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Britel A, Tomagra G, Aprà P, Varzi V, Sturari S, Amine NH, Olivero P, Picollo F. 3D printing in microfluidics: experimental optimization of droplet size and generation time through flow focusing, phase, and geometry variation. RSC Adv 2024; 14:7770-7778. [PMID: 38444974 PMCID: PMC10913413 DOI: 10.1039/d4ra00752b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 02/26/2024] [Indexed: 03/07/2024] Open
Abstract
Droplet-based microfluidics systems have become widely used in recent years thanks to their advantages, varying from the possibility of handling small fluid volumes to directly synthesizing and encapsulating various living forms for biological-related applications. The effectiveness of such systems mainly depends on the ability to control some of these systems' parameters, such as produced droplet size and formation time, which represents a challenging task. This work reports an experimental study on tuning droplet size and generation time in a flow-focusing geometry fabricated with stereolithography 3D printing by exploring the interplay of phase and geometrical parameters. We produced droplets at different low flow rates of continuous and dispersed phases to assess the effect of each of these phases on the droplets' size and formation time. We observed that smaller droplets were produced for high viscosity oil and water phase, along with high flow rates. In addition, changing the microfluidics channels' width, and morphology of the orifice has shown a similar effect on droplet size, as shown in the case of high-viscosity solutions. The variation of the bifurcation angle shows a noticeable variation in terms of the achieved droplet size and formation time. We further investigated the impact of modifying the width ratio of the continuous and dispersed phases on droplet formation.
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Affiliation(s)
- Adam Britel
- Department of Physics, "NIS" Inter-departmental Centre, University of Torino, National Institute of Nuclear Physics Sect. Torino, Via Pietro Giuria 1 10125 Torino Italy
| | - Giulia Tomagra
- Department of Drug and Science Technology, NIS Interdepartmental Centre, University of Torino Corso Raffaello 30 10125 Torino Italy
| | - Pietro Aprà
- Department of Physics, "NIS" Inter-departmental Centre, University of Torino, National Institute of Nuclear Physics Sect. Torino, Via Pietro Giuria 1 10125 Torino Italy
| | - Veronica Varzi
- Department of Physics, "NIS" Inter-departmental Centre, University of Torino, National Institute of Nuclear Physics Sect. Torino, Via Pietro Giuria 1 10125 Torino Italy
| | - Sofia Sturari
- Department of Physics, "NIS" Inter-departmental Centre, University of Torino, National Institute of Nuclear Physics Sect. Torino, Via Pietro Giuria 1 10125 Torino Italy
| | - Nour-Hanne Amine
- Department of Physics, "NIS" Inter-departmental Centre, University of Torino, National Institute of Nuclear Physics Sect. Torino, Via Pietro Giuria 1 10125 Torino Italy
| | - Paolo Olivero
- Department of Physics, "NIS" Inter-departmental Centre, University of Torino, National Institute of Nuclear Physics Sect. Torino, Via Pietro Giuria 1 10125 Torino Italy
| | - Federico Picollo
- Department of Physics, "NIS" Inter-departmental Centre, University of Torino, National Institute of Nuclear Physics Sect. Torino, Via Pietro Giuria 1 10125 Torino Italy
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2
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Mirkale K, Jain SK, Oviya TS, Mahalingam S. Optomicrofluidic detection of cancer cells in peripheral blood via metabolic glycoengineering. Lab Chip 2023; 23:5151-5164. [PMID: 37955355 DOI: 10.1039/d3lc00678f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2023]
Abstract
The currently existing label-based techniques for the detection of circulating tumor cells (CTCs) target natural surface proteins of cells and are therefore applicable to only limited cancer cell types. We report optomicrofluidic detection of cancer cells in the pool of peripheral blood mononuclear cells (PBMCs) by exploiting the difference in their cell metabolism. We employ metabolic glycoengineering as a click chemistry tool for tagging cells that yields several fold-higher fluorescence signals from cancer cells compared to that from PBMCs. The effects of concentrations of the tagging compounds and cell incubation time on the fluorescence signal intensity are studied. The tagged cells were encapsulated in droplets ensuring that cells enter the detection region two-dimensionally focused in single-file and optically detected with a high detection efficiency and low coefficient of variation of the signals. The metabolic tagging approach showed a significantly higher tagging efficiency and average fluorescence signal compared to the well-established and widely adopted anti-EpCAM-FITC-based tagging. We demonstrated the detection of three different cancer cell lines - EpCAM-negative cervical cancer cell, HeLa, weakly EpCAM positive, and triple-negative breast cancer cell, MDA-MB-231, and strongly EpCAM positive breast cancer cell, MCF7, highlighting that the proposed technique is independent of naturally occurring cell surface proteins and widely applicable. The metabolically tagged and optically detected cells were successfully recultured, proving the compatibility of the proposed technique with downstream assays. The proposed technique is then utilised for the detection of CTCs in metastatic cancer patients' blood. The current work provides a new strategy for detecting cancer cells in the blood that can find potential applications in both fundamental research and clinical studies involving CTCs as well as in single-cell sequencing.
