to meet the current density of 10 mA/cm. This study indicates that the doping of an appropriate amount of molybdenum into CoS nanosheets can efficiently improve the catalytic performance. Also, the nanosheet catalyst exhibits an extremely high electrocatalytic activity for the UOR, and the electrochemical results indicate that a relatively low cell voltage of 1.50 V is needed to obtain the current density of 10 mA/cm. The present work demonstrates the potential application of CoMoS nanosheets in the energy electrocatalysis area and the insights into performance-boosting through heteroatom doping and optimization of the composition and structure.
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http://dx.doi.org/10.1021/acsami.0c06716DOI Listing
September 2020

Derivatization-based magnetic dummy molecularly imprinted polymers integrated with 4-plex stable isotope labeling derivatization strategy for specific and rapid determination of L-hydroxyproline in human serum.

Anal Chim Acta 2020 Aug 6;1127:57-68. Epub 2020 Jul 6.

Beijing National Laboratory for Molecular Sciences, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, PR China.

The specific determination of L-hydroxyproline (Hyp) can serve as a potential indicator for early clinical diagnosis of liver fibrosis. In this work, an integrated strategy based on 4-plex stable isotope labeling derivatization combined with dummy magnetic molecularly imprinted polymers (QSILD-DMMIPs) was developed for specific extraction and rapid determination of Hyp in human serum by ultra high performance liquid chromatography tandem mass spectrometry. A new series of QSILD reagents d/d/d/d-6-N-methyl-rhodamine 6G-N-hydroxysuccinimidyl formate (d/d/d/d-MRSF) were designed, synthesized and applied for the high-throughput labeling of Hyp in serum samples. The structural analogue derivative of Hyp with 6-N-ethyl-rhodamine 6G-N-hydroxysuccinimidyl formate (ERSF-Hyp) was synthesized and used as a novel dummy template to prepare DMMIPs. The DMMIPs were well characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), fourier transform infrared spectroscopy (FTIR), Brunner Emmet Teller (BET) measurements, thermogravimetric analysis (TGA), X-ray diffraction (XRD), zeta potential and adsorption experiments. All d/d/d/d-MRSF-Hyp derivatives were conveniently and specifically adsorbed by DMMIPs in magnetic dispersive solid phase extraction procedure before injection. Method validation results including linearity (0.2-100 ng mL), limits of detection and quantitation (0.05 and 0.2 ng mL), accuracy, precision, stability, matrix effect and derivatization efficiency were satisfactory. The analytical performances benefited from efficient integration of QSILD and specific DMMIPs extraction. The proposed strategy was successfully applied for Hyp determination in human serum of liver fibrosis patients and healthy controls, which was of great significance to early diagnosis.
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http://dx.doi.org/10.1016/j.aca.2020.06.045DOI Listing
August 2020

8-Plex stable isotope labeling absolute quantitation strategy combined with dual-targeted recognizing function material for simultaneous separation and determination of glucosylsphingosine and galactosylsphingosine in human plasma.

Anal Chim Acta 2020 Aug 16;1124:40-51. Epub 2020 May 16.

Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, PR China.

Glucosylsphingosine (GlcS) in plasma is considered to be a reliable biomarker of Gaucher disease. The detection difficulty of GlcS is that it is difficult to achieve simultaneous separation and quantification with its isomer galactosylsphingosine (GalS), a biomarker of Krabbe disease. In this work, a multiplexed stable isotope labeling absolute quantization strategy coupled with magnetic dispersive solid phase extraction using new prepared dummy magnetic molecularly imprinted polymers (DMMIPs) has been developed for this purpose by ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). 8-Plex Amine-reactive Mass Difference Tags (M360/361/362/363/373/375/376/378-AMDTs), were designed, synthesized and used to label GalS and GlcS in different 8 plasma samples, respectively. Synchronously, M359-AMDTs was prepared and used to label mixed standards of GalS and GlcS, which served as internal standards in UHPLC-MS/MS quantitation. Then DMMIPs possessing dual recognition function were applied for specific enrichment and purification of all GlcS and GalS derivatives from a combined solution of labeled 8-plex plasma samples and mixed standards before UHPLC-MS/MS injection. The labeling efficiency, chromatographic retention and mass spectrometry responses of all the 9 AMDTs reagents were consistent for GlcS and GalS. The established and validated method enabled 8-plex plasma samples quantification in a single UHPLC-MS/MS run (<2.0 min). Good linearity of AMDTs-GlcS/GalS derivatives was obtained in the range of 0.02-800 nM. LODs of GlcS and GalS were both 0.005 nM. The recoveries were in the range of 96.1-107.2%. The method was successfully applied for multiplex quantitative analysis of GlcS and GalS in human plasma samples. The results indicated that this method was capable of better realizing the simultaneous separation and quantification of GalS and GlcS compared to reported methods.
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http://dx.doi.org/10.1016/j.aca.2020.05.032DOI Listing
August 2020

9-Plex ultra high performance liquid chromatography tandem mass spectrometry determination of free hydroxyl polycyclic aromatic hydrocarbons in human plasma and urine.

