1
|
Chen D, Huang Q, Ni Z, Xiang N. Particle focusing mechanisms in λ-DNA solution flowing in a straight microchannel. Electrophoresis 2024; 45:1379-1388. [PMID: 38343171 DOI: 10.1002/elps.202300295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 01/27/2024] [Accepted: 02/03/2024] [Indexed: 08/22/2024]
Abstract
Most biological fluids (such as blood, saliva, and lymph) in nature have certain viscoelasticity and are beginning to be used as the carrying fluids for viscoelastic microfluidics. However, the particle-focusing mechanisms in these new biological viscoelastic fluids are still unclear. In this work, the particle-focusing mechanisms in λ-DNA solutions were systematically explored. We first explored the particle focusing dynamics in a square cross-section under varied flow rates to uncover the effects of flow rate on particle focusing. Three focusing stages, from the classic five-position viscoelastic focusing to single-stream focusing and finally to multiplex-stream focusing, were clearly demonstrated. In addition, the particle focusing process along the channel length was demonstrated, and a first-fast-and-then-slow focusing process was clearly observed. Then, the effects of λ-DNA concentrations on particle focusing were explored and compared using the solutions with 0-25 ppm λ-DNA. Finally, we discussed the inferences of blockage ratio on particle focusing by changing the particle diameter and cross-sectional dimensions. Our work may provide a deeper understanding on the particle focusing mechanisms in biological viscoelastic fluids and lays a foundation for the subsequent particle counting and analysis and the development of low-cost portable flow cytometers.
Collapse
Affiliation(s)
- Dalin Chen
- School of Mechanical Engineering, and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, P. R. China
| | - Qiang Huang
- School of Mechanical Engineering, and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, P. R. China
| | - Zhonghua Ni
- School of Mechanical Engineering, and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, P. R. China
| | - Nan Xiang
- School of Mechanical Engineering, and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, P. R. China
| |
Collapse
|
2
|
Nasir Ahamed NN, Mendiola-Escobedo CA, Perez-Gonzalez VH, Lapizco-Encinas BH. Manipulating the insulating post arrangement in DC-biased AC-iEK devices to improve microparticle separations. Analyst 2024; 149:2469-2479. [PMID: 38516870 DOI: 10.1039/d3an02160b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
There is a growing interest in the advancement of microscale electrokinetic (EK) systems for biomedical and clinical applications, as these systems offer attractive characteristics such as portability, robustness, low sample requirements and short response time. The present work is focused on manipulating the characteristics of the insulating post arrangement in insulator-based EK (iEK) systems for separating a binary mixture of spherical microparticles with same diameter (5.1 μm), same shape, made from the same substrate material and only differing in their zeta potential by ∼14 mV. This study presents a combination of mathematical modeling and experimental separations performed by applying a low-frequency alternating current (AC) voltage in iEK systems with 12 distinct post arrangements. These iEK devices were used to systematically study the effect of three spatial characteristics of the insulating post array on particle separations: the horizontal separation and the vertical separation between posts, and introducing an offset to the posts arrangement. Through normalization of the spatial separation between the insulating posts with respect to particle diameter, guidelines to improve separation resolution for different particle mixtures possessing similar characteristics were successfully identified. The results indicated that by carefully designing the spatial arrangement of the post array, separation resolution values in the range of 1.4-2.8 can be obtained, illustrating the importance and effect of the arrangement of insulating posts on improving particle separations. This study demonstrates that iEK devices, with effectively designed spatial arrangement of the insulating post arrays, have the capabilities to perform discriminatory separations of microparticles of similar characteristics.
