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Song Y, Zhou Y, Zhang K, Fan Z, Zhang F, Wei M. Microfluidic programmable strategies for channels and flow. LAB ON A CHIP 2024. [PMID: 39120605 DOI: 10.1039/d4lc00423j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/10/2024]
Abstract
This review summarizes programmable microfluidics, an advanced method for precise fluid control in microfluidic technology through microchannel design or liquid properties, referring to microvalves, micropumps, digital microfluidics, multiplexers, micromixers, slip-, and block-based configurations. Different microvalve types, including electrokinetic, hydraulic/pneumatic, pinch, phase-change and check valves, cater to diverse experimental needs. Programmable micropumps, such as passive and active micropumps, play a crucial role in achieving precise fluid control and automation. Due to their small size and high integration, microvalves and micropumps are widely used in medical devices and biological analysis. In addition, this review provides an in-depth exploration of the applications of digital microfluidics, multiplexed microfluidics, and mixer-based microfluidics in the manipulation of liquid movement, mixing, and splitting. These methodologies leverage the physical properties of liquids, such as capillary forces and dielectric forces, to achieve precise control over fluid dynamics. SlipChip technology, which branches into rotational SlipChip and translational SlipChip, controls fluid through sliding motion of the microchannel. On the other hand, innovative designs in microfluidic systems pursue better modularity, reconfigurability and ease of assembly. Different assembly strategies, from one-dimensional assembly blocks and two-dimensional Lego®-style blocks to three-dimensional reconfigurable modules, aim to enhance flexibility and accessibility. These technologies enhance user-friendliness and accessibility by offering integrated control systems, making them potentially usable outside of specialized technical labs. Microfluidic programmable strategies for channels and flow hold promising applications in biomedical research, chemical analysis and drug screening, providing theoretical and practical guidance for broader utilization in scientific research and practical applications.
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Affiliation(s)
- Yongxian Song
- School of Electronic Engineering, Nanjing Xiaozhuang University, Nanjing, Jiangsu 211171, China.
| | - Yijiang Zhou
- School of Electrical and Information Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China.
| | - Kai Zhang
- School of Automation, Huaiyin Institute of Technology, Huaian, 223003, China.
| | - Zhaoxuan Fan
- Research Institute of Chemical Defence, Beijing 102205, China.
| | - Fei Zhang
- School of Electrical and Information Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China.
| | - Mingji Wei
- School of Electrical and Information Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China.
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Non-monotonic dependence of induced-charge electro-osmosis on ion concentration. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.126604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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3
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Latiyan S, Suneet K, Jain S. Magneto-conducting multifunctional Janus microbots for intracellular delivery of biomolecules. J Tissue Eng Regen Med 2021; 15:625-633. [PMID: 33847076 DOI: 10.1002/term.3199] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 11/04/2020] [Accepted: 04/05/2021] [Indexed: 11/08/2022]
Abstract
Although several advances have been made in the field of medicine during the last few decades, yet targeted delivery of biomolecules is still a significant challenge. Thus, the present study illustrates the fabrication of dual nature magneto-conducting Fe3 O4 -SU8 derived carbon-based Janus microbots that could deliver biomolecules efficiently inside cells. These microsystems possess dual properties, that is, the half part is magneto-conducting, and another half is only conducting for sufficing the therapeutic payloads efficiently under electromagnetic stimulations. These microbots are intrinsically fluorescent, which can help to trace them intracellularly without using any dye. UV photolithography was employed to design these low aspect ratio microbots (feature size ∼2.5 μm diameter and 3.7 μm length) for attaining better control over locomotion with minimum magnetic field intensity. Interestingly, Janus microbots achieved a higher speed in the electric field (44 µm/s) as compared to the magnetic field (18 µm/s). Moreover, in vitro studies show a higher microbots uptake by HeLa cells in the presence of an external electric field as compared to without electrical field stimulation.