J Chromatogr A 2020 Jul 6;1623:461182. Epub 2020 May 6.

Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, PR China.

Hydroxyl-polycyclic aromatic hydrocarbons (OH-PAHs) are biomarkers for assessing the exposure levels of polycyclic aromatic hydrocarbons (PAHs). A series of stable isotope mass tags (SIMT-332/338/346/349/351/354/360/363/374/377) were firstly designed and synthesized to perform multiplexed stable isotope labeling derivatization (MSILD) of OH-PAHs in human plasma and urine. Their derivatives were enriched and purified by magnetic dispersive solid phase extraction (MDSPE) using prepared FeO/GO and then determined by ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) in multiple reaction monitoring mode. 9-Plexed MSILD reagents were prepared using pipemidic acid as core structure with different isotope mass tags, in which carbonyl chloride group was used to label OH-PAHs. The SIMT-346 labeled OH-PAHs standards were used as internal standards, which can greatly increase the quantitative accuracy. 9-Plex labeled nine different real samples can be quantified by UHPLC-MS/MS in a single run. Under optimized MSILD-MDSPE conditions, good linearities of seven OH-PAHs were obtained with satisfactory coefficient of determination R > 0.991. Limits of detection (LODs) of seven OH-PAHs were from 0.1 to 0.5 pg/mL, and limits of quantitation (LOQs) ranged from 0.5 to 2.0 pg/mL. The intra- and inter-day precisions ranged in 2.3-12.4% with accuracies in the range of 91.7-108.4%. Acceptable results of matrix effect (89.7-105.7%) and derivatization efficiency (> 96.4%) were obtained. In short, the developed method has been proved to be high-throughput, sensitive, accurate and easy-handling. This method was applied for the measurement of seven free OH-PAHs in human urine and plasma, and expected to provide technical support for the evaluation of PAHs exposure levels in humans.
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http://dx.doi.org/10.1016/j.chroma.2020.461182DOI Listing
July 2020

Multiplexed derivatization strategy-based dummy molecularly imprinted polymers as sorbents for magnetic dispersive solid phase extraction of globotriaosylsphingosine prior to UHPLC-MS/MS quantitation.

Mikrochim Acta 2020 06 5;187(7):373. Epub 2020 Jun 5.

Beijing National Laboratory for Molecular Sciences, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, People's Republic of China.

A new series of 9-plex chemical isotope-labeling reagents, levofloxacin-based mass tags (LMTs) named as LMT359, 360, 361, 362, 363, 373, 375, 376, and 378, was firstly designed and synthesized for the high-throughput labeling of globotriaosylsphingosine (lyso-Gb3), a disease biomarker of Fabry disease. Creatively based on derivatization strategy-dummy template technique, dummy magnetic molecularly imprinted polymers (DMMIPs) were designed and prepared using LMT387-labeled lyso-Gb3 as a dummy template. The novel DMMIP material was used as sorbents for magnetic dispersive solid-phase extraction of 9-plexed LMT derivatives of lyso-Gb3 from equally mixed derivatization solutions. The enriched 8-plexed lyso-Gb3 derivatives from 8 real samples were quantified by ultra-high-performance liquid chromatography tandem mass spectrometry in a single run using simultaneously extracted LMT359-labeled standard lyso-Gb3 as internal standards. DMMIPs were characterized by using the transmission electron microscope (TEM), Fourier transform infrared, X-ray photoelectron spectroscopy, and some other characterization techniques. TEM micrograph showed that the prepared DMMIPs had an apparent imprinting layer. Triple-recognition abilities of DMMIPs towards LMT-lyso-Gb3 mainly rely on the hydrogen bonding, electrostatic attraction, hydrophobic interaction, and boronate affinity. The imprinting factor of DMMIPs towards LMT-lyso-Gb3 was 5.1. This method shows the advantages of high selectivity (triple recognition), high sensitivity, high accuracy (recovery 93.5-108.8%), and high throughput (8 samples in a single run). The proposed method was successfully applied to the determination of lyso-Gb3 in plasma samples with spiked recoveries in the range of 95.0-102.4%. This indicates that the method is promising in bioanalysis and medical testing of lyso-Gb3 in the future. Graphical abstract Synthesis of multiplexed derivatization reagents and its correlative molecularly imprinted polymers for magnetic extraction of globotriaosylsphingosine.
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http://dx.doi.org/10.1007/s00604-020-04341-4DOI Listing
June 2020

Synchronous measuring of triptolide changes in rat brain and blood and its application to a comparative pharmacokinetic study in normal and Alzheimer's disease rats.

J Pharm Biomed Anal 2020 Jun 17;185:113263. Epub 2020 Mar 17.

Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.

