1
|
Moraes da Silva Junior S, Bento Ribeiro LE, Fruett F, Stiens J, Swart JW, Moshkalev S. A Novel Microfluidics Droplet-Based Interdigitated Ring-Shaped Electrode Sensor for Lab-on-a-Chip Applications. MICROMACHINES 2024; 15:672. [PMID: 38930642 PMCID: PMC11205656 DOI: 10.3390/mi15060672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Revised: 05/14/2024] [Accepted: 05/16/2024] [Indexed: 06/28/2024]
Abstract
This paper presents a comprehensive study focusing on the detection and characterization of droplets with volumes in the nanoliter range. Leveraging the precise control of minute liquid volumes, we introduced a novel spectroscopic on-chip microsensor equipped with integrated microfluidic channels for droplet generation, characterization, and sensing simultaneously. The microsensor, designed with interdigitated ring-shaped electrodes (IRSE) and seamlessly integrated with microfluidic channels, offers enhanced capacitance and impedance signal amplitudes, reproducibility, and reliability in droplet analysis. We were able to make analyses of droplet length in the range of 1.0-6.0 mm, velocity of 0.66-2.51 mm/s, and volume of 1.07 nL-113.46 nL. Experimental results demonstrated that the microsensor's performance is great in terms of droplet size, velocity, and length, with a significant signal amplitude of capacitance and impedance and real-time detection capabilities, thereby highlighting its potential for facilitating microcapsule reactions and enabling on-site real-time detection for chemical and biosensor analyses on-chip. This droplet-based microfluidics platform has great potential to be directly employed to promote advances in biomedical research, pharmaceuticals, drug discovery, food engineering, flow chemistry, and cosmetics.
Collapse
Affiliation(s)
- Salomão Moraes da Silva Junior
- Electronics & Informatics, Vrije Universiteit of Brussel, 1050 Brussels, Belgium
- Center for Semiconductor Components and Nanotechnologies, State University of Campinas, Campinas 13083-852, Brazil;
- School of Electrical and Computer Engineering, State University of Campinas, Campinas 13083-852, Brazil (J.W.S.)
- BioSense Institute, University of Novi Sad, 21000 Novi Sad, Serbia
| | - Luiz Eduardo Bento Ribeiro
- School of Electrical and Computer Engineering, State University of Campinas, Campinas 13083-852, Brazil (J.W.S.)
| | - Fabiano Fruett
- School of Electrical and Computer Engineering, State University of Campinas, Campinas 13083-852, Brazil (J.W.S.)
| | - Johan Stiens
- Electronics & Informatics, Vrije Universiteit of Brussel, 1050 Brussels, Belgium
| | - Jacobus Willibrordus Swart
- School of Electrical and Computer Engineering, State University of Campinas, Campinas 13083-852, Brazil (J.W.S.)
| | - Stanislav Moshkalev
- Center for Semiconductor Components and Nanotechnologies, State University of Campinas, Campinas 13083-852, Brazil;
| |
Collapse
|
2
|
He Y, Qiao Y, Ding L, Cheng T, Tu J. Recent advances in droplet sequential monitoring methods for droplet sorting. BIOMICROFLUIDICS 2023; 17:061501. [PMID: 37969470 PMCID: PMC10645479 DOI: 10.1063/5.0173340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 10/23/2023] [Indexed: 11/17/2023]
Abstract
Droplet microfluidics is an attractive technology to run parallel experiments with high throughput and scalability while maintaining the heterogeneous features of individual samples or reactions. Droplet sorting is utilized to collect the desired droplets based on droplet characterization and in-droplet content evaluation. A proper monitoring method is critical in this process, which governs the accuracy and maximum frequency of droplet handling. Until now, numerous monitoring methods have been integrated in the microfluidic devices for identifying droplets, such as optical spectroscopy, mass spectroscopy, electrochemical monitoring, and nuclear magnetic resonance spectroscopy. In this review, we summarize the features of various monitoring methods integrated into droplet sorting workflow and discuss their suitable condition and potential obstacles in use. We aim to provide a systematic introduction and an application guide for choosing and building a droplet monitoring platform.