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Affiliation(s)
- K Mirkale
- Micro Nano Bio Fluidics Unit, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai-600036, Tamilnadu, India.
| | - S K Jain
- Micro Nano Bio Fluidics Unit, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai-600036, Tamilnadu, India.
| | - T S Oviya
- Micro Nano Bio Fluidics Unit, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai-600036, Tamilnadu, India.
| | - S Mahalingam
- Laboratory of Molecular Cell Biology, National Cancer Tissue Biobank, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai-600036, India
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3
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Pandian K, Matsui M, Hankemeier T, Ali A, Okubo-Kurihara E. Advances in single-cell metabolomics to unravel cellular heterogeneity in plant biology. Plant Physiol 2023; 193:949-965. [PMID: 37338502 PMCID: PMC10517197 DOI: 10.1093/plphys/kiad357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 05/03/2023] [Accepted: 05/17/2023] [Indexed: 06/21/2023]
Abstract
Single-cell metabolomics is a powerful tool that can reveal cellular heterogeneity and can elucidate the mechanisms of biological phenomena in detail. It is a promising approach in studying plants, especially when cellular heterogeneity has an impact on different biological processes. In addition, metabolomics, which can be regarded as a detailed phenotypic analysis, is expected to answer previously unrequited questions which will lead to expansion of crop production, increased understanding of resistance to diseases, and in other applications as well. In this review, we will introduce the flow of sample acquisition and single-cell techniques to facilitate the adoption of single-cell metabolomics. Furthermore, the applications of single-cell metabolomics will be summarized and reviewed.
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Affiliation(s)
- Kanchana Pandian
- Metabolomics and Analytics Centre, Leiden Academic Centre for Drug Research, Leiden University, Einstein Road 55, 2333 CC Leiden, The Netherlands
| | - Minami Matsui
- RIKEN, Center for Sustainable Resource Science, Kanagawa 230-0045, Japan
| | - Thomas Hankemeier
- Metabolomics and Analytics Centre, Leiden Academic Centre for Drug Research, Leiden University, Einstein Road 55, 2333 CC Leiden, The Netherlands
| | - Ahmed Ali
- Metabolomics and Analytics Centre, Leiden Academic Centre for Drug Research, Leiden University, Einstein Road 55, 2333 CC Leiden, The Netherlands
| | - Emiko Okubo-Kurihara
- RIKEN, Center for Sustainable Resource Science, Kanagawa 230-0045, Japan
- College of Science, Rikkyo University, Tokyo 171-8501, Japan
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4
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Silva DPF, Coelho RCV, da Gama MMT, Araújo NAM. Effect of droplet deformability on shear thinning in a cylindrical channel. Phys Rev E 2023; 107:035106. [PMID: 37073003 DOI: 10.1103/physreve.107.035106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 02/28/2023] [Indexed: 04/20/2023]
Abstract
Droplets suspended in fluids flowing through microchannels are often encountered in different contexts and scales, from oil extraction down to microfluidics. They are usually flexible and deform as a product of the interplay between flexibility, hydrodynamics, and interaction with confining walls. Deformability adds distinct characteristics to the nature of the flow of these droplets. We simulate deformable droplets suspended in a fluid at a high volume fraction flowing through a cylindrical wetting channel. We find a discontinuous shear thinning transition, which depends on the droplet deformability. The capillary number is the main dimensionless parameter that controls the transition. Previous results have focused on two-dimensional configurations. Here we show that, in three dimensions, even the velocity profile is different. To perform this study, we improve and extend to three dimensions a multicomponent lattice Boltzmann method which prevents the coalescence between the droplets.
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Affiliation(s)
- Danilo P F Silva
- Centro de Física Teórica e Computacional, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal and Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Rodrigo C V Coelho
- Centro de Física Teórica e Computacional, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal and Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Margarida M Telo da Gama
- Centro de Física Teórica e Computacional, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal and Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Nuno A M Araújo
- Centro de Física Teórica e Computacional, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal and Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
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5
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Abstract
Interfacial migration of droplets in microfluidic confinements has significant relevance in cell biology and biochemical assays. So far, studies on passive interfacial migration of droplets are limited to co-flow interfaces having small interfacial tension (IFT ∼ 1 mN/m). Here, we elucidate the migration and spreading of droplets (SiO-1000, SiO-100, FC40, and castor oil as phase 3, P3) across the interface between a pair of coflowing streams (PEG as P1, SiO-100, SiO-20, FC40, and olive oil as P2) having large IFT (∼10 mN/m), with the three different phases immiscible. Interfacial migration involving interfaces of large IFT is facilitated by confining droplets between the channel wall and coflow interface. We find that contact between droplets and the coflow interface is governed by the confinement ratio (i.e., the ratio of drop size to stream width) and the ratio of the capillary numbers of the coflowing streams. Depending on the sign of the spreading parameter (S) of the co-flowing phases, droplet migration or spreading at the interface is observed. While interfacial migration is observed for S1 < 0 and S2 > 0, droplet spreading is observed for S1 < 0 and S2 < 0, where S1 and S2 are P1 and P2 side spreading parameters, respectively. We investigate the droplet migration dynamics and time evolution of the contact line and the interface. Our results show that the speed of interfacial migration increases with increasing spreading parameter contrast between the coflowing phases. In the droplet spreading case, we experimentally study the variation in the spreading length with time, revealing three distinct regimes in good agreement with predictions from analytical scaling. Our study explores the interfacial transport of droplets involving high IFT interfaces, advancing the fundamental understanding of the topic that may find relevance in droplet microfluidics.