Triptolide, a major active ingredient of Tripterygium wilfordii Hook F, provides anti-inflammatory and neuroprotective activities. In this study, a microwave-assisted stable isotope labeling derivatization-magnetic dispersive solid phase extraction (MA-SILD-MDSPE) combined with ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method has been developed for the determination of the triptolide in rat microdialysates. A pair of SILD reagents (d-/d-3-N-methyl-2'-carboxyl Rhodamine 6G, d-/d-MCR6G) were used to label triptolide in real samples and standards under mild conditions. The introduction of SILD reagents enhanced the sensitivity of MS/MS detection and ensured accurate quantification. A novel molecularly imprinted polymer coating with d-MCR6G labeled triptolide as template was firstly synthesized by precipitation polymerization method, and used to selectively extract the labeled triptolides from complex matrices. The purified d-/d-MCR6G-triptolides were determined by UHPLC-MS/MS analysis. Using the proposed method, a good linearity (R>0.995), low limits of detection (LOD, 0.45-0.50 pg/mL) and quantification (LOQ, 3.0 pg/mL) were achieved. The intra- and inter-day precision and accuracy were within the acceptable ranges. No significant matrix effect was observed. The derivatization efficiency was more than 96 %. The validated method was successfully applied to a comparative pharmacokinetic study of triptolide synchronously in brain and blood of normal and Alzheimer's disease rats by in vivo microdialysis sampling technique.
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http://dx.doi.org/10.1016/j.jpba.2020.113263DOI Listing
June 2020

Recent progresses of derivatization approaches in the targeted lipidomics analysis by mass spectrometry.

J Sep Sci 2020 May 28;43(9-10):1838-1846. Epub 2020 Feb 28.

Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, P.R. China.

Lipidomics plays an essential role in the development of an improved understanding of lipids metabolism and the identification of new biomarkers or therapeutic targets of related diseases. The strong analytical power of mass spectrometry and its rapid developments in the respect of instruments and techniques have significantly accelerated the emerging lipidomics and related application fields in biology, medicine, and pharmacy. The strategy of chemical derivatization can remarkably improve the shortcomings of mass spectrometric analytical technologies of shotgun lipidomics and liquid chromatography mass spectrometry, and in the past decade many related studies have been reported for fatty acids, glycerophospholipids, sphingomyelins, monoglycerides, diacylglycerols, long-chain bases, steroids, and so on. Therefore, this review will focus on new chemical derivatization approaches about the research progresses of shotgun-based and liquid chromatography mass spectrometry-based targeted lipidomics (from 2005 to July 2019, most of reports emerged in the past 5 years), and put forward the problems and prospects in this field. It is expected to be helpful for the design and synthesis of new derivatization reagents, especially the outstanding stable isotope labeling derivatization reagents, and the development and application of new chemical derivatization strategies and matched mass spectrometric analysis methods.
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http://dx.doi.org/10.1002/jssc.201901346DOI Listing
May 2020

Synthesis of porous CoS for enhanced voltammetric nonenzymatic determination of glucose.

Mikrochim Acta 2020 01 6;187(1):98. Epub 2020 Jan 6.

Shandong Province Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China.

Porous CoS was synthesized by a two-step hydrothermal method, and its morphology and structure were characterized by transmission electron microscopy and X-ray diffraction. Electrochemical investigations showed that a glassy carbon electrode modified with CoS exhibits high electrocatalytic activity toward glucose in 0.2 M NaOH solution. Figures of merit for this sensor include (i) a wide linear range (2.0 μM to 1.1 mM), (ii) a working potential near 0.52 V (vs. Ag/AgCl), (iii) high sensitivity (346.7 μA mM cm), and (iv) a 0.17 μM detection limit. Graphical abstractPorous CoS was explored as electrocatalyst for glucose oxidation. It exhibits distinctly higher electrocatalytic activity toward glucose oxidation than CoO.
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http://dx.doi.org/10.1007/s00604-019-4079-0DOI Listing
January 2020

Quadruplex stable isotope derivatization strategy for the determination of panaxadiol and panaxatriol in foodstuffs and medicinal materials using ultra high performance liquid chromatography tandem mass spectrometry.

J Chromatogr A 2020 Apr 16;1616:460794. Epub 2019 Dec 16.

Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, PR China.

This work proposed a novel strategy based on quadruplex stable isotope derivatization for sensitive, accurate, speedy and green determination of panaxadiol (PD) and panaxatriol (PT). This strategy integrated with ultrasound-assisted dispersive liquid-liquid microextraction, microwave-assisted derivatization, and magnetic graphene oxide dispersive solid phase extraction as efficient sample pretreatment techniques, coupling with ultra-high performance liquid chromatography tandem mass spectrometry detection in multiple reaction monitoring mode for the analytical purpose of high-throughput, sensitivity, selectivity, green and accuracy. Quadruplex mass spectrometry sensitizing derivatization reagents, 3-N-(D-/D-methyl-, and D-/D-ethyl-)-2'-carboxyl chloride rhodamine 6 G, were designed, synthesized and applied for the high-throughput derivatization of hydroxyl‑containing PD and PT for the first time. The analogue derivatives of PD and PT standards using 3-N-propyl-2'-carboxyl chloride rhodamine 6 G as derivatization reagent were employed as the internal standards for the mass spectrometry quantitation to minimize matrix effect. All rhodamine 6 G derivatives of PD and PT were easily and selectively adsorbed by magnetic graphene oxide for efficient magnetic dispersive solid phase extraction before injection. Parameters of (micro-) extractions, derivatization and liquid chromatography-mass spectrometry conditions were all optimized in details. Method validation results consisting of linearity, accuracy, precision, repeatability, matrix effect, stability and limits of detection (LODs, 0.02 ng/mL for PD and 0.03 ng/mL for PT) were determined. The analytical performance of this method benefited from efficient integration of suitable sample pretreatment techniques and characteristic structure of rhodamine 6 G with four mass tags in derivatization reagents. The developed and validated method has been applied to the quantitation of PD and PT for the quality assessment of related foodstuffs and traditional Chinese medicinal materials.
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http://dx.doi.org/10.1016/j.chroma.2019.460794DOI Listing
April 2020

