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Cardenas Contreras EM, Tanis E, Lanças FM, Vargas Medina DA. Exploring a reversible adaptation of conventional HPLC for capillary-scale operation. J Chromatogr A 2024; 1730:465021. [PMID: 38897112 DOI: 10.1016/j.chroma.2024.465021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 05/21/2024] [Accepted: 05/22/2024] [Indexed: 06/21/2024]
Abstract
This study introduces a feasible approach for utilizing a conventional High-Performance Liquid Chromatography (HPLC) instrument at the capillary scale (1 - 10 µL/min). The development of an active flow splitter and an adapted UV-visible (UV-vis) detection cell are described. The system employs an Arduino Uno board to monitor a flow sensor and control a stepper motor that automates a split valve to achieve capillary-scale flow rates from a conventional pump. A capillary UV-vis cell compatible with conventional detectors, featuring an optical path length with a volume of 14 nL, was developed to address the detection challenges at this scale and minimize extra column band broadening. The system performance was assessed by a lab-packed LC capillary column with 0.25 mm x 15 cm dimensions packed with 3.0 µm C18 particles. Model compounds, particularly polycyclic aromatic hydrocarbons (PAHs), were employed to assess the functionality of all developed components in terms of theoretical plates, resolution, and band broadening. The proposed system is a profitable, reliable, and cost-effective tool for miniaturized liquid chromatography.
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Affiliation(s)
| | - Elton Tanis
- Nano Separations Technologies, São Carlos, Brazil
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2
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Ishida A, Nishimura T, Koyama K, Maeki M, Tani H, Tokeshi M. A portable liquid chromatography system based on a separation/detection chip module consisting of a replaceable ultraviolet-visible absorbance or contactless conductivity detection unit. J Chromatogr A 2023; 1706:464272. [PMID: 37595418 DOI: 10.1016/j.chroma.2023.464272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 07/31/2023] [Accepted: 08/01/2023] [Indexed: 08/20/2023]
Abstract
Recently, there has been a growing demand for miniaturized analytical instruments, including portable HPLC systems, that can enable rapid analysis in the field. This study aimed to develop chip-based separation/detection modules with replaceable detection units for constructing compact HPLC systems to minimize the dead volume. This module provides a tubing-free connection between the column and the detection unit. This study also built detection units for conductivity detection and ultraviolet-visible (UV-Vis) detection to cover a wide variety of inorganic and organic compounds. Furthermore, UV- and Vis-light-emitting diodes were employed for the absorbance detection unit. In addition, portable all-in-one HPLC systems and a handy HPLC system were constructed for ion chromatography and reversed-phase chromatography, demonstrating the successful separation and detection of inorganic ions and several organic compounds.
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Affiliation(s)
- Akihiko Ishida
- Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Sapporo 060-8628, Japan.