Collapse
Affiliation(s)
- Nuzhet Nihaar Nasir Ahamed
- Microscale Bioseparations Laboratory and Biomedical Engineering Department, Rochester Institute of Technology, 160 Lomb Memorial Drive, Rochester, New York, 14623, USA.
| | | | - Victor H Perez-Gonzalez
- School of Engineering and Sciences, Tecnologico de Monterrey, Monterrey, Nuevo Leon 64849, Mexico.
| | - Blanca H Lapizco-Encinas
- Microscale Bioseparations Laboratory and Biomedical Engineering Department, Rochester Institute of Technology, 160 Lomb Memorial Drive, Rochester, New York, 14623, USA.
| |
Collapse
|
3
|
Tabarhoseini SM, Bentor J, Johnson W, Tzeng TR, Xuan X. Effects of Tween 20 addition on electrokinetic transport in a polydimethylsiloxane microchannel. Electrophoresis 2024. [PMID: 38509871 DOI: 10.1002/elps.202400024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/07/2024] [Accepted: 03/12/2024] [Indexed: 03/22/2024]
Abstract
Tween 20 is frequently added to particle suspensions for reducing the particle-wall adhesion and particle-particle aggregation in microfluidic devices. However, the influences of Tween 20 on the fluid and particle behaviors have been largely ignored. We present in this work the first experimental study of the effects of Tween 20 addition on the electrokinetic transport of fluids and particles in a polydimethylsiloxane microchannel. We find that adding 0.1% v/v Tween 20 to a buffer solution can significantly reduce the electroosmotic mobility as well as the electrokinetic and electrophoretic mobilities of polystyrene particles and yeast cells. Further increasing the Tween 20 concentration within the range typically used in microfluidic applications continues reducing these mobility values, but at a smaller rate. Our finding suggests that Tween 20 should be used with care in electrokinetic microdevices when the flow rate or particle/cell throughput is an important parameter.
Collapse
Affiliation(s)
| | - Joseph Bentor
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA
| | - Walter Johnson
- Department of Biological Sciences, Clemson University, Clemson, South Carolina, USA
| | - Tzuen-Rong Tzeng
- Department of Biological Sciences, Clemson University, Clemson, South Carolina, USA
| | - Xiangchun Xuan
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA
| |
Collapse
|
4
|
Bentor J, Xuan X. Particle Size-Dependent Electrophoresis in Polymer Solutions. Anal Chem 2024. [PMID: 38321932 DOI: 10.1021/acs.analchem.3c05655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
It has long been known that the electrophoretic velocity of a charged particle is independent of its size under the thin-Debye-layer limit. This so-called Smoluchowski velocity is, however, valid only for Newtonian fluids. A couple of recent theoretical studies predict the rheology-induced particle size dependence of electrophoresis in non-Newtonian fluids. This work presents the first experimental demonstration of such dependence in viscoelastic poly(ethylene oxide) (PEO) solutions. Three different-sized particles are observed to travel at the same electrophoretic velocity in a Newtonian buffer through a rectangular microchannel. In contrast, their measured electrophoretic velocities in the PEO solution exhibit an increasing trend for larger particles, which is consistent with theoretical prediction. This particle size dependence is found to grow with an increasing concentration or length of the PEO polymer. Both trends are attributed to enhanced fluid elasticity, as characterized by the increasing elasticity number.
Collapse
Affiliation(s)
- Joseph Bentor
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina 29634-0921, United States
| | - Xiangchun Xuan
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina 29634-0921, United States
| |
Collapse
|
5
|
Raihan MK, Baghdady M, Dort H, Bentor J, Xuan X. Fluid Elasticity-Enhanced Insulator-Based Dielectrophoresis for Sheath-Free Particle Focusing in Very Dilute Polymer Solutions. Anal Chem 2023; 95:16013-16020. [PMID: 37856245 DOI: 10.1021/acs.analchem.3c03311] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
Focusing particles into a narrow stream is usually a necessary step in microfluidic flow cytometry and particle sorting. We demonstrate that the addition of a small amount of poly(ethylene oxide) (PEO) polymer into a buffer solution can reduce by almost 1 order of magnitude the threshold DC electric field for single-line dielectrophoretic focusing of particles in a constricted microchannel. The particle focusing effectiveness of this fluid elasticity-enhanced insulator-based dielectrophoresis (E-iDEP) in very dilute PEO solutions gets enhanced with the increase of the PEO molecular weight and particle size. These two trends are consistent with a theoretical analysis that accounts for the fluid elasticity effects on the electrokinetic and dielectrophoretic particle motions. Surprisingly, the particle-focusing effectiveness of E-iDEP is observed to first increase and then decrease with an increase in the PEO concentration.