Colorimetric determination of the activities of tyrosinase and catalase via substrate-triggered decomposition of MnO nanosheets.

Mikrochim Acta 2019 11 27;186(12):848. Epub 2019 Nov 27.

College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu City, 273165, Shandong Province, China.

The authors describe novel colorimetric assays for tyrosinase (TYR) and catalase (CAT) based on the substrate-triggered decomposition of MnO nanosheets (NSs). The MnO NSs can act as oxidase mimics that catalyze the oxidation of the substrate tetramethylbenzidine (TMB) to form a blue dye with an absorption maximum at 652 nm. The oxidase-mimicking activity of the MnO NSs is inhibited by dopamine (DA)/hydrogen peroxide (HO) due to their decomposition of the MnO NSs. TYR catalyzes the oxidation of DA while CAT can decompose HO into water and oxygen. Therefore, the oxidase-mimicking activity of MnO NSs is restored in the presence of both enzymes and their substrates. Based on the competitive consumption of substrates between enzymes and MnO NSs, a colorimetric method for determination of enzyme activity and its substrate is developed. The detection limits for TYR and CAT are 6 mU·mL and 33 mU·mL, respectively. Graphical abstractA colorimetric method for monitoring enzyme activity and its substrate is described. It is based on the substrate-inhibited oxidase-mimicking activity of MnO nanosheets.
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http://dx.doi.org/10.1007/s00604-019-3995-3DOI Listing
November 2019

Turn-on fluorescent assay for antioxidants based on their inhibiting polymerization of dopamine on graphene quantum dots.

Spectrochim Acta A Mol Biomol Spectrosc 2020 Jan 6;225:117516. Epub 2019 Sep 6.

College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu City, Shandong Province 273165, China.

We describe a sensitive turn-on fluorescent assay for antioxidants by using fluorescence-tunable graphene quantum dots (GQDs). GQDs exhibited strong fluorescence without dopamine (DA). DA could self-polymerize to a thin polydopamine (PDA) film on the surface of GQDs under alkaline environment, resulting in the fluorescence quenching of GQDs via fluorescence resonance energy transfer (FRET). However, the self-polymerization of DA could be effectively inhibited in the presence of antioxidants including glutathione (GSH), ascorbic acid (AA), cysteine (Cys), and homocysteine (Hcys). Thus, the fluorescence of GQDs restored. The "turn-on" sensing of antioxidants could be achieved with high sensitivity. The detection limit for GSH, AA, Cys, and Hcys could be achieved as low as 2.4 nM, 1.5 nM, 4.2 nM, and 4.4 nM, respectively. Finally, the GQDs@PDA system was applied for monitoring cerebral antioxidants in rat brain microdialysates. This work promises new opportunities to evaluate antioxidant capacity in physiological and pathological fields.
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http://dx.doi.org/10.1016/j.saa.2019.117516DOI Listing
January 2020

SET nuclear proto-oncogene gene expression is associated with microsatellite instability in human colorectal cancer identified by co-expression analysis.

Dig Liver Dis 2020 03 6;52(3):339-346. Epub 2019 Sep 6.

Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, China; Hubei Clinical Center and Key Lab of Intestinal and Colorectal Diseases, Wuhan, China. Electronic address:

Backgrounds And Aims: Microsatellite instability (MSI) is one of the promising biomarkers in human colorectal cancers (CRCs), and it is influenced by an intricate gene interaction network. Hence, we aimed to identify and validate hub genes associated with MSI CRC and to illustrate its underlying mechanisms.

Methods: Weighted gene co-expression network analysis (WGCNA) was used to investigate potential regulatory targets and relationships between key modules and hub genes associated with MSI CRC.

Results: In the red module (r = 0.83), SET nuclear proto-oncogene (SET) was selected due to its high intra-modular connectivity and module membership. In the test sets, SET expression was downregulated in MSI CRCs compared to that in microsatellite stability (MSS) CRCs. SET expression level had a good performance in stratifying patients into MSI or MSS CRCs (area under the curve = 0.953). Moreover, the BRAF V600E mutation was highly associated with SET expression, and MSI/HLA- samples showed lower levels of SET mRNA expression than MSS/HLA- samples. Finally, gene set enrichment analysis (GSEA) indicated that patients in the SET low expression group were enriched in base excision repair.