| | - Takuma Nishimura
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Kita 13 Nishi 8, Sapporo 060-8628, Japan
| | - Kaito Koyama
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Kita 13 Nishi 8, Sapporo 060-8628, Japan
| | - Masatoshi Maeki
- Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Sapporo 060-8628, Japan
| | - Hirofumi Tani
- Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Sapporo 060-8628, Japan
| | - Manabu Tokeshi
- Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Sapporo 060-8628, Japan
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3
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Towards in field miniaturized liquid chromatography: biocides in wastewater as a proof of concept. J Chromatogr A 2022; 1673:463119. [DOI: 10.1016/j.chroma.2022.463119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/22/2022] [Accepted: 05/02/2022] [Indexed: 11/18/2022]
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4
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[Research advances in nano liquid chromatography instrumentation]. Se Pu 2021; 39:1065-1076. [PMID: 34505428 PMCID: PMC9404240 DOI: 10.3724/sp.j.1123.2021.06017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
小型化是液相色谱分离技术发展的重要趋势之一,包括仪器外形尺寸的小型化、分离材料粒径的小型化以及色谱柱内径的小型化。色谱柱内径的减小能够降低样品和流动相的消耗,具有更高的质量灵敏度,特别适合用于复杂样品体系的分离分析。纳升液相色谱一般是指使用内径小于100 μm的毛细管色谱柱,流速范围在每分钟几十至几百纳升的色谱技术。由于流速很低,色谱柱体积很小,柱外效应显著,因此对色谱仪器系统各个模块的性能以及系统柱外效应的优化提出了较高的要求。纳升液相色谱的输液装置需要能够准确稳定地输送纳升级流速,具有梯度输液模式,且拥有一定的耐压能力,以适应不同规格的色谱柱类型;进样装置需要能够进行准确重复的进样过程,进样体积及进样方式适合毛细管色谱柱,同时不产生明显的柱外效应;检测装置需要具有较高的灵敏度,且具有较小的柱外扩散;管路与连接系统需要稳定、可靠、易操作,并能够最大限度地减小柱外体积,适配纳升级流速。鉴于目前大多数纳升液相色谱系统与质谱检测器联用,因而本文主要从输液装置、进样装置、管路与连接3个方面对相关技术领域的研究论文、技术专利以及仪器厂商的宣传文件等进行了检索与归纳,综述了这些模块的技术路线与研究进展,同时简要介绍光学吸收型检测装置的优化思路与研究进展,并对部分商品化的纳升液相色谱系统进行了对比。
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Davis JJ, Foster SW, Grinias JP. Low-cost and open-source strategies for chemical separations. J Chromatogr A 2021; 1638:461820. [PMID: 33453654 PMCID: PMC7870555 DOI: 10.1016/j.chroma.2020.461820] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/12/2020] [Accepted: 12/14/2020] [Indexed: 12/18/2022]
Abstract
In recent years, a trend toward utilizing open access resources for laboratory research has begun. Open-source design strategies for scientific hardware rely upon the use of widely available parts, especially those that can be directly printed using additive manufacturing techniques and electronic components that can be connected to low-cost microcontrollers. Open-source software eliminates the need for expensive commercial licenses and provides the opportunity to design programs for specific needs. In this review, the impact of the "open-source movement" within the field of chemical separations is described, primarily through a comprehensive look at research in this area over the past five years. Topics that are covered include general laboratory equipment, sample preparation techniques, separations-based analysis, detection strategies, electronic system control, and software for data processing. Remaining hurdles and possible opportunities for further adoption of open-source approaches in the context of these separations-related topics are also discussed.
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Affiliation(s)
- Joshua J Davis
- Department of Chemistry & Biochemistry, Rowan University, Glassboro, NJ 08028, United States
| | - Samuel W Foster
- Department of Chemistry & Biochemistry, Rowan University, Glassboro, NJ 08028, United States
| | - James P Grinias
- Department of Chemistry & Biochemistry, Rowan University, Glassboro, NJ 08028, United States.
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6
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Lankelma J, van Iperen DJ, van der Sluis PJ. Towards using high-performance liquid chromatography at home. J Chromatogr A 2021; 1639:461925. [PMID: 33556779 DOI: 10.1016/j.chroma.2021.461925] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 01/13/2021] [Accepted: 01/16/2021] [Indexed: 12/26/2022]
Abstract
In order to make high-performance liquid chromatography (HPLC) more widely available at home and in small-scale settings, we have simplified two of its most costly modules, namely the pump and the detector. This should make the setup affordable for home or small laboratory use. A manual HPLC pump was constructed so as to fit into a caulk gun from a local hardware store enabling the generation of 100-150 bar of pressure. In order to limit the pressure drop during the running of a chromatogram, a pulse dampener was developed. We further modified the electrochemical detection (ECD) system so as to use a cheap boron-doped diamond electrode with an overlay of thin filter paper, causing an eluent flow over the electrode by wicking and gravity. Both the pump and the detector are at least ten times cheaper than conventional HPLC modules. Using a home-packed JupiterⓇ Proteo reversed phase capillary column we show how this low-cost HPLC system generates well resolving chromatograms after direct injection of fresh urine. The ECD did not lose its sensitivity during regular use over more than half a year. For homovanillic acid (HVA), which is of medical interest, we measured a linear dynamic range of two orders of magnitude, a detection limit of HVA in the injected sample of 3 μM and a coefficient of variation <10%. The contribution to peak broadening by the detector was much smaller than the contributions by the injector and by the column. After consumption of table olives containing hydroxytyrosol (HT), its metabolite HVA in the corresponding urine could be measured quantitatively. An approach to quantify HT in table olives is presented, as well. This method provides a new tool for investigating physiology of oneself or of dear ones at home.