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Affiliation(s)
- Sachin Latiyan
- Centre Biosystems Science and Engineering, Indian Institute of Science, Bengaluru, India
| | - Kaushik Suneet
- Centre Biosystems Science and Engineering, Indian Institute of Science, Bengaluru, India
| | - Shilpee Jain
- Centre Biosystems Science and Engineering, Indian Institute of Science, Bengaluru, India
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Recent advancement in induced-charge electrokinetic phenomena and their micro- and nano-fluidic applications. Adv Colloid Interface Sci 2020; 280:102159. [PMID: 32344205 DOI: 10.1016/j.cis.2020.102159] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 04/11/2020] [Accepted: 04/12/2020] [Indexed: 11/21/2022]
Abstract
Induced-charge electrokinetics (ICEK) remains a hot topic due to its promising applications in micro- and nano-fluidics. Over the past decade, researchers have made a great advancement in both fundamental studies and application developments. They captured (I) a flow reversal in induced-charge electroosmosis (ICEO) and attributed it to the phase delay effect of ions, (II) a chaotic ICEO and attributed it to the concentration polarization in the bulk solution, (III) a non-quadratic correlation for ICEO of non-Newtonian fluids and attributed it to the power-law viscosity, (IV) an induced-charge electrophoretic (ICEP) rotation of Janus doublets, etc. Furthermore, various ICEK-based micro- and nano-fluidic devices have been developed, namely, micropumps, particle focusers, trappers, sorters, and nanopore ion diodes. The present article provides a comprehensive review on the recent advancement of ICEK. Firstly, the fundamental studies of ICEK are introduced; then the micro- and nano-fluidic applications based on ICEK are presented; lastly, promising future directions for both fundamental and applications are discussed. This review presents the basic framework of ICEK, and can facilitate the development of ICEK-based applications.
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Liu W, Ren Y, Tao Y, Yan H, Xiao C, Wu Q. Buoyancy-Free Janus Microcylinders as Mobile Microelectrode Arrays for Continuous Microfluidic Biomolecule Collection within a Wide Frequency Range: A Numerical Simulation Study. MICROMACHINES 2020; 11:mi11030289. [PMID: 32164333 PMCID: PMC7142959 DOI: 10.3390/mi11030289] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 02/24/2020] [Accepted: 03/09/2020] [Indexed: 11/16/2022]
Abstract
We numerically study herein the AC electrokinetic motion of Janus mobile microelectrode (ME) arrays in electrolyte solution in a wide field frequency, which holds great potential for biomedical applications. A fully coupled physical model, which incorporates the fluid-structure interaction under the synergy of induced-charge electroosmotic (ICEO) slipping and interfacial Maxwell stress, is developed for this purpose. A freely suspended Janus cylinder free from buoyancy, whose main body is made of polystyrene, while half of the particle surface is coated with a thin conducting film of negligible thickness, will react actively on application of an AC signal. In the low-frequency limit, induced-charge electrophoretic (ICEP) translation occurs due to symmetric breaking in ICEO slipping, which renders the insulating end to move ahead. At higher field frequencies, a brand-new electrokinetic transport phenomenon called "ego-dielectrophoresis (e-DEP)" arises due to the action of the localized uneven field on the inhomogeneous particle dipole moment. In stark contrast with the low-frequency ICEP translation, the high-frequency e-DEP force tends to drive the asymmetric dipole moment to move in the direction of the conducting end. The bidirectional transport feature of Janus microspheres in a wide AC frequency range can be vividly interpreted as an array of ME for continuous loading of secondary bioparticles from the surrounding liquid medium along its direction-controllable path by long-range electroconvection. These results pave the way for achieving flexible and high-throughput on-chip extraction of nanoscale biological contents for subsequent on-site bioassay based upon AC electrokinetics of Janus ME arrays.
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Affiliation(s)
- Weiyu Liu
- School of Electronics and Control Engineering, Chang’an University, Middle-Section of Nan’er Huan Road, Xi’an 710064, China; (W.L.); (C.X.); (Q.W.)
| | - Yukun Ren
- State Key Laboratory of Robotics and System, Harbin Institute of Technology, West Da-zhi Street 92, Harbin 150001, China;
- Correspondence: (R.Y.); (H.Y.); Tel.: +86-0451-8641-8028 (Y.R.)
| | - Ye Tao
- State Key Laboratory of Robotics and System, Harbin Institute of Technology, West Da-zhi Street 92, Harbin 150001, China;
| | - Hui Yan
- School of Mechatronics Engineering, Harbin Institute of Technology, West Da-zhi Street 92, Harbin 150001, China
- Correspondence: (R.Y.); (H.Y.); Tel.: +86-0451-8641-8028 (Y.R.)
| | - Congda Xiao
- School of Electronics and Control Engineering, Chang’an University, Middle-Section of Nan’er Huan Road, Xi’an 710064, China; (W.L.); (C.X.); (Q.W.)
| | - Qisheng Wu
- School of Electronics and Control Engineering, Chang’an University, Middle-Section of Nan’er Huan Road, Xi’an 710064, China; (W.L.); (C.X.); (Q.W.)