Conclusion: SET was identified and validated as a novel potential biomarker in MSI CRCs, and SET probably acts through regulating the base excision repair pathway.
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http://dx.doi.org/10.1016/j.dld.2019.07.020DOI Listing
March 2020

Hypoglycemic effects of wheat bran alkyresorcinols in high-fat/high-sucrose diet and low-dose streptozotocin-induced type 2 diabetic male mice and protection of pancreatic β cells.

Food Funct 2019 Jun;10(6):3282-3290

College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212018, China.

In the present study, the hypoglycemic effects of wheat bran alkyresorcinols (ARs) were investigated in type 2 diabetes mellitus (T2DM) mice induced by a high-fat/high-sucrose diet (HFSD) combined with low dose streptozotocin (STZ). After the consumption of 5 mg kg-1 d-1 acarbose (positive control) and different doses of wheat bran ARs (50, 200 and 500 mg kg-1 d-1) for 4 weeks, the fasting blood glucose (FBG) levels in T2DM mice were found to be reduced significantly (p < 0.05), and the effects of 200 and 500 mg kg-1 d-1 administration were better than that of 50 mg kg-1 d-1. The results of the oral glucose tolerance test (OGTT) also showed that both acarbose and AR administration significantly increased the glucose tolerance of the T2DM mice. Then, the fasting serum insulin levels (FINS) were significantly reduced by AR treatment, and the effect of 500 mg kg-1 d-1 AR administration was better than that of 5 mg kg-1 d-1 acarbose. The profile of plasma lipids was analyzed simultaneously, and the results showed that the contents of total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) were significantly decreased, while the content of high-density lipoprotein cholesterol (HDL-C) was increased significantly after 200 and 500 mg kg-1 d-1 AR treatment (p < 0.05). Furthermore, 200 and 500 mg kg-1 d-1 ARs significantly increased the content of hepatic glycogen and the activity of glucokinase (p < 0.01) in T2DM mice. The relative mRNA levels of glucose transporter 2 (GLUT2) in the liver tissue were increased markedly in 200 and 500 mg kg-1 d-1 AR treatment groups (p < 0.01), and the relative mRNA levels of glucose transporter 4 (GLUT4) in the epididymal adipose tissue were increased significantly in all AR treatment groups, especially significantly higher than acarbose (p < 0.01). Histological analyses revealed that treatment with ARs exerted a protective role on pancreatic β-cells. The results indicated that ARs could be an effective hypoglycemic active ingredient in whole grain diets.
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http://dx.doi.org/10.1039/c8fo02396dDOI Listing
June 2019

A novel and sensitive fluorescent assay for artemisinin with graphene quantum dots based on inner filter effect.

Talanta 2019 Aug 14;200:163-168. Epub 2019 Mar 14.

Shandong Key Laboratory of TCM Quality Control Technology, Shandong Analysis and Test Center, Qilu University of Technology (Shandong Academy of Sciences), 19 Keyuan Street, Jinan 250014, China.

The authors describe a novel method for the determination of artemisinin (ART) by using graphene quantum dots (GQDs) as the fluorescent probes. This method is based on the fact that ART can react with p-aminophenylboronic acid (p-ABA) to produce p-aminophenol (p-AP). While in the presence of tyrosinase (TYR), p-AP can be oxidized into 4-amino-1,2-benzoquinone, which effectively quenched the fluorescence of GQDs due to the inner filter effect (IFE). By making use of these reactions, a novel and sensitive fluorescent assay for ART has been developed. The calibration curve for the determination of ART is linear in the range of 0.1-5 μM and 5-55 μM with the detection limit of 33 nM, which is more sensitive than most of other methods. Some common coexisting substances including Ca, Na, Mg, K, PO, starch, lactose, dextrin, and magnesium stearat have negligible effects on the fluorescence intensity of GQDs-TYR-p-ABA system. Finally, the sensing system was successfully applied to the detection of the compound naphthoquine phosphate tablet samples with satisfactory recoveries. This IFE-based GQDs fluorescence sensing strategy is facile and sensitive for the determination of ART because neither the surface modification nor the linking between the receptor and the fluorophore is required.
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http://dx.doi.org/10.1016/j.talanta.2019.03.058DOI Listing
August 2019

Integration of stable isotope labeling derivatization and magnetic dispersive solid phase extraction for measurement of neurosteroids by in vivo microdialysis and UHPLC-MS/MS.

Talanta 2019 Jul 10;199:97-106. Epub 2019 Feb 10.

Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.