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Affiliation(s)
- Shamik Hazra
- Fluid Systems Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai, 600036 Tamilnadu, India
| | - Sushanta Mitra
- Waterloo Institute for Nanotechnology, Department of Mechanical & Mechatronics Engineering, University of Waterloo, Waterloo, N2L 3G1 Ontario, Canada
| | - Ashis Kumar Sen
- Fluid Systems Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai, 600036 Tamilnadu, India
- Micro Nano Bio-Fluidics Group, Indian Institute of Technology Madras, Chennai, 600036 Tamilnadu, India
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6
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Banerjee U, Jain SK, Sen AK. Particle encapsulation in aqueous ferrofluid drops and sorting of particle-encapsulating drops from empty drops using a magnetic field. Soft Matter 2021; 17:6020-6028. [PMID: 34060567 DOI: 10.1039/d1sm00530h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Handling and manipulation of particle-encapsulating droplets (PED) have profound applications in biochemical assays. Herein we report encapsulation of microparticles in aqueous ferrofluid droplets in a primary continuous phase (CP) and sorting of PED from empty droplets (ED) at the interface of the CP in coflow with a second continuous phase using a magnetic field. We find that the encapsulation process results in a size contrast between the PED and ED that depends on the flow regime - squeezing, dripping, or jetting - which in turn is governed by the ratio of the discrete phase to the continuous phase capillary number, Car. The difference between the volume fractions of ferrofluid in the PED and ED, ΔαPED, is utilized for sorting, and is found to depend on the ratio of the capillary numbers, Car. The difference ΔαPED is found to be maximum in the jetting regime, suggesting that the jetting regime is most suitable for encapsulation and sorting. The sorting criterion is represented in terms of a parameter ξ, which is a function of the ratios of the magnetic force to the interfacial force experienced by the PED and ED. Our study revealed that sorting is possible for ξ < 0, which corresponds to ΔαPED > 0.25. The maximum sorting efficiency of our system is found to be ∼95% at a throughput of ∼100 drops per s.
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Affiliation(s)
- U Banerjee
- Micro Nano Bio-Fluidics Unit, Fluid Systems Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai-600036, India.
| | - S K Jain
- Micro Nano Bio-Fluidics Unit, Fluid Systems Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai-600036, India.
| | - A K Sen
- Micro Nano Bio-Fluidics Unit, Fluid Systems Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai-600036, India.
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Yang Y, Wang Z, Chen R, Zhu X, Liao Q, Ye D, Yang Y, Li W. Droplet Migration and Coalescence in a Microchannel Induced by the Photothermal Effect of a Focused Infrared Laser. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.0c05550] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Yijing Yang
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400030, China
- Institute of Engineering Thermophysics, School of Energy and Power Engineering, Chongqing University, Chongqing 400030, China
| | - Zhibin Wang
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400030, China
- Institute of Engineering Thermophysics, School of Energy and Power Engineering, Chongqing University, Chongqing 400030, China
| | - Rong Chen
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400030, China
- Institute of Engineering Thermophysics, School of Energy and Power Engineering, Chongqing University, Chongqing 400030, China
| | - Xun Zhu
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400030, China
- Institute of Engineering Thermophysics, School of Energy and Power Engineering, Chongqing University, Chongqing 400030, China
| | - Qiang Liao
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400030, China
- Institute of Engineering Thermophysics, School of Energy and Power Engineering, Chongqing University, Chongqing 400030, China
| | - Dingding Ye
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400030, China
- Institute of Engineering Thermophysics, School of Energy and Power Engineering, Chongqing University, Chongqing 400030, China
| | - Yang Yang
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400030, China
- Institute of Engineering Thermophysics, School of Energy and Power Engineering, Chongqing University, Chongqing 400030, China
| | - Wei Li
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400030, China
- Institute of Engineering Thermophysics, School of Energy and Power Engineering, Chongqing University, Chongqing 400030, China
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Abstract
Single-cell analysis has emerged as a powerful method for genomics, transcriptomics, proteomics, and metabolomics characterisation at the individual cell level. Here, we demonstrate a technique for the detection and selective isolation of target cells encapsulated in microdroplets in single-cell format. A sample containing a mixed population of cells with fluorescently labelled target cells can be focused using a sheath fluid to direct cells in single file toward a droplet junction, wherein the cells are encapsulated inside droplets. The droplets containing the cells migrate toward the centre of the channel owing to non-inertial lift force. The cells present in the droplets are studied and characterised based on forward scatter (FSC), side scatter (SSC), and fluorescence (FL) signals. The FL signals from the target cells can be used to activate a selective isolation module based on electro-coalescence, using suitable electronics and a program to sort droplets containing the target cells in single-cell format from droplets containing background cells. We demonstrated the detection and isolation of target cells (cancer cells: HeLa and DU145) from mixed populations of cells, peripheral blood mononuclear cells (PBMC) + cervical cancer cells (HeLa) and PBMC + human prostate cancer cells (DU145), at a concentration range of 104-106 ml-1 at 300 cells per s. The performance of the device is characterised in terms of sorting efficiency (>97%), enrichment (>1800×), purity (>98%), and recovery (>95%). The sorted target cells were found to be viable (>95% viability) and showed good proliferation when cultured, showing the potential of the proposed sorting technique for downstream analysis.