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Effects of flexibility of conductive plate on efficiency of an induced-charge electrokinetic micro-mixer under constant and time-varying electric fields-A comprehensive parametric study. Chem Eng Sci 2020. [DOI: 10.1016/j.ces.2019.115335] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Dang BV, Hassanzadeh-Barforoushi A, Syed MS, Yang D, Kim SJ, Taylor RA, Liu GJ, Liu G, Barber T. Microfluidic Actuation via 3D-Printed Molds toward Multiplex Biosensing of Cell Apoptosis. ACS Sens 2019; 4:2181-2189. [PMID: 31321976 DOI: 10.1021/acssensors.9b01057] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Multiplexed analysis of biochemical analytes such as proteins, enzymes, and immune products using a microfluidic device has the potential to cut assay time, reduce sample volume, realize high-throughput, and decrease experimental error without compromising sensitivity. Despite these huge benefits, the need for expensive specialized equipment and the complex photolithography fabrication process for the multiplexed devices have, to date, prevented widespread adoption of microfluidic systems. Here, we present a simple method to fabricate a new microfluidic-based multiplexed biosensing device by taking advantage of 3D-printing. The device is an integration of normally closed (NC) microfluidic valving units which offer superior operational flexibility by using PDMS membrane (E ∼ 1-2 MPa) and require minimized energy input (1-5 kPa). To systematically engineer the device, we first report on the geometrical and operational analysis of a single 3D-printed valving unit. Based on the characterization, we introduce a full prototype multiplexed chip comprising several microfluidic valves. The prototype offers-for the first time in a 3D-printed microfluidic device-the capability of on-demand performce of both a sequential and a parallel biochemical assay. As a proof of concept, our device has been used to simultaneously measure the apoptotic activity of 5 different members of the caspase protease enzyme family. In summary, the 3D-printed valving system showcased in this study overcomes traditional bottlenecks of microfabrication, enabling a new class of sophisticated liquid manipulation required in performing multiplexed sensing for biochemical assays.
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Affiliation(s)
- Bac Van Dang
- School of Mechanical and Manufacturing Engineering, Faculty of Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Amin Hassanzadeh-Barforoushi
- School of Mechanical and Manufacturing Engineering, Faculty of Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
- Cancer Division, Garvan Institute of Medical Research/the Kinghorn Cancer Centre, Sydney, New South Wales 2010, Australia
| | - Maira Shakeel Syed
- School of Mechanical and Manufacturing Engineering, Faculty of Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Danting Yang
- Graduate School of Biomedical Engineering, ARC Centre of Excellence in Nanoscale BioPhotonics, Australian Centre for NanoMedicine, Faculty of Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
- Department of Preventative Medicine, Zhejiang Provincial Key Laboratory of Pathological and Physiological Technology, Medical School of Ningbo University, Ningbo, Zhejiang 315211, China
| | - Sung-Jin Kim
- Department of Mechanical Engineering, Konkuk University, Seoul, 05029, Republic of Korea
| | - Robert A. Taylor
- School of Mechanical and Manufacturing Engineering, Faculty of Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Guo-Jun Liu
- Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, New South Wales 2234, Australia
- Discipline of Medical Imaging & Radiation Sciences, Faculty of Medicine and Health, Brain and Mind Centre, University of Sydney, 94 Mallett Street, Camperdown, New South Wales 2050, Australia
| | - Guozhen Liu
- Graduate School of Biomedical Engineering, ARC Centre of Excellence in Nanoscale BioPhotonics, Australian Centre for NanoMedicine, Faculty of Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Tracie Barber
- School of Mechanical and Manufacturing Engineering, Faculty of Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
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Li M, Li D. Nonlinear electrokinetic motion of electrically induced Janus droplets in microchannels. J Colloid Interface Sci 2019; 538:277-285. [DOI: 10.1016/j.jcis.2018.11.102] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 11/26/2018] [Indexed: 12/15/2022]
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9
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Li M, Li D. Microvalve using electrokinetic motion of electrically induced Janus droplet. Anal Chim Acta 2018; 1021:85-94. [DOI: 10.1016/j.aca.2018.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 11/13/2017] [Accepted: 03/05/2018] [Indexed: 01/12/2023]
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Fluid Flow and Mixing Induced by AC Continuous Electrowetting of Liquid Metal Droplet. MICROMACHINES 2017. [PMCID: PMC6190310 DOI: 10.3390/mi8040119] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this work, we proposed a novel design of a microfluidic mixer utilizing the amplified Marangoni chaotic advection induced by alternating current (AC) continuous electrowetting of a metal droplet situated in electrolyte solution, due to the linear and quadratic voltage-dependence of flow velocity at small or large voltages, respectively. Unlike previous researchers exploiting the unidirectional surface stress with direct current (DC) bias at droplet/medium interface for pumping of electrolytes where the resulting flow rate is linearly proportional to the field intensity, dominance of another kind of dipolar flow pattern caused by local Marangoni stress at the drop surface in a sufficiently intense AC electric field is demonstrated by both theoretical analysis and experimental observation, which exhibits a quadratic growth trend as a function of the applied voltage. The dipolar shear stress merely appears at larger voltages and greatly enhances the mixing performance by inducing chaotic advection between the neighboring laminar flow. The mixer design developed herein, on the basis of amplified Marangoni chaotic advection around a liquid metal droplet at larger AC voltages, has great potential for chemical reaction and microelectromechanical systems (MEMS) actuator applications because of generating high-throughput and excellent mixing performance at the same time.