In this work, a novel strategy of stable isotope labeling derivatization (SILD) combined with magnetic dispersive solid-phase extraction (MDSPE), has been proposed for simultaneous monitoring of neurosteroids changes linked to Parkinson's disease (PD) by in vivo microdialysis. The developed method was based on ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) detection using multiple-reaction monitoring (MRM) mode. In this study, a new pair of stable isotope labeling reagents d-/d-3-N-methyl-2'-carboxyl Rhodamine 6G (d-/d-MCR6G), were designed and synthesized for derivatizing neurosteroids in rat blood microdialysates and neurosteroid standards, respectively. d-MCR6G labeled neurosteroids standards were used as internal standard for the following pretreatment and UHPLC-MS/MS quantification to minimize the deviations caused by complex matrix and ion suppression effects in mass spectrometry analysis. Under the optimized derivatization and extraction conditions, good linearities of eight neurosteroids were obtained with correlation coefficients R values > 0.98. The limits of detection (LODs) and quantitation (LOQs) ranged from 0.06 to 0.12 pg/mL and 0.30-0.40 pg/mL, respectively. Taken together, the established method exhibited high sensitivity and selectivity, excellent accuracy, convenience and high efficiency. It was applied for the simultaneous and dynamic measurement of multiple neurosteroids in normal and PD rat blood microdialysates. This method would be expected to be potentially useful for the monitoring and drug treatment of PD and related neurological disorders in the future.
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http://dx.doi.org/10.1016/j.talanta.2019.02.011DOI Listing
July 2019

Stable isotope labeling derivatization coupled with magnetic dispersive solid phase extraction for the determination of hydroxyl-containing cholesterol and metabolites by in vivo microdialysis and ultra-high performance liquid chromatography tandem mass spectrometry.

J Chromatogr A 2019 Jun 14;1594:23-33. Epub 2019 Feb 14.

Shandong Key Laboratory of TCM Quality Control Technology, Shandong Analysis and Test Center, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250014, Shandong, PR China. Electronic address:

Hydroxyl-containing cholesterol and metabolites (HCMs) are potential biomarkers for Alzheimer's disease. Therefore, quantitative analysis of HCMs can serve as an indicator of clinical diagnosis and drug treatment. In this work, we developed an accurate, sensitive and rapid method for the determination of HCMs in rat blood microdialysates by microwave-assisted stable isotope labeling derivatization (MA-SILD) magnetic dispersive solid phase extraction (MDSPE) coupled with ultra-high performance liquid chromatography electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS) in the multiple reaction monitoring mode (MRM). In this respect, a pair of new SILD reagents, d-/d-3-N-methyl-2'-carboxyl Rhodamine 6G (d-/d-MCR6G), were designed, synthesized and used to label HCMs. Rhodamine 6G with permanently positive charge was introduced into HCMs, improving ionization efficiency and enhancing detection sensitivity. In addition, the d-MCR6G labeled standards were served as internal standards, reducing the matrix effect and guaranteeing accurate quantification. Various factors affecting MA-SILD and MDSPE were optimized. Furthermore, good linearity was obtained with R > 0.994 over the concentration range of 2-3000 pg/mL. The limits of detection (LODs) and quantitation (LOQs) were in the range of 0.24-0.31 and 1.5-1.8 pg/mL, respectively. Acceptable precision (1.6-12.6%), accuracy (87.9-105.2%), matrix effect (85.4-111.2%) and derivatization efficiency (>98%) were achieved. On the whole, this method was validated and applied to accurate, sensitive and simple quantitation of HCMs in rat blood microdialysates. This work would provide some technical support in the diagnosis and treatment of AD or other neurological diseases.
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http://dx.doi.org/10.1016/j.chroma.2019.02.021DOI Listing
June 2019

Fluorescence Immunoassay Based on the Alkaline Phosphatase Triggered in Situ Fluorogenic Reaction of o-Phenylenediamine and Ascorbic Acid.

Anal Chem 2019 02 7;91(4):2978-2984. Epub 2019 Feb 7.

State Key Laboratory of Electroanalytical Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun , Jilin 130012 , China.

Inspired by the special reducing capability of ascorbic acid (AA), ascorbic acid 2-phosphate (AA2P) has been extensively utilized as a substrate in current alkaline phosphatase (ALP) activity assays owing to the ALP-triggered transformation of AA2P into AA. However, such assays usually require AA-related complicated and laborious synthesis and/or signal generation procedures. Herein, we report an interesting in situ fluorogenic interaction between o-phenylenediamine (OPD) and AA, which inspires us to put forward a novel and simple AA2P/OPD-participated fluorescence turn-on ALP activity assay for the first time, and then the corresponding ALP-based fluorescence enzyme-linked immunosorbent assay (ELISA) has also been developed by means of the conventional ELISA platforms. According to the convenient and facile detection process with clear response mechanism, our fluorogenic reaction-based assay exhibits good sensitivity, selectivity, and excellent sensing performance, which ensures fluorescence ELISA to potentially be applied in clinical diagnosis by employing a well-studied biomarker of hepatocellular carcinoma, α-fetoprotein (AFP) as the model analyte. Such original ELISA via in situ formation of fluorophore from scratch gives a new sight to develop other potential immunoassay platforms in early clinical diagnosis by controlling the target antigens in the near future.
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http://dx.doi.org/10.1021/acs.analchem.8b05203DOI Listing
February 2019

Stable isotope labeling derivatization and magnetic dispersive solid phase extraction coupled with UHPLC-MS/MS for the measurement of brain neurotransmitters in post-stroke depression rats administrated with gastrodin.