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Affiliation(s)
- Jan Lankelma
- Department of Molecular Cell Physiology, VU University Amsterdam, O
- 2 Lab Building, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands; Foundation for Chromatography at home, Demonstrator Lab, Amsterdam, The Netherlands.
| | - Dirck J van Iperen
- Department of Fine mechanics and Engineering VU - Bèta, VU University Amsterdam, The Netherlands
| | - Paul J van der Sluis
- Foundation for Chromatography at home, Demonstrator Lab, Amsterdam, The Netherlands
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7
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Miniaturization of liquid chromatography coupled to mass spectrometry. 3. Achievements on chip-based LC–MS devices. Trends Analyt Chem 2020. [DOI: 10.1016/j.trac.2020.116003] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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8
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Abstract
AbstractThere is a growing need for chemical analyses to be performed in the field, at the point of need. Tools and techniques often found in analytical chemistry laboratories are necessary in performing these analyses, yet have, historically, been unable to do so owing to their size, cost and complexity. Technical advances in miniaturisation and liquid chromatography are enabling the translation of these techniques out of the laboratory, and into the field. Here we examine the advances that are enabling portable liquid chromatography (LC). We explore the evolution of portable instrumentation from its inception to the most recent advances, highlighting the trends in the field and discussing the necessary criteria for developing in-field solutions. While instrumentation is becoming more capable it has yet to find adoption outside of research.
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9
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Coates LJ, Lam SC, Gooley AA, Haddad PR, Paull B, Wirth HJ. Modular, cost-effective, and portable capillary gradient liquid chromatography system for on-site analysis. J Chromatogr A 2020; 1626:461374. [PMID: 32797852 DOI: 10.1016/j.chroma.2020.461374] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 06/10/2020] [Accepted: 06/27/2020] [Indexed: 02/08/2023]
Abstract
This work demonstrates the development of a compact, modular, cost-effective separation system configured to address a specific separation problem. The principles of the separation are based on gradient capillary liquid chromatography where the system consists of precision stepper motor-driven portable syringe pumps with interchangeable glass syringes (100 µL to 1000 µL). Excellent flow-rate precision of < 1% RSD was achieved with typical flow-rates ranging from 1 µL/min to 100 µL/min, which was ideal for capillary columns. A variable external loop volume and electrically actuated miniature injection valve was used for sample introduction. Detection was based upon a commercial Z-type UV absorbance flow-cell housed within a custom-built cooling enclosure (40 mm x 40 mm) which also contained a UV-LED light-source and a photodiode. System and chromatographic performance was evaluated using linear gradient elution, with day to day repeatability of <1.5% RSD (n = 6) for peak area, and < 0.4% RSD (n = 6) for retention time, for the separation of a 5 component mixture using a 50 mm X 530 µm ID C18 3 µm particle capillary column. The system can run any commercial or in-house packed columns from 50 mm to 100 mm length with IDs ranging from 200 to 700 µm. The developed portable system was operated using custom-built windows-based chromatography software, complete with data acquisition and system control.