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Yang Q, Loos K. Janus nanoparticles inside polymeric materials: interfacial arrangement toward functional hybrid materials. Polym Chem 2017. [DOI: 10.1039/c6py01795a] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Recent advances and successes in interfacial behavior of Janus NPs at interfaces are summarized, with the hope to motivate additional efforts in the studies of Janus NPs in polymer matrix for the design of functional hybrid nanostructures and devices with engineered, desired and tailored properties for real-life applications.
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Affiliation(s)
- Qiuyan Yang
- Macromolecular Chemistry & New Polymeric Materials
- Zernike Institute for Advanced Materials
- University of Groningen
- 9747 AG Groningen
- The Netherlands
| | - Katja Loos
- Macromolecular Chemistry & New Polymeric Materials
- Zernike Institute for Advanced Materials
- University of Groningen
- 9747 AG Groningen
- The Netherlands
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12
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Li M, Li D. Fabrication and electrokinetic motion of electrically anisotropic Janus droplets in microchannels. Electrophoresis 2016; 38:287-295. [DOI: 10.1002/elps.201600310] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 07/29/2016] [Accepted: 07/30/2016] [Indexed: 01/05/2023]
Affiliation(s)
- Mengqi Li
- Department of Mechanical and Mechatronics Engineering; University of Waterloo; Waterloo Canada
| | - Dongqing Li
- Department of Mechanical and Mechatronics Engineering; University of Waterloo; Waterloo Canada
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13
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Bayati P, Najafi A. Dynamics of two interacting active Janus particles. J Chem Phys 2016; 144:134901. [DOI: 10.1063/1.4944988] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Affiliation(s)
- Parvin Bayati
- Physics Department, University of Zanjan, Zanjan 45371-38791, Iran
| | - Ali Najafi
- Physics Department, University of Zanjan, Zanjan 45371-38791, Iran
- Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
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14
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Feng H, Wong TN. Pair interactions between conducting and non-conducting cylinders under uniform electric field. Chem Eng Sci 2016. [DOI: 10.1016/j.ces.2015.11.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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15
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Onishi S, Tokuda M, Suzuki T, Minami H. Preparation of janus particles with different stabilizers and formation of one-dimensional particle arrays. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:674-678. [PMID: 25541088 DOI: 10.1021/la504535k] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Janus particles with two hemispheres having different stabilizers, a polystyrene (PS) phase stabilized by poly(acrylic acid) (PAA) (PS(PAA)) and a poly(methyl methacrylate) (PMMA) phase stabilized by poly(vinylpyrrolidone) (PVP) (PMMA(PVP)), were synthesized by the solvent-absorbing/releasing method of PS(PAA)/PMMA(PVP) composite particles with a core-shell structure. The PS(PAA)/PMMA(PVP) composite particles were prepared by seeded dispersion polymerization of MMA using PVP as stabilizer in the presence of PS seed particles stabilized by PAA. We also demonstrated the facile formation of the colloidal chains via hydrogen bonding interaction between different stabilizers.
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Affiliation(s)
- Shohei Onishi
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University , Rokko, Nada, Kobe 657-8501, Japan
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Yabu H, Ohshima H, Saito Y. Double-phase-functionalized magnetic Janus polymer microparticles containing TiO2 and Fe2O3 nanoparticles encapsulated in mussel-inspired amphiphilic polymers. ACS APPLIED MATERIALS & INTERFACES 2014; 6:18122-18128. [PMID: 25265162 DOI: 10.1021/am506530s] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Recently, anisotropic colloidal polymeric materials including Janus microparticles, which have two distinct aspects on their surfaces or interiors, have garnered much interest due to their anisotropic alignment and rotational orientation with respect to external electric or magnetic fields. Janus microparticles are also good candidates for pigments in "twisting ball type" electronic paper, which is considered promising for next-generation flexible display devices. We demonstrate here a universal strategy to encapsulate inorganic nanoparticles and to introduce different such inorganic nanoparticles into distinct polymer phases in Janus microparticles. TiO2 and Fe2O3 nanoparticles were separately encapsulated in two different mussel-inspired amphiphilic copolymers, and then organic-inorganic composite Janus microparticles were prepared by simple evaporation of solvent from the dispersion containing the polymer and nanoparticle. These Janus microparticles were observed to rotate quickly in response to applied magnetic fields.