Collapse
Affiliation(s)
- Yukun He
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Yi Qiao
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Lu Ding
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Tianguang Cheng
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Jing Tu
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| |
Collapse
|
3
|
Monserrat Lopez D, Rottmann P, Puebla-Hellmann G, Drechsler U, Mayor M, Panke S, Fussenegger M, Lörtscher E. Direct electrification of silicon microfluidics for electric field applications. MICROSYSTEMS & NANOENGINEERING 2023; 9:81. [PMID: 37342556 PMCID: PMC10277806 DOI: 10.1038/s41378-023-00552-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 04/25/2023] [Accepted: 05/10/2023] [Indexed: 06/23/2023]
Abstract
Microfluidic systems are widely used in fundamental research and industrial applications due to their unique behavior, enhanced control, and manipulation opportunities of liquids in constrained geometries. In micrometer-sized channels, electric fields are efficient mechanisms for manipulating liquids, leading to deflection, injection, poration or electrochemical modification of cells and droplets. While PDMS-based microfluidic devices are used due to their inexpensive fabrication, they are limited in terms of electrode integration. Using silicon as the channel material, microfabrication techniques can be used to create nearby electrodes. Despite the advantages that silicon provides, its opacity has prevented its usage in most important microfluidic applications that need optical access. To overcome this barrier, silicon-on-insulator technology in microfluidics is introduced to create optical viewports and channel-interfacing electrodes. More specifically, the microfluidic channel walls are directly electrified via selective, nanoscale etching to introduce insulation segments inside the silicon device layer, thereby achieving the most homogeneous electric field distributions and lowest operation voltages feasible across microfluidic channels. These ideal electrostatic conditions enable a drastic energy reduction, as effectively shown via picoinjection and fluorescence-activated droplet sorting applications at voltages below 6 and 15 V, respectively, facilitating low-voltage electric field applications in next-generation microfluidics.
Collapse
Affiliation(s)
- Diego Monserrat Lopez
- IBM Research Europe - Zurich, Säumerstrasse 4, CH-8803 Rüschlikon, Switzerland
- ETH Zürich, Department of Biosystems Science and Engineering, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Philipp Rottmann
- ETH Zürich, Department of Biosystems Science and Engineering, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Gabriel Puebla-Hellmann
- IBM Research Europe - Zurich, Säumerstrasse 4, CH-8803 Rüschlikon, Switzerland
- University of Basel, Department of Chemistry, St. Johanns-Ring 19, CH-4056 Basel, Switzerland
| | - Ute Drechsler
- IBM Research Europe - Zurich, Säumerstrasse 4, CH-8803 Rüschlikon, Switzerland
| | - Marcel Mayor
- University of Basel, Department of Chemistry, St. Johanns-Ring 19, CH-4056 Basel, Switzerland
- Institute for Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), P. O. Box 3640, 76021 Karlsruhe, Germany
| | - Sven Panke
- ETH Zürich, Department of Biosystems Science and Engineering, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Martin Fussenegger
- ETH Zürich, Department of Biosystems Science and Engineering, Mattenstrasse 26, 4058 Basel, Switzerland
- University of Basel, Faculty of Life Science, Basel, Switzerland
| | - Emanuel Lörtscher
- IBM Research Europe - Zurich, Säumerstrasse 4, CH-8803 Rüschlikon, Switzerland
| |
Collapse
|
4
|
Ali M, Park J. Ultrasonic surface acoustic wave-assisted separation of microscale droplets with varying acoustic impedance. ULTRASONICS SONOCHEMISTRY 2023; 93:106305. [PMID: 36706667 PMCID: PMC9938309 DOI: 10.1016/j.ultsonch.2023.106305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 01/15/2023] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