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Affiliation(s)
- Lewellwyn J Coates
- ARC Centre for Portable Analytical Technologies (ASTech), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart 7000, Tasmania, Australia; Trajan Scientific and Medical, 7 Argent Place, Ringwood, Victoria 3134, Australia
| | - Shing C Lam
- ARC Centre for Portable Analytical Technologies (ASTech), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart 7000, Tasmania, Australia; Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart 7000, Tasmania, Australia
| | - Andrew A Gooley
- ARC Centre for Portable Analytical Technologies (ASTech), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart 7000, Tasmania, Australia; Trajan Scientific and Medical, 7 Argent Place, Ringwood, Victoria 3134, Australia
| | - Paul R Haddad
- ARC Centre for Portable Analytical Technologies (ASTech), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart 7000, Tasmania, Australia; Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart 7000, Tasmania, Australia
| | - Brett Paull
- ARC Centre for Portable Analytical Technologies (ASTech), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart 7000, Tasmania, Australia; Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart 7000, Tasmania, Australia
| | - Hans-Jürgen Wirth
- ARC Centre for Portable Analytical Technologies (ASTech), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart 7000, Tasmania, Australia; Trajan Scientific and Medical, 7 Argent Place, Ringwood, Victoria 3134, Australia.
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10
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Lam SC, Coates LJ, Hemida M, Gupta V, Haddad PR, Macka M, Paull B. Miniature and fully portable gradient capillary liquid chromatograph. Anal Chim Acta 2019; 1101:199-210. [PMID: 32029112 DOI: 10.1016/j.aca.2019.12.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 12/05/2019] [Accepted: 12/06/2019] [Indexed: 12/24/2022]
Abstract
A robust, portable and miniature battery powered gradient capillary liquid chromatograph (total weight ∼2.7 kg, without battery ∼2.0 kg), with integrated microfluidic injection, column heating and high sensitivity low-UV absorbance detection is presented. The portable capillary chromatograph, was applied with a packed reversed-phase capillary column (100 mm × 300 μm I.D., 5 μm ODS), housed within an integrated capillary column heater controlled by a proportional-integral-derivative (PID) chip module. The system delivered retention time and peak area relative standard deviation in isocratic mode of <0.7% (n = 10) and <3.3% (n = 10), respectively, and <0.1% (n = 10) and <2.3% (n = 10) respectively, for gradient elution mode. Detection was based upon a 255 nm light-emitting diode (LED) using one of two commercial capillary flow-cell options, namely a high sensitivity 12 nL Agilent capillary z-cell (HSDC) and a 45 nL Thermo Fisher Scientific UZ-View™ flow cell (UZFC). The HSDC, housed within a 3D printed detector arrangement, gave an effective pathlength of 1.01 mm (84% of nominal pathlength) and stray light of only 0.2%. Limits of detection for four test small molecule pharmaceuticals ranged from 65 to 101 μg L-1 based upon a 316 nL injection volume, with separation efficiencies of between 18,000 and 29,700 N m-1, with sub-4 min run times. The portable capillary LC system was successfully coupled to a small footprint portable mass spectrometer (Microsaic 4500 MiD) to demonstrate compatibility and 'point-of-need' miniaturised LC-MS capability.
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Affiliation(s)
- Shing Chung Lam
- ARC Training Centre for Portable Analytical Separation Technologies (ASTech), University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia; Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia
| | - Lewellwyn Joseph Coates
- ARC Training Centre for Portable Analytical Separation Technologies (ASTech), University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia; Trajan Scientific and Medical, Ringwood, Victoria, 3134, Australia
| | - Mohamed Hemida
- ARC Training Centre for Portable Analytical Separation Technologies (ASTech), University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia; Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia
| | - Vipul Gupta
- Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia
| | - Paul R Haddad
- ARC Training Centre for Portable Analytical Separation Technologies (ASTech), University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia; Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia
| | - Mirek Macka
- Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia; Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, 613 00, Brno, Czech Republic; Central European Institute of Technology, Brno University of Technology, Purkynova 123, 612 00, Brno, Czech Republic
| | - Brett Paull
- ARC Training Centre for Portable Analytical Separation Technologies (ASTech), University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia; Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia.