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Affiliation(s)
- Hiroshi Yabu
- Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University , 2-1-1 Katahira, Aoba-Ku, Sendai, To̅hoku, 980-8577, Japan
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Sun XT, Liu M, Xu ZR. Microfluidic fabrication of multifunctional particles and their analytical applications. Talanta 2014; 121:163-77. [DOI: 10.1016/j.talanta.2013.12.060] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 12/20/2013] [Accepted: 12/25/2013] [Indexed: 12/21/2022]
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Yang Q, de Vries MH, Picchioni F, Loos K. A novel method of preparing metallic Janus silica particles using supercritical carbon dioxide. NANOSCALE 2013; 5:10420-10427. [PMID: 24056955 DOI: 10.1039/c3nr81280d] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In this study, we demonstrate a novel fabrication method to prepare metallic Janus silica particles by embedding nanosized silica particles on a spherical polystyrene (PS) substrate in supercritical carbon dioxide (sc CO2), followed by labelling with gold nanoparticles on the exposed part of the silica colloids. To this end, three main types of Janus particles displaying two distinct surfaces are produced by recovering silica from the polystyrene template. Embedment of particles into the PS template in sc CO2 allows for precise control of the degree of embedding of particles and subsequent modification of the partially exposed particle surface. The embedding degree, as well as the final Janus balance, can be varied over a wide range through control of pressure, temperature, or treatment time of sc CO2. Hierarchical PS-silica composites and embedment are evaluated by scanning electron microscopy (SEM). Partial surface modification with gold nanoparticles is investigated by transmission electron microscopy (TEM). With this method various functionalized Janus particles with tuneable properties can be prepared by adjusting various surface modifiers and polymer substrates in the future.
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Affiliation(s)
- Qiuyan Yang
- Department of Polymer Chemistry, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
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Numerical study of a novel induced-charge electrokinetic micro-mixer. Anal Chim Acta 2013; 763:28-37. [DOI: 10.1016/j.aca.2012.12.010] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Revised: 09/27/2012] [Accepted: 12/04/2012] [Indexed: 11/23/2022]
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20
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Daghighi Y, Sinn I, Kopelman R, Li D. Experimental validation of induced-charge electrokinetic motion of electrically conducting particles. Electrochim Acta 2013. [DOI: 10.1016/j.electacta.2012.09.021] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Wang YN, Yang RJ, Ju WJ, Wu MC, Fu LM. Convenient quantification of methanol concentration detection utilizing an integrated microfluidic chip. BIOMICROFLUIDICS 2012; 6:34111. [PMID: 23940501 PMCID: PMC3432083 DOI: 10.1063/1.4746246] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 07/31/2012] [Indexed: 05/23/2023]
Abstract
A rapid and simple technique is proposed for methanol concentration detection using a PMMA (Polymethyl-Methacrylate) microfluidic chip patterned using a commercially available CO2 laser scriber. In the proposed device, methanol and methanol oxidase (MOX) are injected into a three-dimensional circular chamber and are mixed via a vortex stirring effect. The mixture is heated to prompt the formation of formaldehyde and is flowed into a rectangular chamber, to which fuchsin-sulphurous acid is then added. Finally, the microchip is transferred to a UV spectrophotometer for methanol detection purposes. The experimental results show that a correlation coefficient of R(2) = 0.9940 is obtained when plotting the optical density against the methanol concentration for samples and an accuracy as high as 93.1% are compared with the determined by the high quality gas chromatography with concentrations in the range of 2 ∼ 100 ppm. The methanol concentrations of four commercial red wines are successfully detected using the developed device. Overall, the results show that the proposed device provides a rapid and accurate means of detecting the methanol concentration for a variety of applications in the alcoholic beverage inspection and control field.
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Affiliation(s)
- Yao-Nan Wang
- Department of Vehicle Engineering, National Pingtung University of Science and Technology, Pingtung 912, Taiwan
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