Anal Chim Acta 2019 Mar 9;1051:73-81. Epub 2018 Nov 9.

Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China. Electronic address:

Synchronous measurement of brain neurotransmitters and blood drug metabolism by dual sites in vivo microdialysis can provide very important information for several neurological disorders such as post-stroke depression (PSD). In this work, d/d-6-N-methyl-rhodamine 6G-N-hydroxysuccinimidyl formate (d/d-MRSF) were firstly designed, synthesized and used as stable isotope labeling derivatization reagents for the determination of multiple neurotransmitters by ultra-high performance liquid chromatography-tandem mass spectrometry. The light d-MRSF was used to label neurotransmitters in real samples and the heavy d-MRSF was used to label standards, which served as internal standards for quantification to minimize matrix effect. The d/d-MRSF-neurotransmitter derivatives were easily adsorbed onto the surface of FeO@graphene oxide. Magnetic dispersive solid phase extraction followed with stable isotope labeling derivatization was developed for efficient sample pretreatment. The permanent positively charged moiety of d/d-MRSF significantly enhanced the ionization efficiency of neurotransmitters. The comparison results indicated that the synthesized MRSF derivatization method can bring better detection sensitivity than the commercial dansyl chloride method about tens to hundreds of times on the same instrumentation. Specific and regular product ions of m/z 413.3 and 416.3, m/z 429.4 and 432.4 were observed for d-and d-MRSF labeled neurotransmitters, respectively. The limits of detection were in the range of 2.0-40.0 pM. The accuracies ranged from 92.3% to 108.2% with the intra- and inter-day precisions in the range of 2.2-12.8%. Synchronous and dynamic determination of concentrations changes of brain neurotransmitters and blood gastrodin of PSD rats was achieved. The results indicated that gastrodin had analogous regulating effect of brain neurotransmitter, which like the clinical medicine fluoxetine of PSD. Taken together, the developed method was demonstrated to be promising for sensitive, accurate and simultaneous determination of multiple neurotransmitters in trace biofluids.
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http://dx.doi.org/10.1016/j.aca.2018.11.011DOI Listing
March 2019

Molecular beacon-templated silver nanoclusters as a fluorescent probe for determination of bleomycin via DNA scission.

Mikrochim Acta 2018 08 6;185(9):403. Epub 2018 Aug 6.

College of Chemistry and Chemical Engineering, Qufu Normal University, City, Shandong Province, Qufu, 273165, China.

The authors describe a molecular beacon-based fluorescent probe for the determination of the cancer drug bleomycin (BLM). The probe was tagged with DNA-templated silver nanoclusters (DNA-AgNCs) and guanine-rich sequences (GRSs) at two terminals serving as signal reporter with a loop. In the absence of the BLM-iron(II) complex [BLM-Fe(II)], the probe has a hairpin shape and displays strong fluorescence because the AgNCs are close to the GRSs. In the presence of the BLM-Fe(II) complex, it will selectively cleave the probe at the 5'-GC-3' scission site of the loop. This displaces the AgNCs away from the GRSs and causes a decrease in fluorescence, best measured at excitation/emission wavelengths of 565/623 nm. This effect enables BLM to be detected with a detection limit as low as 33 pM, which was 1-3 orders of magnitude more sensitive than most of the previous reports. The probe was applied for the determination of BLM in spiked human serum samples, and excellent performance was achieved. In our perception, the method described here represents a promising tool for highly sensitive and specific analysis of BLM during cancer treatment. Graphical abstract Schematic of a highly sensitive fluorometric assay forbleomycin. It is based on molecular beacon-templated silver nanoclusters and DNA scission.
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http://dx.doi.org/10.1007/s00604-018-2939-7DOI Listing
August 2018

Simultaneous Determination of Oleanolic Acid and Ursolic Acid by in Vivo Microdialysis via UHPLC-MS/MS Using Magnetic Dispersive Solid Phase Extraction Coupling with Microwave-Assisted Derivatization and Its Application to a Pharmacokinetic Study of Arctiumlappa L. Root Extract in Rats.

J Agric Food Chem 2018 Apr 23;66(15):3975-3982. Epub 2018 Mar 23.

Qinghai Provincial Key Laboratory of Tibetan Medicine Research & Key Laboratory of Tibetan Medicine Research , Northwest Institute of Plateau Biology, Chinese Academy of Science , Xining , Qinghai 810001 , P.R. China.