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Affiliation(s)
- R Gaikwad
- Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai-600036, India.
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9
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Abstract
The manipulation of aqueous droplets has a profound significance in biochemical assays. Magnetic field-driven droplet manipulation, offering unique advantages, is consequently gaining attention. However, the phenomenon relating to diamagnetic droplets is not well understood. Here, we report the understanding of trapping and coalescence of flowing diamagnetic aqueous droplets in a paramagnetic (oil-based ferrofluid) medium using negative magnetophoresis. Our study revealed that the trapping phenomenon is underpinned by the interplay of magnetic energy (Em) and frictional (viscous) energy (Ef), in terms of magnetophoretic stability number, Sm = (Em/Ef). The trapping and nontrapping regimes are characterized based on the peak value of magnetophoretic stability number, Smp, and droplet size, D*. The study of coalescence of a trapped droplet with a follower droplet (and a train of droplets) revealed that the film-drainage Reynolds number (Refd) representing the coalescence time depends on the magnetic Bond number, Bom. The coalesced droplet continues to remain trapped or gets self-released obeying the Smp and D* criterion. Our study offers an understanding of the magnetic manipulation of diamagnetic aqueous droplets that can potentially be used for biochemical assays in microfluidics.
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Affiliation(s)
- S K Jain
- Micro Nano Bio-Fluidics Unit, Fluid Systems Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, India
| | - U Banerjee
- Micro Nano Bio-Fluidics Unit, Fluid Systems Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, India
| | - A K Sen
- Micro Nano Bio-Fluidics Unit, Fluid Systems Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, India
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Hazra S, Mitra SK, Sen AK. Lateral migration of viscoelastic droplets in a viscoelastic confined flow: role of discrete phase viscoelasticity. Soft Matter 2019; 15:9003-9010. [PMID: 31675049 DOI: 10.1039/c9sm01469a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The cross-stream motion of viscoelastic droplets in viscoelastic fluids has received little attention since the classical study of migration of drops in a second order fluid. In this work, going beyond the existing classical theory, we experimentally elucidate the effect of drop-to-medium viscosity ratio k and elasticity ratio ξ on wall and center migration of viscoelastic droplets in a Poiseuille flow of a viscoelastic medium (PVP) at low Reynolds numbers (Re ≪ 1). We observed a contrasting migration behavior of Newtonian and viscoelastic droplets having the same viscosity ratios and propose the presence of a lift force FVD due to the viscoelasticity of the droplet phase. We use analytical scaling and empirical modelling to show that the force FVD scales with a prefactor that depends upon the Weissenberg number WiD and drop-to-medium viscosity ratio k and elasticity ratio ξ. Further, we utilize the proposed force for sorting of viscoelastic and Newtonian droplets.
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Affiliation(s)
- Shamik Hazra
- Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai-600036, India.
| | - Sushanta K Mitra
- Waterloo Institute for Nanotechnology, University of Waterloo, Ontario N2L 3G1, Canada
| | - Ashis Kumar Sen
- Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai-600036, India.
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11
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Pitt WG, Alizadeh M, Blanco R, Hunter AK, Bledsoe CG, McClellan DS, Wood ME, Wood RL, Ravsten TV, Hickey CL, Cameron Beard W, Stepan JR, Carter A, Husseini GA, Robison RA, Welling E, Torgesen RN, Anderson CM. Factors affecting sedimentational separation of bacteria from blood. Biotechnol Prog 2019; 36:e2892. [PMID: 31425635 DOI: 10.1002/btpr.2892] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 06/19/2019] [Accepted: 08/01/2019] [Indexed: 12/18/2022]
Abstract
Rapid diagnosis of blood infections requires fast and efficient separation of bacteria from blood. We have developed spinning hollow disks that separate bacteria from blood cells via the differences in sedimentation velocities of these particles. Factors affecting separation included the spinning speed and duration, and disk size. These factors were varied in dozens of experiments for which the volume of separated plasma, and the concentration of bacteria and red blood cells (RBCs) in separated plasma were measured. Data were correlated by a parameter of characteristic sedimentation length, which is the distance that an idealized RBC would travel during the entire spin. Results show that characteristic sedimentation length of 20 to 25 mm produces an optimal separation and collection of bacteria in plasma. This corresponds to spinning a 12-cm-diameter disk at 3,000 rpm for 13 s. Following the spin, a careful deceleration preserves the separation of cells from plasma and provides a bacterial recovery of about 61 ± 5%.