In droplet-based microfluidic platforms, precise separation of microscale droplets of different chemical composition is increasingly necessary for high-throughput combinatorial chemistry in drug discovery and screening assays. A variety of droplet sorting methods have been proposed, in which droplets of the same kind are translocated. However, there has been relatively less effort in developing techniques to separate the uniform-sized droplets of different chemical composition. Most of the previous droplet sorting or separation techniques either rely on the droplet size for the separation marker or adopt on-demand application of a force field for the droplet sorting or separation. The existing droplet microfluidic separation techniques based on the in-droplet chemical composition are still in infancy because of the technical difficulties. In this study, we propose an acoustofluidic method to simultaneously separate microscale droplets of the same volume and dissimilar acoustic impedance using ultrasonic surface acoustic wave (SAW)-induced acoustic radiation force (ARF). For extensive investigation on the SAW-induced ARF acting on both cylindrical and spherical droplets, we first performed a set of the droplet sorting experiments under varying conditions of acoustic impedance of the dispersed phase fluid, droplet velocity, and wave amplitude. Moreover, for elucidation of the underlying physics, a new dimensionless number ARD was introduced, which was defined as the ratio of the ARF to the drag force acting on the droplets. The experimental results were comparatively analyzed by using a ray acoustics approach and found to be in good agreement with the theoretical estimation. Based on the findings, we successfully demonstrated the simultaneous separation of uniform-sized droplets of the different acoustic impedance under continuous application of the acoustic field in a label-free and detection-free manner. Insomuch as on-chip, precise separation of multiple kinds of droplets is critical in many droplet microfluidic applications, the proposed acoustofluidic approach will provide new prospects for microscale droplet separation.
Collapse
Affiliation(s)
- Mushtaq Ali
- Department of Mechanical Engineering, Chonnam National University, Yongbong-ro 77, Buk-gu, Gwangju 61186, Republic of Korea
| | - Jinsoo Park
- Department of Mechanical Engineering, Chonnam National University, Yongbong-ro 77, Buk-gu, Gwangju 61186, Republic of Korea.
| |
Collapse
|
5
|
Huang C, Jiang Y, Li Y, Zhang H. Droplet Detection and Sorting System in Microfluidics: A Review. MICROMACHINES 2022; 14:mi14010103. [PMID: 36677164 PMCID: PMC9867185 DOI: 10.3390/mi14010103] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/23/2022] [Accepted: 12/26/2022] [Indexed: 05/26/2023]
Abstract
Since being invented, droplet microfluidic technologies have been proven to be perfect tools for high-throughput chemical and biological functional screening applications, and they have been heavily studied and improved through the past two decades. Each droplet can be used as one single bioreactor to compartmentalize a big material or biological population, so millions of droplets can be individually screened based on demand, while the sorting function could extract the droplets of interest to a separate pool from the main droplet library. In this paper, we reviewed droplet detection and active sorting methods that are currently still being widely used for high-through screening applications in microfluidic systems, including the latest updates regarding each technology. We analyze and summarize the merits and drawbacks of each presented technology and conclude, with our perspectives, on future direction of development.
Collapse
Affiliation(s)
- Can Huang
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 77842, USA
| | - Yuqian Jiang
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Yuwen Li
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 77842, USA
| | - Han Zhang
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 77842, USA
| |
Collapse
|
6
|
Yang H, Knowles TPJ. Hydrodynamics of Droplet Sorting in Asymmetric Acute Junctions. MICROMACHINES 2022; 13:1640. [PMID: 36295993 PMCID: PMC9611150 DOI: 10.3390/mi13101640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/16/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
Droplet sorting is one of the fundamental manipulations of droplet-based microfluidics. Although many sorting methods have already been proposed, there is still a demand to develop new sorting methods for various applications of droplet-based microfluidics. This work presents numerical investigations on droplet sorting with asymmetric acute junctions. It is found that the asymmetric acute junctions could achieve volume-based sorting and velocity-based sorting. The pressure distributions in the asymmetric junctions are discussed to reveal the physical mechanism behind the droplet sorting. The dependence of the droplet sorting on the droplet volume, velocity, and junction angle is explored. The possibility of the employment of the proposed sorting method in most real experiments is also discussed. This work provides a new, simple, and cost-effective passive strategy to separate droplets in microfluidic channels. Moreover, the proposed acute junctions could be used in combination with other sorting methods, which may boost more opportunities to sort droplets.