Collapse
Affiliation(s)
- Mahmud Kamal Raihan
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Micah Baghdady
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Heston Dort
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Joseph Bentor
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Xiangchun Xuan
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina 29634, United States
| |
Collapse
|
6
|
Shi L, Zhong X, Wu T, Bian Q, Liu X, Miao H, Deng Y, Yin B, Zhou T. The electrodynamics of rod‐like microparticles based on optically induced dielectrophoresis. Electrophoresis 2022; 43:2175-2183. [DOI: 10.1002/elps.202200102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 09/03/2022] [Accepted: 09/06/2022] [Indexed: 11/07/2022]
Affiliation(s)
- Liuyong Shi
- Mechanical and Electrical Engineering College Hainan University Haikou P. R. China
| | - Xiangtao Zhong
- Mechanical and Electrical Engineering College Hainan University Haikou P. R. China
| | - Tao Wu
- Mechanical and Electrical Engineering College Hainan University Haikou P. R. China
| | - Qin Bian
- Mechanical and Electrical Engineering College Hainan University Haikou P. R. China
| | - Xiaomei Liu
- Mechanical and Electrical Engineering College Hainan University Haikou P. R. China
| | - Huaqing Miao
- Shenzhen Academy of Metrology & Quality Inspection Shenzhen P. R. China
| | - Yongbo Deng
- Changchun Institute of Optics Fine Mechanics and Physics (CIOMP) Chinese Academy of Science Changchun P. R. China
| | - Binfeng Yin
- School of Mechanical Engineering Yangzhou University Yangzhou P. R. China
| | - Teng Zhou
- Mechanical and Electrical Engineering College Hainan University Haikou P. R. China
| |
Collapse
|
7
|
Yin S, Huang Y, Li H, Wong TN. Dynamics of alternating current electric field–assisted non‐Newtonian droplet formation with geometry confinement. Electrophoresis 2022; 43:2120-2129. [DOI: 10.1002/elps.202200056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 04/06/2022] [Accepted: 04/22/2022] [Indexed: 11/11/2022]
Affiliation(s)
- Shuai Yin
- School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore Singapore
| | - Yi Huang
- School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore Singapore
- Research Institute of Aero‐Engine Beihang University Beijing P. R. China
| | - Haiwang Li
- Research Institute of Aero‐Engine Beihang University Beijing P. R. China
| | - Teck Neng Wong
- School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore Singapore
| |
Collapse
|
8
|
Afsaneh H, Mohammadi R. Microfluidic platforms for the manipulation of cells and particles. TALANTA OPEN 2022. [DOI: 10.1016/j.talo.2022.100092] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
|
9
|
Mahapatra B, Bandopadhyay A. Effect of skimming layer in an electroosmotically driven viscoelastic fluid flow over charge modulated walls. Electrophoresis 2021; 43:724-731. [PMID: 34748645 DOI: 10.1002/elps.202100221] [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: 07/16/2021] [Revised: 10/20/2021] [Accepted: 10/26/2021] [Indexed: 02/04/2023]
Abstract
We report a numerical study on the effect of the skimming layer in an EOF of Oldroyd-B fluid over charge modulated walls. Three types of flow conditions were identified on the basis of the relative thickness of the skimming layer and the electrical double layer. We observe maximum slip velocity magnitude when the skimming layer thickness is very less than the thickness of the electrical double layer. For higher skimming layer thickness compared to the thickness of electrical double layer, slip velocity magnitude attenuates, and the polymeric stress inside the skimming layer becomes zero. Enhanced fluid elasticity generates asymmetric flow structures inside the microchannel, which can also be achieved by imposing an asymmetric surface charge along the channel walls. Our present analysis highlights the complex flow dynamics of the EOF of biofluids/polymeric fluids with a near-wall region depleted of macro-molecules.