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Affiliation(s)
- William G Pitt
- Chemical Engineering Department, Brigham Young University, Provo, Utah
| | - Mahsa Alizadeh
- Chemical Engineering Department, Brigham Young University, Provo, Utah
| | - Rae Blanco
- Chemical Engineering Department, Brigham Young University, Provo, Utah
| | - Alex K Hunter
- Chemical Engineering Department, Brigham Young University, Provo, Utah
| | - Colin G Bledsoe
- Chemical Engineering Department, Brigham Young University, Provo, Utah
| | | | - Madison E Wood
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah
| | - Ryan L Wood
- Chemical Engineering Department, Brigham Young University, Provo, Utah
| | - Tanner V Ravsten
- Chemical Engineering Department, Brigham Young University, Provo, Utah
| | - Caroline L Hickey
- Chemical Engineering Department, Brigham Young University, Provo, Utah
| | | | - Jacob R Stepan
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah
| | - Alexandra Carter
- Chemical Engineering Department, Brigham Young University, Provo, Utah
| | - Ghaleb A Husseini
- Chemical Engineering Department, American University of Sharjah, Sharjah, United Arab Emirates
| | - Richard A Robison
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah
| | - Evelyn Welling
- Chemical Engineering Department, Brigham Young University, Provo, Utah
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12
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Mandal C, Banerjee U, Sen AK. Transport of a Sessile Aqueous Droplet over Spikes of Oil Based Ferrofluid in the Presence of a Magnetic Field. Langmuir 2019; 35:8238-8245. [PMID: 31141667 DOI: 10.1021/acs.langmuir.9b00631] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Droplets can be used as carrier vehicles for the transportation of biological and chemical reagents. Manipulation of water- and oil-based ferromagnetic droplets in the presence of a magnetic field has been well-studied. Here, we elucidate the transport of a sessile aqueous (diamagnetic) droplet placed over spikes of oil-based ferrofluid (FF) in the presence of a nonuniform magnetic field. An oil-based FF droplet, dispensed over a rigid oleophilic surface, interacts with a magnetic field to get transformed into an array of spikes which then act as a carrier for the transportation of the aqueous droplet. Our study reveals that transportation phenomena is governed by the interplay of three different forces: magnetic force Fm, frictional force Ff, and interfacial tension force Fi, which is expressed in terms of the magnetic Laplace number ( Lam) and magnetic Bond number ( Bom) as Lam?1 = ( Ff1/ Fm, x) and Bom Lam?1 = ( Ff2/ Fi). Based on the values of the dimensionless numbers, three different regimes, steady droplet transport, spike extraction, and magnet disengagement, are identified. It is found that steady droplet transport is observed for Lam?1 ? 1 and Bom Lam?1 ? 1, whereas extraction of spikes is observed for Lam?1 ? 1 and Bom Lam?1 > 1 and magnet disengagement is observed for Lam?1 > 1. In the steady droplet transport regime, velocity of the aqueous droplet Uds was found to be dependent on the volumes of the aqueous droplet Vw and FF droplet VFF following Uds ? Vw?0.19 VFF0.36. A simple model is presented that accurately predicts the aqueous droplet velocity Uds within 5% of the corresponding experimental data. In the spike extraction regime, the spike extraction distance Lse was found to vary with Vw, VFF, and the magnet velocity Ums following Lse ? Vw?1.75 VFF0.75 Ums?1.56.
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Affiliation(s)
- C Mandal
- Department of Mechanical Engineering , Indian Institute of Technology Madras , Chennai - 600036 , India
| | - U Banerjee
- Department of Mechanical Engineering , Indian Institute of Technology Madras , Chennai - 600036 , India
| | - A K Sen
- Department of Mechanical Engineering , Indian Institute of Technology Madras , Chennai - 600036 , India
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13
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Jayaprakash KS, Sen AK. Droplet encapsulation of particles in different regimes and sorting of particle-encapsulating-droplets from empty droplets. Biomicrofluidics 2019; 13:034108. [PMID: 31123540 PMCID: PMC6517185 DOI: 10.1063/1.5096937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 04/29/2019] [Indexed: 05/17/2023]
Abstract
Encapsulation of microparticles in droplets has profound applications in biochemical assays. We investigate encapsulation of rigid particles (polystyrene beads) and deformable particles (biological cells) inside aqueous droplets in various droplet generation regimes, namely, squeezing, dripping, and jetting. Our study reveals that the size of the positive (particle-encapsulating) droplets is larger or smaller compared to that of the negative (empty) droplets in the dripping and jetting regimes but no size contrast is observed in the squeezing regime. The size contrast of the positive and negative droplets in the different regimes is characterized in terms of capillary number C a and stream width ratio ω (i.e., ratio of stream width at the throat to particle diameter ω = w / d p ). While for deformable particles, the positive droplets are always larger compared to the negative droplets, for rigid particles, the positive droplets are larger in the dripping and jetting regimes for 0.50 ≤ ω ≤ 0.80 but smaller in the jetting regime for ω < 0.50 . We exploit the size contrast of positive and negative droplets for sorting across the fluid-fluid interface based on noninertial lift force (at R e ≪ 1 ), which is a strong function of droplet size. We demonstrate sorting of the positive droplets encapsulating polystyrene beads and biological cells from the negative droplets with an efficiency of ∼95% and purity of ∼65%. The proposed study will find relevance in single-cell studies, where positive droplets need to be isolated from the empty droplets prior to downstream processing.