Collapse
Affiliation(s)
- He Yang
- School of Mechanical Engineering, Hangzhou Dianzi University, No. 2 Street, Qiantang District, Hangzhou 310018, China
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Tuomas P. J. Knowles
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, UK
| |
Collapse
|
7
|
Dhar P, Paul A. Hydrodynamics of electro-capillarity propelled non-Newtonian droplets through micro-confinements. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2022; 45:38. [PMID: 35467174 PMCID: PMC9035497 DOI: 10.1140/epje/s10189-022-00196-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
In this article, we theoretically explore the dynamics of droplet motion and its evolution during electro-capillarity propelled actuation within microfluidic systems. The study covers a wide gamut of fluids, wherein we investigate the dynamics of both pseudoplastic and dilatant fluid droplets. It is observed that change in the fluid rheology of the non-Newtonian fluids leads to significant morphing of the droplet dynamics during the actuation and propulsion event when compared to the Newtonian counterparts. We validate the theory using experimental reports on similar systems employing Newtonian droplets. The influence of governing parameters such as the actuation voltage and its transients, dielectric layer thickness on the electrodes and electrode spacing is probed. We also explore the influence of the interfacial properties of the system, such as channel wall friction, droplet wettability, and capillary friction, and establish that the fluid rheology, in conjunction with the interfacial features regulate the electro-actuation and propulsion of the droplets. We further provide theoretical estimates on the optimal design of the electro-actuation system in terms of a proposed electro-interfacial tension parameter. The findings may hold significance towards design and development of microfluidics with electro-actuation systems.
Collapse
Affiliation(s)
- Purbarun Dhar
- Hydrodynamics and Thermal Multiphysics Lab (HTML), Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India.
| | - Arkadeep Paul
- Department of Mechanical Engineering, National Institute of Technology Durgapur, Durgapur, West Bengal, 713209, India
| |
Collapse
|
8
|
Molloy A, Harrison J, McGrath JS, Owen Z, Smith C, Liu X, Li X, Cox JAG. Microfluidics as a Novel Technique for Tuberculosis: From Diagnostics to Drug Discovery. Microorganisms 2021; 9:microorganisms9112330. [PMID: 34835455 PMCID: PMC8618277 DOI: 10.3390/microorganisms9112330] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/01/2021] [Accepted: 11/03/2021] [Indexed: 12/29/2022] Open
Abstract
Tuberculosis (TB) remains a global healthcare crisis, with an estimated 5.8 million new cases and 1.5 million deaths in 2020. TB is caused by infection with the major human pathogen Mycobacterium tuberculosis, which is difficult to rapidly diagnose and treat. There is an urgent need for new methods of diagnosis, sufficient in vitro models that capably mimic all physiological conditions of the infection, and high-throughput drug screening platforms. Microfluidic-based techniques provide single-cell analysis which reduces experimental time and the cost of reagents, and have been extremely useful for gaining insight into monitoring microorganisms. This review outlines the field of microfluidics and discusses the use of this novel technique so far in M. tuberculosis diagnostics, research methods, and drug discovery platforms. The practices of microfluidics have promising future applications for diagnosing and treating TB.
