JOURNAL OF CHROMATOGRAPHY A
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2017
·
IF 3.981
Chusheng Liu,Haibin Li,Qiqin Wang,Jacques Crommen,Haibo Zhou,Zhengjin Jiang
The quest for higher column efficiency is one of the major research areas in polymer-based monolithic column fabrication. In this research, two novel polymer-based HILIC monolithic columns with 400 μm I.D. × 800 μm O.D. were prepared based on the thermally initiated co-polymerization of N,N -dimethyl- N -(3-methacrylamidopropyl)- N -(3-sulfopropyl) ammonium betaine (SPP) and ethylene glycol dimethacrylate (EDMA) or N,N’ -methylenebisacrylamide (MBA). In order to obtain a satisfactory performance in terms of column permeability, mechanical stability, efficiency and selectivity, the polymerization parameters were systematically optimized. Column efficiencies as high as 142, 000 plates/m and 120, 000 plates/m were observed for the analysis of neutral compounds at 0.6 mm/s on the poly(SPP- co -MBA) and poly(SPP- co -EDMA) monoliths, respectively. Furthermore, the Van Deemter plots for thiourea on the two monoliths were compared with that on a commercial silica based ZIC-HILIC column (3.5 μm, 200 Å, 150 mm × 300 μm I.D.) using ACN/H 2 O (90/10, v/v) as the mobile phase at room temperature. It was noticeable that the Van Deemter curves for both monoliths, particularly the poly(SPP- co -MBA) monolith, are significantly flatter than that obtained for the ZIC-HILIC column, which indicates that in spite of their larger internal diameters, they yield better overall efficiency, with less peak dispersion, across a much wider range of usable linear velocities. A clearly better separation performance was also observed for nucleobases, nucleosides, nucleotides and small peptides on the poly(SPP- co -MBA) monolith compared to the ZIC-HILIC column. It is particularly worth mentioning that these 400 μm I.D. polymer-based HILIC monolithic columns exhibit enhanced mechanical strength owing to the thicker capillary wall of the fused-silica capillaries.
研究领域:
分析化学
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色谱技术
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PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2014
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IF 4.258
Chusheng Liu,Weijia Chen,Guangxin Yuan,Yao Xiao,Jacques Crommen,Shihai Xu,Zhengjin Jiang
In order to investigate the effects of the crosslinker on the separation performance of polar zwitterionic sulfoalkylbetaine-type monolithic columns, three crosslinkers, i.e. 1,4-bis(acryloyl)piperazine (PDA), ethylene dimethacrylate (EDMA) and N , N ′-methylenebisacrylamide (MBA), were copolymerized with the hydrophilic monomer N , N -dimethyl- N -acryloyloxyethyl- N -(3-sulfopropyl)ammonium betaine (SPDA). The chromatographic properties of the three hydrophilic sulfoalkylbetaine-type monolithic columns, including column efficiency, permeability, porosity and separation mechanism, were systematically compared using scanning electron microscopy or micro-HPLC. Good selectivity in micro-HPLC separations was achieved on all three monolithic columns. The results indicate that the polarity of sulfoalkylbetaine-type monolithic columns may be related to the polarity of the crosslinker, which further affects column selectivity and efficiency. A particularly high column efficiency (100,000 plates/m) was obtained on the novel poly(SPDA- co -PDA) monolithic column at a linear velocity of 1 mm/s using thiourea as test analyte. A higher resolution was also observed for nucleobases, nucleosides and hydrophilic organic acids on this novel poly(SPDA- co -PDA) monolithic column compared to the other two columns.
研究领域:
分析化学
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色谱技术
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高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2019
·
IF 3.372
Haiyan Zhang,Chunjie Liu,Liang Chen,Bin Dai
We presented an improved preparation method to generate cryogels with controllable pore size. It included 5 stages: pre-cooling, pre-crystallization, crystal growth, freezing, and thawing (PPCFT); crystal growth was the key step. Chitosan (CS) cryogels with uniform and honeycomb-like structures were prepared with the method, and then the properties of these cryogels were studied. The results demonstrated that the mean pore diameters of CS cryogels were successfully controlled in a wide range (approximately 60–240 μm, by scanning electron microscope) by simply varying the temperature and time of crystal growth. The crystal growth law of this process was described by an empirical equation based on the classical theory for Ostwald ripening by Lifshitz, Slyozov, and Wagner (LSW). Furthermore, the hydrodynamics performance (permeability and column efficiency) of CS cryogel columns clearly varied with crystal growth conditions, while both the accessible porosity and water absorption ratio remained at a high level.