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Affiliation(s)
- K. S. Jayaprakash
- Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, India
| | - A. K. Sen
- Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, India
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Hemachandran E, Karthick S, Laurell T, Sen AK. Relocation of coflowing immiscible liquids under acoustic field in a microchannel. ACTA ACUST UNITED AC 2019. [DOI: 10.1209/0295-5075/125/54002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
Double emulsions are often used as containers to perform high throughput screening assays and as templates for capsules. These applications require double emulsions to be mechanically stable such that they do not coalesce during processing and storage. A possibility to increase their stability is to reduce the thickness of their shells to sufficiently low values that lubrication effects hinder coalescence. However, the controlled fabrication of double emulsions with such thin shells is difficult. Here, we introduce a new microfluidic device, the aspiration device, that reduces the shell thickness of double emulsions down to 240 nm at a high throughput; thereby, the shell volume is reduced by up to 95%. The shell thickness of the resulting double emulsions depends on the pressure profile in the device and hence on the fluid flow rates in the channels and is independent of the shell thickness of the injected double emulsions. Therefore, this device enables converting double emulsions with polydisperse shell thicknesses into double emulsions with well-defined, uniform thin shells.
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Affiliation(s)
- A Vian
- Soft Materials Laboratory, Institute of Materials, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
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Raj A, Sen AK. Entry and passage behavior of biological cells in a constricted compliant microchannel. RSC Adv 2018; 8:20884-20893. [PMID: 35542327 PMCID: PMC9080859 DOI: 10.1039/c8ra02763c] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 05/28/2018] [Indexed: 11/30/2022] Open
Abstract
We report an experimental and theoretical investigation of the entry and passage behaviour of biological cells (HeLa and MDA-MB-231) in a constricted compliant microchannel. Entry of a cell into a micro-constriction takes place in three successive regimes: protrusion and contact (cell protrudes its leading edge and makes a contact with the channel wall), squeeze (cell deforms to enter into the constriction) and release (cell starts moving forward). While the protrusion and contact regime is insensitive to the flexibility of the channel, the squeeze zone is significantly smaller in the case of a more compliant channel. Similarly, in the release zone, the acceleration of the cells into the microconstriction is higher in the case of a more compliant channel. The results showed that for a fixed size ratio ρ and E c, the extension ratio λ decreases and transit velocity U c increases with increase in the compliance parameter f p. The variation in the cell velocity is governed by force due to the cell stiffness F s as well as that due to the viscous dampening F d, explained using the Kelvin-Voigt viscoelastic model. The entry time t e = m(ρ) k 1 (1 + f p) k 2 (E c) k 3 and induced hydrodynamic resistance of a cell ΔR c/R = k(ρ) a (1 + k f f p) b (k E E c) c were correlated with cell size ratio ρ, Young's modulus E c and compliance parameter f p, which showed that both entry time t e and the induced hydrodynamic resistance ΔR c are most sensitive to the change in the compliance parameter f p. This study provides understanding of the passage of cells in compliant micro-confinements that can have significant impact on mechanophenotyping of single cells.
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Affiliation(s)
- A Raj
- Department of Mechanical Engineering, Indian Institute of Technology Madras Chennai-600036 India
| | - A K Sen
- Department of Mechanical Engineering, Indian Institute of Technology Madras Chennai-600036 India
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Zhang L, Liu Z, Pang Y, Wang X, Li M, Ren Y. Trapping a moving droplet train by bubble guidance in microfluidic networks. RSC Adv 2018; 8:8787-8794. [PMID: 35539830 PMCID: PMC9078607 DOI: 10.1039/c7ra13507f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 02/21/2018] [Indexed: 12/20/2022] Open
Abstract
Trapping a train of moving droplets into preset positions within a microfluidic device facilitates the long-term observation of biochemical reactions inside the droplets. In this paper, a new bubble-guided trapping method, which can remarkably improve the limited narrow two-phase flow rate range of uniform trapping, was proposed by taking advantage of the unique physical property that bubbles do not coalescence with two-phase fluids and the hydrodynamic characteristic of large flow resistance of bubbles. The flow behaviors of bubble-free and bubble-guided droplet trains were compared and analyzed under the same two-phase flow rates. The experimental results show that the droplets trapped by bubble-free guided trapping exhibit the four trapping modes of sequentially uniform trapping, non-uniform trapping induced by break-up and collision, and failed trapping due to squeezing through, and the droplets exhibit the desired uniform trapping in a relatively small two-phase flow rate range. Compared with bubble-free guided droplets, bubble-guided droplets also show four trapping modes. However, the two-phase flow rate range in which uniform trapping occurs is increased significantly and the uniformity of the trapped droplet array is improved. This investigation is beneficial to enhance the applicability of microfluidic chips for storing droplets in a passive way.