Collapse
Affiliation(s)
- Antonia Molloy
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK; (A.M.); (J.H.)
| | - James Harrison
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK; (A.M.); (J.H.)
| | - John S. McGrath
- Sphere Fluidics Limited, The McClintock Building, Suite 7, Granta Park, Great Abington, Cambridge CB21 6GP, UK; (J.S.M.); (Z.O.); (C.S.); (X.L.); (X.L.)
| | - Zachary Owen
- Sphere Fluidics Limited, The McClintock Building, Suite 7, Granta Park, Great Abington, Cambridge CB21 6GP, UK; (J.S.M.); (Z.O.); (C.S.); (X.L.); (X.L.)
| | - Clive Smith
- Sphere Fluidics Limited, The McClintock Building, Suite 7, Granta Park, Great Abington, Cambridge CB21 6GP, UK; (J.S.M.); (Z.O.); (C.S.); (X.L.); (X.L.)
| | - Xin Liu
- Sphere Fluidics Limited, The McClintock Building, Suite 7, Granta Park, Great Abington, Cambridge CB21 6GP, UK; (J.S.M.); (Z.O.); (C.S.); (X.L.); (X.L.)
| | - Xin Li
- Sphere Fluidics Limited, The McClintock Building, Suite 7, Granta Park, Great Abington, Cambridge CB21 6GP, UK; (J.S.M.); (Z.O.); (C.S.); (X.L.); (X.L.)
| | - Jonathan A. G. Cox
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK; (A.M.); (J.H.)
- Correspondence: ; Tel.: +44-121-204-5011
| |
Collapse
|
9
|
Zamboni R, Zaltron A, Chauvet M, Sada C. Real-time precise microfluidic droplets label-sequencing combined in a velocity detection sensor. Sci Rep 2021; 11:17987. [PMID: 34504237 PMCID: PMC8429775 DOI: 10.1038/s41598-021-97392-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 08/24/2021] [Indexed: 11/09/2022] Open
Abstract
Droplets microfluidics is broadening the range of Lab on a Chip solutions that, however, still suffer from the lack of an adequate level of integration of optical detection and sensors. In fact, droplets are currently monitored by imaging techniques, mostly limited by a time-consuming data post-processing and big data storage. This work aims to overcome this weakness, presenting a fully integrated opto-microfluidic platform able to detect, label and characterize droplets without the need for imaging techniques. It consists of optical waveguides arranged in a Mach Zehnder's configuration and a microfluidic circuit both coupled in the same substrate. As a proof of concept, the work demonstrates the performances of this opto-microfluidic platform in performing a complete and simultaneous sequence labelling and identification of each single droplet, in terms of its optical properties, as well as velocity and lengths. Since the sensor is realized in lithium niobate crystals, which is also highly resistant to chemical attack and biocompatible, the future addition of multifunctional stages into the same substrate can be easily envisioned, extending the range of applicability of the final device.
Collapse
Affiliation(s)
- R Zamboni
- Physics and Astronomy Department, University of Padova, Via Marzolo 8, 35131, Padova, Italy.,Institute of Applied Physics, University of Münster, Corrensstrasse 2/4, 48149, Münster, Germany
| | - A Zaltron
- Physics and Astronomy Department, University of Padova, Via Marzolo 8, 35131, Padova, Italy
| | - M Chauvet
- FEMTO-ST Institute, UMR 6174, University of Bourgogne Franche-Comté, 15B Avenue des Montboucons, 25000, Besançon, France
| | - C Sada
- Physics and Astronomy Department, University of Padova, Via Marzolo 8, 35131, Padova, Italy.