研究领域:
材料科学
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生物医学工程
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DOI
高影响因子
TALANTA
·
2014
·
IF 3.511
Qing Wang,Jing Li,Xin Yang,Li Xu,Zhi-guo Shi,Lan-Ying Xu
In the current study, zirconia (ZrO 2 ) and its composite, magnesia–zirconia (MgO–ZrO 2 ), were prepared as the hydrophilic interaction chromatographic (HILIC) stationary phases (SPs). Different experimental variables including water content, pH and buffer concentration in the mobile phase (MP) as well as column temperature were systematically studied to permit an in-depth understanding of the chromatographic properties of the mentioned SPs and to explore the retention mechanism further on. The results were compared with a native SiO 2 column. Adsorption was demonstrated as the main retention mechanism on the two ZrO 2 -based SPs. The transferring of the analytes from the MP to the ZrO 2 -based SPs was endothermic and high column temperature would facilitate the retention. In addition, the MgO–ZrO 2 SP exhibited superior resolution, column efficiency as well as stronger retention in comparison to the bare ZrO 2 SP, which demonstrated that the introduction of MgO could improve the structure and properties of the material. In conclusion, MgO–ZrO 2 was a promising material for HILIC applications.
研究领域:
分析化学
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材料科学
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PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
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2016
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IF 3.926
Jialiang Guo,Yuan Xiao,Yuanjing Lin,Jacques Crommen,Zhengjin Jiang
Low column efficiency for enantioseparations in capillary liquid chromatography (CLC) is a major problem commonly encountered with β -cyclodextrin ( β -CD) functionalized polymer-based monoliths. In order to investigate the effect of the crosslinker type on enantioseparation performance, three commonly used crosslinkers, i.e. 1,4-bis(acryloyl)piperazine (PDA), ethylene dimethacrylate (EDMA) and N , N -methylenebisacrylamide (MBA), were copolymerized using the one-pot approach with glycidyl methacrylate-mono-6-amino-6-deoxy- β -CD (GMA-NH 2 - β -CD) as functional monomer. The three monolithic columns, including poly(GMA-NH 2 - β -CD- co -PDA) and poly(GMA-NH 2 - β -CD- co -MBA), as well as the previously reported column poly(GMA-NH 2 - β -CD- co -EDMA) were systematically compared with respect to morphology, permeability, β -CD density, retention mechanism and efficiency. The enantioseparation ability of each column was evaluated using 14 chiral compounds, including mandelic acid derivatives, profens, N -derivatized amino acids, and herbicides, as test substances. The β -CD-functionalized monolith with MBA as crosslinker was found to exhibit higher polarity, higher column efficiency and better enantioseparation performance than those with PDA or EDMA as crosslinker.
研究领域:
分析化学
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色谱技术
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PubMed
高影响因子
TALANTA
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2017
·
IF 4.162
Xiao-jing Mao,Jing Li,Dan Liu,Ting Qiao,Liyun Ma,Xiao Sun,Li Xu,Zhi-guo Shi
The demand for fast chromatographic enantioseparation aroused the hot research in stationary phase matrix. In the present study, the flow-through silica, which is characterized by hierarchical pores of through pores in several hundred nanometer range and mesopores about 20 nm, was attempted for fast enantioseparation. Thanks to the large surface area and full openness of the through pores, the flow-through silica had comparable cellulose derivative loading amount as the commercial wide-pore silica, which was impracticable for most of the core-shell particles and sub-2-μm fully porous silica. In addition, the backpressure was about two times lower in the case of the flow-through silica of the same particle size to the commercial wide-pore silica, due to the highly porous structure of the former. Another appreciated merit of the flow-through silica in small size (~2 µm) was the less dependence of column efficiency on the flow rate . All of the above features rendered the flow-through silica a tremendous potential for fast enantioseparation with desired enantioselectivity , especially suitable for the polysaccharide chiral selector.