Collapse
Affiliation(s)
- Bimalendu Mahapatra
- Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India
| | - Aditya Bandopadhyay
- Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India
| |
Collapse
|
10
|
Bentor J, Raihan MK, McNeely C, Liu Z, Song Y, Xuan X. Fluid rheological effects on streaming dielectrophoresis in a post-array microchannel. Electrophoresis 2021; 43:717-723. [PMID: 34657307 DOI: 10.1002/elps.202100270] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 10/06/2021] [Accepted: 10/12/2021] [Indexed: 11/06/2022]
Abstract
Recent studies have demonstrated the strong influences of fluid rheological properties on insulator-based dielectrophoresis (iDEP) in single-constriction microchannels. However, it is yet to be understood how iDEP in non-Newtonian fluids depends on the geometry of insulating structures. We report in this work an experimental study of fluid rheological effects on streaming DEP in a post-array microchannel that presents multiple contractions and expansions. The iDEP focusing and trapping of particles in a viscoelastic polyethylene oxide solution are comparable to those in a Newtonian buffer, which is consistent with the observations in a single-constriction microchannel. Similarly, the insignificant iDEP effects in a shear-thinning xanthan gum solution also agree with those in the single-constriction channel except that gel-like structures are observed to only form in the post-array microchannel under large DC electric fields. In contrast, the iDEP effects in both viscoelastic and shear-thinning polyacrylamide solution are significantly weaker than in the single-constriction channel. Moreover, instabilities occur in the electroosmotic flow and appear to be only dependent on the DC electric field. These phenomena may be associated with the dynamics of polymers as they are electrokinetically advected around and through the posts.
Collapse
Affiliation(s)
- Joseph Bentor
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA
| | - Mahmud Kamal Raihan
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA
| | - Colin McNeely
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA
| | - Zhijian Liu
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA.,College of Marine Engineering, Dalian Maritime University, Dalian, P. R. China
| | - Yongxin Song
- College of Marine Engineering, Dalian Maritime University, Dalian, P. R. China
| | - Xiangchun Xuan
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA
| |
Collapse
|
11
|
Dixit A, Parashar CK, Dutta S, Mahanta J, Kakati N, Bandyopadhyay D. A microfluidic viscometer: Translation of oscillatory motion of a water microdroplet in oil under electric field. Electrophoresis 2021; 42:2162-2170. [PMID: 34342881 DOI: 10.1002/elps.202100152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 07/29/2021] [Accepted: 07/31/2021] [Indexed: 11/07/2022]
Abstract
The electric field induced motion of a charged water droplet suspended in a low-dielectric oil medium is exploited to evaluate the rheological properties of the suspending medium. The time-periodic electrophoretic motion of the droplet between the electrodes decorated in a polymeric micro-well is translated into a proof-of-concept microfluidic prototype, which can measure viscosities of the unknown fluid samples. The variations in the instantaneous velocities of the migrating droplet have been measured inside silicone oil of known physical properties at different electric field intensities. Subsequently, a balance between the electric field to the viscous force has been employed to evaluate the experimental charge density on the droplet surface. Thereafter, a comprehensive scaling law has been devised to find a correlation between the charge on the droplet to the dielectric permittivity of the surrounding medium, size of the water droplet, and the applied electric field intensity. Following this, the scaling law and force balance have been employed together to evaluate the unknown viscosity of an array of suspending mediums by simply analyzing the electrophoretic motion of water droplet. The model proposed is also found to be consistent when a solid amberlite microparticle has been employed as a probe instead of the water droplet. In such a scenario, minor changes in the exponents of the scaling law are found to be necessary to reproduce the results obtained using the water droplet. The method paves the way for the making of an economical and portable microfluidic rheometer with further finetuning and translational developments.
Collapse
Affiliation(s)
- Anvesh Dixit
- Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati, India
| | | | - Satarupa Dutta
- Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati, India
| | - Jiwajyoti Mahanta
- Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati, India
| | - Nayanjyoti Kakati
- Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati, India
| | - Dipankar Bandyopadhyay
- Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati, India.,Centre for Nanotechnology, Indian Institute of Technology Guwahati, Guwahati, India
| |
Collapse
|