| |
Collapse
|
10
|
Chang Y, Wang L, Li R, Zhang Z, Wang Q, Yang J, Guo CF, Pan T. First Decade of Interfacial Iontronic Sensing: From Droplet Sensors to Artificial Skins. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2003464. [PMID: 33346388 DOI: 10.1002/adma.202003464] [Citation(s) in RCA: 77] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/16/2020] [Indexed: 05/21/2023]
Abstract
Over the past decade, a brand-new pressure- and tactile-sensing modality, known as iontronic sensing has emerged, utilizing the supercapacitive nature of the electrical double layer (EDL) that occurs at the electrolytic-electronic interface, leading to ultrahigh device sensitivity, high noise immunity, high resolution, high spatial definition, optical transparency, and responses to both static and dynamic stimuli, in addition to thin and flexible device architectures. Together, it offers unique combination of enabling features to tackle the grand challenges in pressure- and tactile-sensing applications, in particular, with recent interest and rapid progress in the development of robotic intelligence, electronic skin, wearable health as well as the internet-of-things, from both academic and industrial communities. A historical perspective of the iontronic sensing discovery, an overview of the fundamental working mechanism along with its device architectures, a survey of the unique material aspects and structural designs dedicated, and finally, a discussion of the newly enabled applications, technical challenges, and future outlooks are provided for this promising sensing modality with implementations. The state-of-the-art developments of the iontronic sensing technology in its first decade are summarized, potentially providing a technical roadmap for the next wave of innovations and breakthroughs in this field.
Collapse
Affiliation(s)
- Yu Chang
- Bionic Sensing and Intelligence Center (BSIC), Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen, 518055, China
| | - Liu Wang
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Ruya Li
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100191, China
| | - Zhichao Zhang
- Micro and Nano-Innovations (MiNI) Laboratory, Department of Biomedical Engineering, University of California, Davis, CA, 95616, USA
| | - Qi Wang
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Junlong Yang
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Chuan Fei Guo
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Tingrui Pan
- Micro and Nano-Innovations (MiNI) Laboratory, Department of Biomedical Engineering, University of California, Davis, CA, 95616, USA
| |
Collapse
|
11
|
McIntyre D, Lashkaripour A, Densmore D. Rapid and inexpensive microfluidic electrode integration with conductive ink. LAB ON A CHIP 2020; 20:3690-3695. [PMID: 32895672 DOI: 10.1039/d0lc00763c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Electrode integration significantly increases the versatility of droplet microfluidics, enabling label-free sensing and manipulation at a single-droplet (single-cell) resolution. However, common fabrication techniques for integrating electronics into microfluidics are expensive, time-consuming, and can require cleanroom facilities. Here, we present a simple and cost-effective method for integrating electrodes into thermoplastic microfluidic chips using an off-the-shelf conductive ink. The developed conductive ink electrodes cost less than $10 for an entire chip, have been shown here in channel geometries as small as 75 μm by 50 μm, and can go from fabrication to testing within a day without a cleanroom. The geometric fabrication limits of this technique were explored over time, and proof-of-concept microfluidic devices for capacitance sensing, droplet merging, and droplet sorting were developed. This novel method complements existing rapid prototyping systems for microfluidics such as micromilling, laser cutting, and 3D printing, enabling their wider use and application.
Collapse
Affiliation(s)
- David McIntyre
- Boston University Biomedical Engineering Department, 44 Cummington Mall, Boston, USA and Biological Design Center, 610 Commonwealth Ave, Boston, USA
| | - Ali Lashkaripour
- Boston University Biomedical Engineering Department, 44 Cummington Mall, Boston, USA and Biological Design Center, 610 Commonwealth Ave, Boston, USA
| | - Douglas Densmore
- Biological Design Center, 610 Commonwealth Ave, Boston, USA and Boston University Electrical and Computer Engineering Department, 8 Saint Mary's St., Boston, USA.