研究领域:
分析化学
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药物化学
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PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2025
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IF 4
Liang Lai,Hongying Lan,Hui Huang,Tong Li,Kesara Ar-sanork,Jia-Huan Qu,Dongsheng Xu,Zhengjin Jiang
In this study, the chromatographic performance of a novel dual-zwitterionic hydrophilic stationary phase were investigated. Three zwitterionic HILIC monoliths were prepared using 3-(4-((methacryloyloxy)methyl)-1-methylpiperidin-1-ium-1-yl)propane-1-sulfonate (MAMMPS), 2-methacryloyloxyethyl phosphorylcholine (MPC), and a combination of MAMMPS and MPC (1:1, molar ratio) with N,N' -methylenebisacrylamide (MBA), separately. The monoliths exhibited good repeatability and stability. A high column efficiency of 120,000 plates/m was reached on the novel dual-zwitterionic functionalized poly(MAMMPS@MPC- co -MBA) monolith. Through the analysis and testing with different standards, the poly(MAMMPS@MPC- co -MBA) monolith exhibited the strongest retention capacity for negatively charged benzoic acid derivatives due to its high hydrophilicity and weak electronegativity. In contrast, the poly(MPC- co -MBA) monolith, functionalized with a single zwitterion, facilitated electrostatic interactions with negatively charged analytes. Baseline separation was achieved on all three monoliths for selected nucleobases, nucleosides, phenol derivatives, and amine compounds. However, their retention strength was mainly related to the hydrophilicity of the stationary phases, while hydrogen bonding and electrostatic interactions played secondary roles. Among the monoliths, the poly(MAMMPS- co -MBA) monolith demonstrated the best separation for neutral, acidic, and alkaline compounds. These findings offer valuable insights for the future selection and application of dual-zwitterionic HILIC monoliths for chromatographic separations.
研究领域:
分析化学
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材料科学
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PubMed
高影响因子
Canadian Journal of Chemistry
·
2024
·Vol. 102
·期 9
·
IF 1.1
Yuanyuan Zhang,Mengyi Ba,Wen Li,Yanli Song,Xiang Xu,Haixin Liu,Wenxuan Zhao,Tao Sun,Zhiqiang Cai
Herein, we synthesized and used a novel pillar[5]arene with two functionalizable rims (AP5A-C10-OAc) as stationary phase in gas chromatography (GC). The AP5A-C10-OAc column (0.25 mm, i.d.) showed a high column efficiency of 4107 plates/m and medium polarity. The AP5A-C10-OAc stationary phase possesses unique amphiphilic structure, including a π-electron rich cavity and two functionalized arms composed of five nonpolar alkyl chains and five polar ester chains, and showed good separation performance for diverse types of analytes and isomers (apolar/polar, aliphatic/aromatic). Particularly, the AP5A-C10-OAc phase showed high selectivity for the challenging isomers of chloronitrobenzenes, bromonitrobenzenes, benzenediols, and iodoanilines with distinct advantages if compared with the commercial polysiloxane column.
研究领域:
分析化学
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色谱科学
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DOI
高影响因子
CHEMISTRY & BIODIVERSITY
·
2023
·Vol. 20
·期 8
·e202300350
·
IF 2.9
Mengyi Ba,Ruonan Chen,Qiuchen Huang,Yanli Song,Wen Li,Yuanyuan Zhang,Haixin Liu,Xiang Xu,Weidong Zhang,Zhiqiang Cai,Tao Sun
This work firstly reported a new polycaprolactone based material functionalized with guanidinium ionic liquid (PCL-GIL) as the stationary phase with high resolution performance for capillary gas chromatography (GC). It is composed of polycaprolactone (PCL) and guanidinium ionic liquid (GIL) with amphiphilic conformation. The PCL-GIL capillary column coated by static method exhibited high column efficiency of 3942 plates/m and moderate polarity. As a result, the PCL-GIL column exhibited high-resolution capability. For a mixture of 27 analytes with a wide ranging polarity and outperformed the PCL-2OH and HP-35 columns, showing its advantageous separation capability for analytes of diverse types. Moreover, the PCL-GIL column showed high resolving capability for various positional isomers and cis-/trans- isomers, including alkylbenzenes, chlorobenzenes, naphthalenes, bromonitrobenzenes, chloronitrobenzenes, benzaldehydes, phenols, alcohols, respectively. In a word, PCL derivatized by GIL units as a new type of stationary phase has a promising future in GC separations. Graphical
研究领域:
分析化学
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材料科学
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高影响因子
MICROCHIMICA ACTA
·
2021
·Vol. 188