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Affiliation(s)
- Longxiang Zhang
- College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology Beijing 100124 China
| | - Zhaomiao Liu
- College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology Beijing 100124 China
| | - Yan Pang
- College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology Beijing 100124 China
| | - Xiang Wang
- College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology Beijing 100124 China
| | - Mengqi Li
- College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology Beijing 100124 China
| | - Yanlin Ren
- College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology Beijing 100124 China
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Jayaprakash KS, Sen AK. Continuous splitting of aqueous droplets at the interface of co-flowing immiscible oil streams in a microchannel. Soft Matter 2018; 14:725-733. [PMID: 29349475 DOI: 10.1039/c7sm02068f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report the continuous splitting of aqueous droplets at the interface between two co-flowing immiscible oil streams in a microchannel. The aqueous droplets initially present in a primary continuous stream (CP1) migrate into a secondary continuous stream (CP2) when the ratio of the non-inertial lift force to the interfacial tension force exceeds a critical value (K. S. Jayaprakash, U. Banerjee and A. K. Sen, Langmuir, 2016, 32, 2136-2143). Here, experiments were performed to understand the droplet splitting phenomenon and demonstrate the splitting of droplets encapsulating microbeads and cells. The results showed that the droplet splitting phenomenon is governed by the capillary number Ca, which is a function of the average shear stress across the channel, interfacial tension σ between the CP1 and the droplet phase and the droplet length-scale L. Irrespective of the individual values of these parameters, droplet splitting was observed when the capillary number Ca exceeds a critical value Cacr, which was found to be a function of droplet to CP2 viscosity ratio λ. The Cacr was found to be minimum for λ ≈ 1 but higher for droplets of λ ≫ 1 and λ ≪ 1. The sizes of the primary and secondary daughter and migrated droplets (i.e. Lp|sD and Lp|sM) were found to increase linearly with the increase in the size of the primary or secondary parent droplets (Lp|sP). Splitting of parent droplets encapsulating a single microbead or PBMC showed that after splitting, the presence of the microbead or PBMC in the daughter or migrated droplets depends on the ratio of the size of the migrated droplets to that of the parent droplet (i.e. VM/VP). Finally, splitting of parent droplets containing two or more microbeads or cells into droplets containing a single particle or cell was demonstrated. A new paradigm of droplet splitting is reported that could find applications in soft matter and single-cell studies.
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Affiliation(s)
- K S Jayaprakash
- Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai, 600036, India.
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Raj A, Dixit M, Doble M, Sen AK. A combined experimental and theoretical approach towards mechanophenotyping of biological cells using a constricted microchannel. Lab Chip 2017; 17:3704-3716. [PMID: 28983550 DOI: 10.1039/c7lc00599g] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
We report a combined experimental and theoretical technique that enables the characterization of various mechanical properties of biological cells. The cells were infused into a microfluidic device that comprises multiple parallel micro-constrictions to eliminate device clogging and facilitate characterization of cells of different sizes and types on a single device. The extension ratio λ and transit velocity Uc of the cells were measured using high-speed and high-resolution imaging which were then used in a theoretical model to predict the Young's modulus Ec = f(λ, Uc) of the cells. The predicted Young's modulus Ec values for three different cell lines (182 ± 34.74 Pa for MDA MB 231, 360 ± 75 Pa for MCF 10A and, 763 ± 93 Pa for HeLa) compare well with those reported in the literature from micropipette measurements and atomic force microscopy measurement within 10% and 15%, respectively. Also, the Young's modulus of MDA-MB-231 cells treated with 50 μM 4-hyrdroxyacetophenone (for localization of myosin II) for 30 min was found out to be 260 ± 52 Pa. The entry time te of cells into the micro-constrictions was predicted using the model and validated using experimentally measured data. The entry and transit behaviors of cells in the micro-constriction including cell deformation (extension ratio λ) and velocity Uc were experimentally measured and used to predict various cell properties such as the Young's modulus, cytoplasmic viscosity and induced hydrodynamic resistance of different types of cells. The proposed combined experimental and theoretical approach leads to a new paradigm for mechanophenotyping of biological cells.
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Affiliation(s)
- A Raj
- Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai-600036, India.
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Jayaprakash KS, Banerjee U, Sen AK. Dynamics of rigid microparticles at the interface of co-flowing immiscible liquids in a microchannel. J Colloid Interface Sci 2017; 493:317-326. [PMID: 28119242 DOI: 10.1016/j.jcis.2017.01.034] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 01/07/2017] [Accepted: 01/10/2017] [Indexed: 11/16/2022]
Abstract
We report the dynamical migration behavior of rigid polystyrene microparticles at an interface of co-flowing streams of primary CP1 (aqueous) and secondary CP2 (oils) immiscible phases at low Reynolds numbers (Re) in a microchannel. The microparticles initially suspended in the CP1 either continue to flow in the bulk CP1 or migrate across the interface into CP2, when the stream width of the CP1 approaches the diameter of the microparticles. Experiments were performed with different secondary phases and it is found that the migration criterion depends on the sign of the spreading parameter S and the presence of surfactant at the interface. To substantiate the migration criterion, experiments were also carried out by suspending the microparticles in CP2 (oil phase). Our study reveals that in case of aqueous-silicone oil combination, the microparticles get attached to the interface since S<0 and the three phase contact angle, θ>90°. For complete detachment of microparticles from the interface into the secondary phase, additional energy ΔG is needed. We discuss the role of interfacial perturbation, which causes detachment of microparticles from the interface. In case of mineral and olive oils, the surfactants present at the interface prevents attachment of the microparticles to the interface due to the repulsive disjoining pressure. Finally, using a aqueous-silicone oil system, we demonstrate size based sorting of microparticles of size 25μm and 15μm respectively from that of 15μm and 10μm and study the variation of separation efficiency η with the ratio of the width of the aqueous stream to the diameter of the microparticles ρ.