Simultaneous detection of oleanolic acid and ursolic acid in rat blood by in vivo microdialysis can provide important pharmacokinetics information. Microwave-assisted derivatization coupled with magnetic dispersive solid phase extraction was established for the determination of oleanolic acid and ursolic acid by liquid chromatography tandem mass spectrometry. 2'-Carbonyl-piperazine rhodamine B was first designed and synthesized as the derivatization reagent, which was easily adsorbed onto the surface of FeO/graphene oxide. Simultaneous derivatization and extraction of oleanolic acid and ursolic acid were performed on FeO/graphene oxide. The permanent positive charge of the derivatization reagent significantly improved the ionization efficiencies. The limits of detection were 0.025 and 0.020 ng/mL for oleanolic acid and ursolic acid, respectively. The validated method was shown to be promising for sensitive, accurate, and simultaneous determination of oleanolic acid and ursolic acid. It was used for their pharmacokinetics study in rat blood after oral administration of Arctiumlappa L. root extract.
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http://dx.doi.org/10.1021/acs.jafc.7b06015DOI Listing
April 2018

Al-Doped NiP nanosheet array: a superior and durable electrocatalyst for alkaline hydrogen evolution.

Chem Commun (Camb) 2018 Mar;54(23):2894-2897

College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.

It is highly desired to develop high-efficiency and low-cost catalysts for the hydrogen evolution reaction (HER). Herein, we report the development of an Al-doped NiP nanosheet array on Ti mesh as a high-performance and durable electrocatalyst for the HER in 1.0 M KOH. Such a catalyst demands an overpotential of 129 mV to afford 10 mA cm and maintains its catalytic activity for at least 20 h. This work offers us a promising cost-effective catalyst for large-scale electrolytic production of hydrogen fuels.
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http://dx.doi.org/10.1039/c7cc09445kDOI Listing
March 2018

Ni(OH)-FeP hybrid nanoarray for alkaline hydrogen evolution reaction with superior activity.

Chem Commun (Camb) 2018 Jan;54(10):1201-1204

College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.

It is highly attractive to develop efficient hydrogen evolution reaction (HER) electrocatalysts under alkaline conditions. In this communication, we report the preparation of amorphous Ni(OH) decorated FeP nanoarray on Ti mesh (Ni(OH)-FeP/TM) via electrodeposition. As a 3D electrode for the hydrogen evolution reaction, such Ni(OH)-FeP/TM demonstrates superior catalytic activity. Moreover, the as-prepares electrocatalyst requires an overpotential of only 76 mV to drive a current density of 10 mA cm, which is 94 mV less than that for FeP/TM. It also shows strong long-term electrochemical durability with its catalytic activity being maintained for at least 20 h.
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http://dx.doi.org/10.1039/c7cc07342aDOI Listing
January 2018

Polyhydric polymer-loaded pyrene composites as powerful adsorbents and fluorescent probes: highly efficient adsorption and test strips-based fluorimetric analysis of curcumin in urine and plant extracts.

Analyst 2018 Jan;143(2):392-395

Institute of Medicine and Materials Applied Technologies, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu City 273165, P. R. China.

Polyhydric poly (vinyl alcohol) was covalently loaded with a 1-pyrenecarboxyaldehyde fluorophore. The yielded PVA-Pyr composites can serve as powerful adsorbents and strong fluorescent probes for the highly efficient adsorption and sensitive fluorimetric detection with test strips of curcumin in samples of urine and plant extracts.
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http://dx.doi.org/10.1039/c7an01403aDOI Listing
January 2018

Core-shell magnetic molecularly imprinted polymers used rhodamine B hydroxyproline derivate as template combined with in situ derivatization for the specific measurement of L-hydroxyproline.

J Chromatogr A 2018 Jan 24;1532:30-39. Epub 2017 Nov 24.

Shandong Provincial Key Laboratory of Life-Organic Analysis & Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong, 273165, PR China; Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Chinese Academy of Science, Xining, Qinghai, 810001, PR China. Electronic address:

In this work, a novel core-shell magnetic molecularly imprinted polymers (MMIPs) for the measurement of L-Hydroxyproline (Hyp) in dairy products was prepared. The derivative of Hyp using N-hydroxysuccinimidyl rhodamine B ester (RBS) as derivatization reagent was employed as template to prepare RBS-Hyp-MMIPs (FeO@MIPs for RBS-Hyp). A new analytical procedure of in situ derivatization with MMIPs (ISD-MMIPs) has been developed for the specific extraction and determination of Hyp in dairy products by ultra high performance liquid chromatography tandem mass spectrometry. The RBS-Hyp-MMIPs was characterized by fourier transform infrared spectrometer and transmission electron microscopy, and evaluated by adsorption experiments. The adsorption process followed Langumuir adsorption isotherm with maximum adsorption capacity of RBS-Hyp on RBS-Hyp-MMIPs at 96 mg/g. In addition, RBS-Hyp-MMIPs showed a short equilibrium time (15.0 min), rapid magnetic separation (5 s) and high stability (retained 95.3% after six cycles). Under the optimized conditions, good linearity was observed with the limits of detection (S/N > 3) and limits of quantification (S/N > 10) at 0.1 and 0.5 ng/mL, respectively. On account of the specific extraction performance of RBS-Hyp-MMIPs, not any interference peak from real sample matrix was observed in the chromatograms of milk powder, liquid milk and milk drink. The proposed procedure was successfully applied for selective determination of Hyp from dairy products with satisfactory validation results, which is of great significance to food safety.
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http://dx.doi.org/10.1016/j.chroma.2017.11.053DOI Listing
January 2018