ANALYST
·
2024
·Vol. 149
·期 5
·1579-1585
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IF 3.6
Boxin Chen,Yuchen Zhu,Shaojie Ma,Bin Zhao,Fei Feng
A semi-packed gas chromatographic column has the advantages of high specific surface area and low column pressure. We report that the stagnation regions formed in the adjacent posts along the channel of the semi-packed columns can decrease the area and height of chromatographic peaks, which makes it difficult to detect low-concentration mixed gases. A semi-packed column with staggered elliptic cylindrical post arrays (SC-S) made using a micro-electro-mechanical system technique is presented, and the separation performance of SC-S is compared with that of a semi-packed column with aligned elliptic cylindrical post arrays (SC-A). The simulation results show that the width of stagnation regions in SC-S is 86.89% smaller than that in SC-A. The experimental results indicate that the area and height of chromatographic peaks increased as stagnation regions reduced. In the separation of the alkane mixture from C8 through C10 with 10 ppm concentration, the chromatographic peak of decane was hardly identified in SC-A while the chromatographic peak in SC-S was still clearly visible. The chromatographic peak heights of octane and nonane were increased by 65.06% and 130.00%, respectively, in SC-S. The peak areas of octane and nonane were increased by 120.45% and 168.18%, respectively.
研究领域:
分析化学
·
微机电系统技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2019
·
IF 3.858
Jiannan Sun,Shiwei Yang,Heyong Cheng,Yuanchao Wang,Jinhua Liu
Further development of capillary electrochromatography (CEC) is to some extent restricted by column technology. Packed capillary columns are most commonly used in CEC because of higher sample capacity and higher sensitivity than open tubular columns, and better reproducibility and uniformity than monolithic columns. Fritting is the core component for the fabrication of packed capillary columns. Therefore various fritting technologies attract continuous attention from analytical community. A convenient fritting method was developed in this study. In contrast to the reported single-particle fritting, this method applies a multi-particle fritting technology to hold stationary phase in capillary columns. Several large porous particles smaller than the column internal diameter were tapped in and immobilized in inlet and outlet of the packing material bed due to direct and indirect keystone effect. Except the smallest permeability by the sintered frit and the lowest breaking pressure by the single-particle frit, EOF mobility and peak dispersion of the multi-particle frit were at the same levels with the formers. In addition, all the three frits avoided bubble formation. It demonstrated that the multi-particle frits met the general requirements of permeability, mechanical resistance and efficiency for packing capillary microcolumns as well as the sintered frits and the single-particle frits. Thus, peak efficiency around 4.3 μm plate height (approximately 232,560 plates per meter) was obtained by multi-particle fritted capillary columns with electrokinetic packing, compared to 6.5 μm plate height by single-particle fritted columns with slurry pressure packing. In particular, the multi-particle fritting was simpler, faster, and more reproducible than the sintered fritting, and the multi-particle fritting was suitable to pack capillary columns of various capillary bore sizes owing to rich commercial resources of fritting particles of various diameters. Multi-particle fritted columns offered satisfactory run-to-run and column-to-column reproducibilities for retention factor, plate height and peak area (precisions of 4.1–9.3% for 10 replicated columns, and precisions of 0.9–3.1% for 30 replicated trials). They also had consistent CEC performance (differences of 1.1–3.9% between the first and 31 st day) during a lifetime more than one month. Application examples in packing capillary columns of 75 and 100 μm i.d. and CEC analysis of sixteen polycyclic aromatic hydrocarbons prove the diversity and reliability of the multi-particle fritting in column technology.
研究领域:
分析化学
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分离科学
·
色谱技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2021
·
IF 4.759
Boxin Chen,Fei Feng,Yangyang Zhao,Qiyong Liu,Bin Zhao,Lei Li,Haimei Zhou,Xinxin Li
Semi-packed columns are microfabricated gas chromatography columns which have a large surface area and high aspect ratio. In this paper, a new semi-packed column with high-density elliptic cylindrical posts (SC HECP) made by a micro-electro-mechanical system (MEMS) technique was reported. Compared to a semi-packed column with cylindrical posts (SC CP) under the same effective width, the surface area and aspect ratio of SC HECP were improved by 71.19% and 76.47%, respectively. To compare the performance of these two semi-packed columns, SC HECP and SC CP were fabricated. A 10-nm thick alumina film was deposited as the stationary phase by atomic layer deposition technique to ensure the uniformity and repeatability of the stationary-phase film. A contrast experiment was conducted, and the results showed that compared with SC CP, better separation performance was realized in SC HECP due to the increase in surface area and aspect ratio. The number of theoretical plates of nonane was increased by 541.84%, and the tailing factor was decreased by 54.31%.