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Affiliation(s)
- K S Jayaprakash
- Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, India
| | - U Banerjee
- Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, India
| | - A K Sen
- Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, India.
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Abstract
Here, we demonstrate a novel method of measurement which determines precisely the hydrodynamic resistance of a droplet flowing through a channel. The obtained results show that the hydrodynamic resistance of a droplet in a microchannel achieves its maximum for lengths of the droplet ranging from 3w to 4w and that interactions between beads in a train exist.
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Affiliation(s)
- Slawomir Jakiela
- Department of Biophysics, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland.
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Jayaprakash KS, Banerjee U, Sen AK. Dynamics of Aqueous Droplets at the Interface of Coflowing Immiscible Oils in a Microchannel. Langmuir 2016; 32:2136-43. [PMID: 26812441 DOI: 10.1021/acs.langmuir.5b04116] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report the dynamics of aqueous droplets of different size and viscosity at the interface of a coflowing stream of immiscible oils (i.e., primary and secondary continuous phases) in a microchannel, at low Re. The lateral migration of droplets introduced into the primary continuous phase toward the interface and subsequent selective migration of droplets across the interface into the secondary continuous phase is investigated. The interplay between the competing noninertial lift and interfacial tension forces, which govern the interfacial migration of the droplets, is presented and discussed. The velocity and strain rate profiles, and interface location, which are critical for calculating the lift force and migration behavior of droplets, are presented. The trajectories of droplets of different size and viscosity in the primary continuous phase are obtained for different interface locations. During interfacial migration, the deformation behavior of droplets of different viscosities is studied. Finally, sorting of droplets based on size contrast is demonstrated and sorting efficiency is found. A new paradigm of migration and sorting of droplets is reported, which could find importance in chemical and biological applications.
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Affiliation(s)
- K S Jayaprakash
- Department of Mechanical Engineering, Indian Institute of Technology Madras , Chennai-600036, India
| | - U Banerjee
- Department of Mechanical Engineering, Indian Institute of Technology Madras , Chennai-600036, India
| | - A K Sen
- Department of Mechanical Engineering, Indian Institute of Technology Madras , Chennai-600036, India
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Abstract
This paper reports the characterization and sorting of cells based on stiffness contrast. A microfluidic device with focusing and spacing control for stiffness based sorting of cells is designed, fabricated and demonstrated.
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Affiliation(s)
- P. Sajeesh
- Department of Mechanical Engineering
- Indian Institute of Technology Madras
- Chennai-600036
- India
| | - A. Raj
- Department of Mechanical Engineering
- Indian Institute of Technology Madras
- Chennai-600036
- India
| | - M. Doble
- Department of Biotechnology
- Indian Institute of Technology Madras
- Chennai-600036
- India
| | - A. K. Sen
- Department of Mechanical Engineering
- Indian Institute of Technology Madras
- Chennai-600036
- India
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Maria MS, Kumar BS, Chandra TS, Sen AK. Development of a microfluidic device for cell concentration and blood cell-plasma separation. Biomed Microdevices 2015; 17. [DOI: 10.1007/s10544-015-0017-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Sajeesh P, Manasi S, Doble M, Sen AK. A microfluidic device with focusing and spacing control for resistance-based sorting of droplets and cells. Lab Chip 2015; 15:3738-3748. [PMID: 26235533 DOI: 10.1039/c5lc00598a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This paper reports a novel hydrodynamic technique for sorting of droplets and cells based on size and deformability. The device comprises two modules: a focusing and spacing control module and a sorting module. The focusing and spacing control module enables focusing of objects present in a sample onto one of the side walls of a channel with controlled spacing between them using a sheath fluid. A 3D analytical model is developed to predict the sheath-to-sample flow rate ratio required to facilitate single-file focusing and maintain the required spacing between a pair of adjacent objects. Experiments are performed to demonstrate focusing and spacing control of droplets (size 5-40 μm) and cells (HL60, size 10-25 μm). The model predictions compare well with experimental data in terms of focusing and spacing control within 9%. In the sorting module, the main channel splits into two branch channels (straight and side branches) with the flow into these two channels separated by a "dividing streamline". A sensing channel and a bypass channel control the shifting of the dividing streamline depending on the object size and deformability. While resistance offered by individual droplets of different sizes has been studied in our previous work (P. Sajeesh, M. Doble and A. K. Sen, Biomicrofluidics, 2014, 8, 1-23), here we present resistance of individual cells (HL60) as a function of size. A theoretical model is developed and used for the design of the sorter. Experiments are performed for size-based sorting of droplets (sizes 25 and 40 μm, 10 and 15 μm) and HL60 cells (sizes 11 μm and 19 μm) and deformability-based sorting of droplets (size 10 ± 1.0 μm) and polystyrene microbeads (size 10 ± 0.2 μm). The performance of the device for size- and deformability-based sorting is characterized in terms of sorting efficiency. The proposed device could be potentially used as a diagnostic tool for sorting of larger tumour cells from smaller leukocytes.
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Affiliation(s)
- P Sajeesh
- Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, India.
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Surya HPN, Parayil S, Banerjee U, Chander S, Sen AK. Alternating and merged droplets in a double T-junction microchannel. BioChip J 2014. [DOI: 10.1007/s13206-014-9103-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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