JOURNAL OF CHROMATOGRAPHY A
·
2013
·
IF 4.612
Mei Zhang,Jun-Hui Zhang,Yan Zhang,Bang-Jin Wang,Sheng-Ming Xie,Li-Ming Yuan
This study focused on exploring the chromatographic characteristic of a homochiral MOF [Cu 2 ( d -Cam) 2 (4,4′-bpy)] n with 3-D six-connected self-penetrating architectures for the separations of positional isomers and chiral compounds. Some effects such as mobile phase composition, column temperature, and analytes mass for separations on this chiral column also have been investigated. Among thirteen tested racemates, six compounds, namely three alcohols, a diol, a naphthol and a ketone were successfully discriminated, and ten useful positional isomers which have never been separated on other MOFs stationary phases in HPLC except dichlorobenzene and cresol isomers, were also analyzed by this chiral stationary phase. The results indicated that [Cu 2 ( d -Cam) 2 (4,4′-bpy)] n exhibited good selectivity for positional isomers and enantiomers. Therefore, it is practicable that the separation of positional isomers and enantiomers are carried out on the chiral MOF column.
研究领域:
分析化学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
Acta Chimica Slovaca
·
2021
·Vol. 14
·期 1
·60-65
·
IF 0
Laura Jánovová,Katarína Hroboňová
Lactic acid is a biologically important organic acid existing in two enantiomeric forms which are differently metabolized in the human body. In this paper, direct chiral separation of lactic acid by high performance liquid chromatography is presented. Five chiral stationary phases based on macrocyclic antibiotics were used for enantioseparation and chromatographic parameters, such as retention factors, resolution and selectivity factors, were determined under different column temperatures ranging from 5 to 45 °C. Optical isomers of lactic acid were efficiently separated using chiral stationary phases based on teicoplanin (RS = 1.9
) and ristocetin (RS = 1.7
) in reversed-phase separation mode at the column temperature of 25 °C.
研究领域:
分析化学
·
生物化学
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DOI
CHROMATOGRAPHIA
·
2019
·Vol. 83
·期 1
·107-113
·
IF 1.552
Zhou Feng,Ren Xianghong,Du Siyan
Abstract Current methods for measurement of unsymmetrical dimethylhydrazine (UDMH) in wastewater suffer from a small detection range and complex pretreatment. In this study, ion chromatography (IC) with conductivity detection was used to directly analyze UDMH in wastewater, without any derivatization pretreatment, and the measurement range was as wide as 0.5–1000 μg·mL −1 . The effects of column temperature and sample pH on the detection were investigated. Furthermore, the chromatography conditions were optimized by combining the effects of different combinations of nitric acid, 2,6-pyridinedicarboxylic acid (PDCA), and methanesulfonic acid (MSA) on the analysis of mixed samples of UDMH and alkali metal ions. The linearity of the detected peak height ( H ) and peak area ( A ) versus UDMH concentration was studied at low, medium, and high concentrations. A good linear relationship was observed in the range of 0.5–1000 μg·mL −1 , especially for A , the relative standard deviation (RSD) and correlation coefficient ( R 2 ) of which were 0.077–1.653% and 0.9998–1.0000, respectively. In addition, the method showed good sensitivity with a limit of detection (LOD) of 0.05 μg·mL −1 and a limit of quantitation (LOQ) of 0.16 μg mL −1 . The precision and accuracy (expressed by recovery) were verified, where the RSD were less than 1.49% and 3.17%. Interference between hydrazines and alkali metal ions was discussed. Finally, actual UDMH samples were determined, confirming the applicability of the developed method for analyzing UDMH in wastewater during the degradation process. Graphic Abstract
研究领域:
环境化学
·
分析化学
·
废水处理
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DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2023
·
IF 4.8
Zhefei Hu,Yanhao Jiang,Panpan Cao,Yanjuan Liu,Yuefei Zhang,Wei Chen,Sheng Tang
In this work, 2-undecylimidazole (UI) and propyl methacrylate (PMA) dual-functionalized silica gel was prepared and applied as a mixed-mode chromatographic stationary phase. Successful preparation of this stationary phase (SiO 2 -UI-PMA) was proved through a range of characterization techniques. The chromatographic performance of the obtained SiO 2 -UI-PMA was investigated for the separation of environmental endocrine disruptors (phthalates, steroid hormones, bisphenols and alkylphenols), sulfonamides and food-borne stimulants in reversed-phase chromatography, as well as for the separation of inorganic anions in anion-exchange chromatography. The effect of column temperature, acetonitrile content, salt concentration and mobile phase pH on retention was studied to explore the separation mechanism, and the results indicated that this stationary phase provided multiple interactions with analytes. Compared with the commercial C18 column, the SiO 2 -UI-PMA demonstrated more preferable separation ability under the mobile phase conditions with a low content of acetonitrile, thereby acting as a good alternative candidate for the conventional reversed-phase stationary phase in chromatographic analysis. Furthermore, the SiO 2 -UI-PMA stationary phase exhibited high column efficiency (45 860 plates m −1 for progesterone) even though it was prepared from the non-serviceable silica based chromatographic packing materials.
研究领域:
分析化学
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子