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11
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Chatzimichail S, Casey D, Salehi-Reyhani A. Zero electrical power pump for portable high-performance liquid chromatography. Analyst 2019; 144:6207-6213. [PMID: 31573005 DOI: 10.1039/c9an01302d] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A major trend in analytical chemistry is the miniaturization of laboratory instrumentation. We report a pump requiring no power to operate based on the controlled expansion of a pre-pressurised gas for use in portable applications of high-performance liquid chromatography. The performance of the gas pump is characterised and integrated into a compact liquid chromatography system capable of isocratic separations integrating an LED-based UV-absorption detector. The system weighed 6.7 kg when the mobile phase reservoir was fully charged with 150 mL solvent and included an on-board computer to control the system and analyse data. We characterise the flow-rate through chromatography columns with a variety of geometries and packing materials for a range of pressures up to 150 bar. The maximum variation in flow rate was measured to be 6.5 nL min-1, limited by the resolution of the flow detector. All tests were made on battery power and results are a mixture of those made in the laboratory and in the field. Additionally, we performed a series of 1 m drop tests on the device and show the system's high tolerance to mechanical shocks during operation in the field.
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Affiliation(s)
- Stelios Chatzimichail
- Department of Chemistry, King's College London, Britannia House, 7 Trinity Street, London, SE1 1DB, UK.
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12
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Li L, Wang X, Pu Q, Liu S. Advancement of electroosmotic pump in microflow analysis: A review. Anal Chim Acta 2019; 1060:1-16. [PMID: 30902323 DOI: 10.1016/j.aca.2019.02.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 02/07/2019] [Accepted: 02/09/2019] [Indexed: 01/21/2023]
Abstract
This review (with 152 references) covers the progress made in the development and application of electroosmotic pumps in a period from 2009 through 2018 in microflow analysis. Following a short introduction, the review first categorizes various electroosmotic pumps into five subclasses based on the materials used for pumping: i) open channel EOP, 2) packed-column EOP, iii) porous monolith EOP, iv) porous membrane EOP, and v) other types of EOP. Pumps in each subclass are discussed. A next section covers EOP applications, primarily the applications of EOPs in micro flow analysis and micro/nano liquid chromatography. Other scattered applications are also examined. Perspectives, trends and challenges are discussed in the final section.
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Affiliation(s)
- Lin Li
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, 730000, PR China
| | - Xiayan Wang
- College of Environmental and Energy Engineering, Beijing University of Technology, Beijing, 100124, PR China
| | - Qiaosheng Pu
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, 730000, PR China.
| | - Shaorong Liu
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK, 73019, United States.
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13
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Lynch KB, Chen A, Liu S. Miniaturized high-performance liquid chromatography instrumentation. Talanta 2017; 177:94-103. [PMID: 29108588 DOI: 10.1016/j.talanta.2017.09.016] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 09/04/2017] [Accepted: 09/06/2017] [Indexed: 12/26/2022]
Abstract
Miniaturized high performance liquid chromatography (HPLC) has attracted increasing attention for its potential in high-throughput analyses and point-of-care applications. In this review we highlight the recent advancements in HPLC system miniaturization. We focus on the major components that constitute these instruments along with their respective advantages and drawbacks as well as present a few representative miniaturized HPLC systems. We discuss briefly some of the applications and also anticipate the future development trends of these instrumental platforms.
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Affiliation(s)
- Kyle B Lynch
- Department of Chemistry and Biochemistry, University of Oklahoma, USA.
| | - Apeng Chen
- Department of Chemistry and Biochemistry, University of Oklahoma, USA
| | - Shaorong Liu
- Department of Chemistry and Biochemistry, University of Oklahoma, USA
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