研究领域:
分析化学
·
微纳米技术
·
色谱技术
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2019
·
IF 5.256
Yonglei Wu,Haizhu Lin,Zixing Xu,Yan Li,Zongbao Chen,Chunhui Deng
In this work, for the first time, L -cysteine ( L -Cys), a zwitterionic hydrophilic compound containing abundant amino and carboxyl was modified on silica microspheres for the fabrication of SiO 2 @ L -Cys capillary packed column. Since the SiO 2 @ L -Cys capillary packed column possessed great hydrophilicity brought by L -cysteine, they could be utilized to enrich glycopeptides with a low detection limit of 5 fmol μL −1 HRP digests as well as a good selectivity of the mixture of HRP and BSA digests up to a molar ratio of 1:50. The capillary packed column were further applied into the glycosylation analysis of human saliva and 69 glycopeptides were identified from 2 μL human saliva digests.
研究领域:
分析化学
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生物化学
·
蛋白质组学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 38
·26214-26223
·
IF 10.7
Hai-Long He,Zhongqi Liu,Fengqing Liu,Jie Chen,Pu Wang,Xianfeng Yi,Anmin Zheng,Lei Wang
Fructose is an essential raw material for the biorefinery industry and can be produced from glucose via catalytic isomerization; however, efficient separation to obtain high-purity fructose from glucose/fructose mixed solution remains a challenge. In this study, MOF-808 with a 6-connected Zr6 node was employed as an adsorbent, and its adsorption and separation performances for fructose and glucose were investigated. MOF-808, whose pore size is 1.42 nm, exhibited a high adsorption selectivity factor of 17.8 for fructose. The adsorption process reached equilibrium within 5 h, and the adsorption capacity reached 362 mg g−1. We propose that the larger pore size MOF-808 exhibited higher selectivity for fructose than the previously reported NU-906 (1 nm) due to the increase in the number of zirconium (Zr) open metal sites, enhancing the selectivity of the pore environment and consequently expelling glucose from the pore. This hypothesis was verified by the adsorption selectivity of fructose and glucose in various defect concentrations of UiO-66, which acted as a tunable framework. In addition, the column packed with MOF-808 showed excellent performance, with an adsorption selectivity of 5.0 in the breakthrough experiment. This study demonstrated that MOF-808 with abundant Zr open metal sites could efficiently separate glucose and fructose, which can inspire the design of adsorbents for fructose purification.
研究领域:
化学工程
·
材料科学
·
分离科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Zanru Guo,Qiang Chen,Hongjian Gu,Zhanfeng He,Wenyuan Xu,Jiali Zhang,Yongxin Liu,Leyan Xiong,Longzhen Zheng,Yujun Feng
Adsorbents that are capable of controllable pollutants adsorption and release without secondary pollution are attractive in water treatment. Here, we propose eco-friendly CO2 as a trigger to switch the charge states and collapse–expansion transition of giant microgels consisting of hydrophilic acrylamide and hydrophobic 2-(diethylamino)ethyl methacrylate and demonstrated the on–off, selective, and recyclable adsorption of anionic dyes on microgels under CO2 stimulation. Apart from easy-handling separation from the water by a simple filtration process, the maximum adsorption capacity is as high as 821 mg g–1, and the adsorption isotherms and kinetics obeyed Langmuir isotherm and the pseudo-second-order kinetics models, respectively. The anionic dye can also be separated from the mixture solution using CO2-treated microgels. Moreover, a wastewater treatment prototype with microgel-packed column was fabricated. Under continuous flow condition, the dye was removed and recovered by alternative bubbling CO2 and flushing with aqueous alkali (pH 12). Thus, this type of microgels with CO2-induced protonation–deprotonation transition can serve as a cost-effective, environmentally friendly, and efficient adsorbent for water purification applications.
研究领域:
环境科学
·
化学工程
·
材料科学
·
水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）