MICROCHIMICA ACTA
·
2019
·Vol. 187
·期 1
·1-10
·
IF 5.479
Ding Wen,Yu Tao,Du Yingxiang,Sun Xiaodong,Feng Zijie,Zhao Shiyuan,Ma Xiaofei,Ma Mingxuan,Chen Cheng
Poly(glycidyl methacrylate)-co-(ethylene dimethacrylate) [poly(GMA-co-EDMA)] monoliths were used as a support to grow a zeolitic imidazolate framework-8 (ZIF-8) via layer-by-layer self-assembly. Pepsin, acting as as chiral selector, was covalently linked to the surface of the amino-modified ZIF-8 through the Schiff base method. The material was characterized by scanning electron microscopy, thermogravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy and elemental analysis. The pepsin-ZIF-8-poly(GMA-co-EDMA) column was utilized to the enantioseparation of the racemic forms of hydroxychloroquine (HCQ), chloroquine (CHQ), hydroxyzine (HXY), nefopam (NEF), clenbuterol (CLE) and amlodipine (AML). In comparison with a pepsin-poly(GMA-co-EDMA) monolithic column (without self-assembled ZIF-8 nanoparticles), the resolution is strongly enhanced (HCQ: 0.34 → 2.50; CHQ: 0.45 → 1.97; HXY: 0.39 → 1.43; NEF: 0.27 → 0.81; CLE: 0 → 0.81; AML: 0.16 → 0.72). Effects of self-assembly layers of ZIF-8, pepsin concentration, buffer pH values and applied voltage were investigated with hydroxychloroquine as the model analyte. The reproducibility of run-to-run, day-to-day and column-to-column were explored, and found to be satisfactory.
Schematic representation of capillary electrochromatography (CEC) systems with a pepsin-zeolitic imidazolate framework-8 (ZIF-8) modified poly(glycidyl methacrylate)-co-(ethylene dimethacrylate) [poly(GMA-co-EDMA)] monolithic column as stationary phases for separation of basic racemic drugs. ZIF-8 modified column was prepared via layer-by-layer self-assembly.
研究领域:
分析化学
·
药学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 3
·1-12
·
IF 6.232
Ma Mingxuan,Du Yingxiang,Yang Jiangxia,Feng Zijie,Ding Wen,Chen Cheng
Poly(glycidyl methacrylate)-co-(ethylene dimethacrylate) [poly(GMA-co-EDMA)] monoliths were prepared, and used as a support to attach gold nanoparticles (AuNP) via Au-S bond. Pepsin, acting as a chiral selector, was linked to the surface of the carboxyl-modified AuNP through a hydrochloride/N-hydroxysuccinimide coupling reaction. The material was characterized by scanning electron microscopy, energy dispersive X-ray spectrometry, transmission electron microscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy and N 2 adsorption-desorption isotherm. The pepsin@AuNP@poly(GMA-co-EDMA) monolith showed preferable enantioselectivity for hydroxychloroquine (HCQ), chloroquine (CHQ), hydroxyzine (HXY), labetalol (LAB), nefopam (NEF), clenbuterol (CLE), amlodipine (AML) and chlorpheniramine (CHL) in capillary electrochromatography (CEC). These racemic drugs were monitored at the maximum absorption wavelength (220 nm for HXQ, CHQ, HXY, LAB, NEF; 240 nm for AML; 215 nm for CLE, CHL). In comparison with the pepsin@poly(GMA-co-EDMA) monolith loaded with 5 nm AuNP, the pepsin@poly(GMA-co-EDMA) monolith loaded with 13 nm AuNP shows significantly enhanced enantiomeric resolution (HCQ: 0.62 → 3.45; CHQ: 0.60 → 2.11; HXY: 0.49 → 2.30; LAB: 1.03 → 2.45, 1.45 → 3.46, 0 → 0.67; NEF: 0.53 → 1.29; CLE: 0.42 → 0.56; AML: 0 → 0.83; CHL: 0.24 → 0.55). Pepsin concentration, buffer pH value, buffer concentration and applied voltage were investigated in detail with (±) HCQ and (±) HXY as model analytes. The reproducibility of intra-day, inter-day and column-to-column were explored, and found to be satisfactory.
Schematic presentation of the preparation of gold nanoparticles (AuNP) modified.
研究领域:
分析化学
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纳米技术
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药学
·
分离科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2020
·
IF 4.049
Mingxuan Ma,Cheng Chen,Xinqi Zhu,Xiaoqi Li,Yingxiang Du,Liu Zhang,Jie Gan
New material zeolitic imidazolate framework-4, 5-imidazoledicarboxylic acid (ZIF-IMD) located on the pore surface of porous layer open-tubular (PLOT) column previously functionalized with N-(3-aminopropyl)-imidazole have been prepared via a layer-by-layer self-assembly strategy. This new ZIF-IMD coating hybrids are used as solid-phase carriers for chiral selector pepsin immobilization. The ZIF-IMD material was characterized by scanning electron microscopy, energy-dispersive spectroscopy, transmission electron microscope and X-ray diffraction. The synthesized pepsin@ZIF-IMD@POLT column achieved the baseline separation of hydroxychloroquine (HCQ), chloroquine (CHQ) and hydroxyzine (HXY) (the resolution of HCQ: 2.19; CHQ: 1.84; HXY: 1.53). Compared with the pepsin@PLOT column (without ZIF-IMD material), the chiral separation capability of the pepsin@ZIF-IMD@POLT column can be remarkably improved. Several key parameters including concentration of chiral selector, buffer pH, applied voltage and buffer concentration were systematically evaluated to provide the optimal enantioseparation condition. The relative standard deviations (RSDs) of intra-day, inter-day, column-to-column and inter-batch of migration time and Rs of the HCQ were evaluated in detail, respectively (RSD < 7.21%). Additionally, the potential mechanism of increased resolution was discussed in the article.
研究领域:
分析化学
·
材料科学
·
药物分析
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2024
·
IF 5.6
Lu Wang,Limei Xiao,Shoujing Zheng,Jie Pang,Jiebo Chen
A better understanding of amino acids (AA) characteristics is beneficial for breeding, processing and storage of sugarcane. The differences and classification in AA of 10 different sugarcane varieties (S1-S10) were investigated in this study. Varieties affected components and concentrations of free AA ( p ＜ 0.05) significantly. The total AA of sugarcanes ranged from 51.44 to 781.61 mg/L, while the content of essential amino acids (EAA) was in the range of 0.72–60.98 mg/L. Glu (glutamic acid) was the most abundant free amino acids in all varieties of sugarcane except S4. Even though S6 had the highest concentration of medicinal AA (781.61 mg/L), the highest proportion of medicinal AA in total AA was found in S5 (81.76%). S6 got the highest comprehensive score in amino acids based on the results of Principal Component Analysis (PCA). The cluster analysis roughly divided the sugarcanes into 2 groups. Group Ⅰ including S1, S6, S2 and S5 got positive scores in PCA might had great edible and medicinal development and utilization value.
研究领域:
食品科学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）