·期 9
·1-10
·
IF 5.833
Guo Ping,Yuan Bao-Yan,Yu Yun-Yan,Zhang Jun-Hui,Wang Bang-Jin,Xie Sheng-Ming,Yuan Li-Ming
The fascinating framework structures and unique properties of chiral covalent organic frameworks (COFs) make them promising candidates as novel separation medium for high-performance liquid chromatography (HPLC). However, the irregular morphology, inhomogeneous particle size, and low density of conventional COF particles will lead to a low column efficiency, undesirable chromatographic peak shape, and high column backpressure of such COF-packed columns. In this work, a chiral COF CTpBD was synthesized by the Schiff base reaction between benzidine (BD) and chiral organic monomer CTp obtained through the reaction of 1,3,5-triformylphoroglucinol (Tp) and (+)-diacetyl-L-tartaric anhydride ((+)-Ac-L-Ta). The chiral COF CTpBD was immobilized on the surface of amino functionalized silica (SiO 2 -NH 2 ) by an in situ growth approach to prepare the chiral COF core-shell microsphere composite CTpBD@SiO 2 , which was used as a novel chiral stationary phase (CSP) for HPLC enantioseparation. Various kinds of racemates were separated on the CTpBD@SiO 2 -packed column with a low column backpressure (8–11 bar). Some effects such as the analyte mass and column temperature on the HPLC enantioseparation have been studied in detail. The fabricated CTpBD@SiO 2 -packed column exhibited high column efficiency (e.g., 16,800 plates m −1 for atenolol), high enantioselectivity, and good reproducibility toward various racemates. The highest resolution value, retention factor, and separation factor reach to 2.11, 2.85, and 3.73, respectively. The relative standard deviations (RSD) of peak area, peak height, half-peak width, and retention time of atenolol were all below 3.0%. Graphical abstract
研究领域:
分析化学
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色谱技术
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PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2013
·
IF 4.612
Wenjing Niu,Lijuan Wang,Ligai Bai,Gengliang Yang
A new polymeric monolith was synthesized in fused-silica capillary by in situ polymerization technique. In the polymerization, bisphenol A epoxy vinyl ester resin (VER) was used as the functional monomer, ethylene glycol dimethacrylate (EDMA) as the crosslinking monomer, 1,4-butanediol, 1-propanol and water as the co-porogens, and azobisisobutyronitrile (AIBN) as the initiator. The conditions of polymerization have been optimized. Morphology of the prepared poly (VER-co-EDMA) monolith was investigated by the scanning electron microscopy (SEM); pore properties were assayed by mercury porosimetry and nitrogen adsorption. The optimized poly (VER-co-EDMA) monolith showed a uniform structure, good permeability and mechanical stability. Then, the column was used as the stationary phase of high performance liquid chromatography (HPLC) to separate the mixture of benzene derivatives. The best column efficiency achieved for phenol was 235 790 theoretical plates per meter. Baseline separations of benzene derivatives and halogenated benzene compounds under optimized isocratic mode conditions were achieved with high column efficiency. The column showed good reproducibility: the relative standard deviation (RSD) values based on the retention times ( n = 3) for run-to-run, column-to-column and batch-to-batch were less than 0.98, 1.68, 5.48%, respectively. Compared with poly (BMA-co-EDMA) monolithic column, the proposed monolith exhibited more efficiency in the separation of small molecules.
研究领域:
分析化学
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材料科学
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产品关联
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PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
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2018
·
IF 3.716
Yan-Xia Li,Shi-Guo Fu,Jun-Hui Zhang,Sheng-Ming Xie,Lang Li,Yu-Yu He,Min Zi,Li-Ming Yuan
A highly ordered chiral mesoporous silica-coated capillary column has been used for high-resolution gas chromatographic separations. The column has excellent selectivity, not only for the separation of isomers, polycyclic aromatic hydrocarbons, linear alkanes, long chain alkanes, Grob’s test mixture and aromatic hydrocarbons, but also for the resolution of different classes of chiral compounds. Additionally, the column exhibits high column efficiency, excellent temperature resistance, and analysis times are short. This is the first report of a highly ordered chiral inorganic mesoporous silica used in separation science.
研究领域:
分析化学
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材料科学
✓ 已验证
DOI
高影响因子