| |
Collapse
|
12
|
Bonart H, Kahle C, Repke JU. Optimal Control of Droplets on a Solid Surface Using Distributed Contact Angles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:8894-8903. [PMID: 32628852 DOI: 10.1021/acs.langmuir.0c01242] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Controlling the shape and position of moving and pinned droplets on a solid surface is an important feature often found in microfluidic applications. However, automating them, e.g., for high-throughput applications, rarely involves model-based optimal control strategies. In this work, we demonstrate the optimal control of both the shape and position of a droplet sliding on an inclined surface. This basic test case is a fundamental building block in plenty of microfluidic designs. The static contact angle between the solid surface, the surrounding gas, and the liquid droplet serves as the control variable. By using several control patches, e.g., like that performed in electrowetting, the contact angles are allowed to vary in space and time. In computer experiments, we are able to calculate mathematically optimal contact angle distributions using gradient-based optimization. The dynamics of the droplet are described by the Cahn-Hilliard-Navier-Stokes equations. We anticipate our demonstration to be the starting point for more sophisticated optimal design and control concepts.
Collapse
Affiliation(s)
- Henning Bonart
- Technische Universität Berlin, Process Dynamics and Operations Group, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Christian Kahle
- Universität Koblenz-Landau, Universitätsstraße 1, 56070 Koblenz, Germany
| | - Jens-Uwe Repke
- Technische Universität Berlin, Process Dynamics and Operations Group, Straße des 17. Juni 135, 10623 Berlin, Germany
| |
Collapse
|
13
|
Bacon K, Lavoie A, Rao BM, Daniele M, Menegatti S. Past, Present, and Future of Affinity-based Cell Separation Technologies. Acta Biomater 2020; 112:29-51. [PMID: 32442784 PMCID: PMC10364325 DOI: 10.1016/j.actbio.2020.05.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/29/2020] [Accepted: 05/05/2020] [Indexed: 02/06/2023]
Abstract
Progress in cell purification technology is critical to increase the availability of viable cells for therapeutic, diagnostic, and research applications. A variety of techniques are now available for cell separation, ranging from non-affinity methods such as density gradient centrifugation, dielectrophoresis, and filtration, to affinity methods such as chromatography, two-phase partitioning, and magnetic-/fluorescence-assisted cell sorting. For clinical and analytical procedures that require highly purified cells, the choice of cell purification method is crucial, since every method offers a different balance between yield, purity, and bioactivity of the cell product. For most applications, the requisite purity is only achievable through affinity methods, owing to the high target specificity that they grant. In this review, we discuss past and current methods for developing cell-targeting affinity ligands and their application in cell purification, along with the benefits and challenges associated with different purification formats. We further present new technologies, like stimuli-responsive ligands and parallelized microfluidic devices, towards improving the viability and throughput of cell products for tissue engineering and regenerative medicine. Our comparative analysis provides guidance in the multifarious landscape of cell separation techniques and highlights new technologies that are poised to play a key role in the future of cell purification in clinical settings and the biotech industry. STATEMENT OF SIGNIFICANCE: Technologies for cell purification have served science, medicine, and industrial biotechnology and biomanufacturing for decades. This review presents a comprehensive survey of this field by highlighting the scope and relevance of all known methods for cell isolation, old and new alike. The first section covers the main classes of target cells and compares traditional non-affinity and affinity-based purification techniques, focusing on established ligands and chromatographic formats. The second section presents an excursus of affinity-based pseudo-chromatographic and non-chromatographic technologies, especially focusing on magnetic-activated cell sorting (MACS) and fluorescence-activated cell sorting (FACS). Finally, the third section presents an overview of new technologies and emerging trends, highlighting how the progress in chemical, material, and microfluidic sciences has opened new exciting avenues towards high-throughput and high-purity cell isolation processes. This review is designed to guide scientists and engineers in their choice of suitable cell purification techniques for research or bioprocessing needs.
Collapse
Affiliation(s)
- Kaitlyn Bacon
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Ashton Lavoie
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Balaji M Rao
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA; Biomanufacturing Training and Education Center (BTEC), North Carolina State University, Raleigh, NC 27695-7928, USA
| | - Michael Daniele
- Joint Department of Biomedical Engineering, North Carolina State University - University of North Carolina Chapel Hill, North Carolina, United States
| | - Stefano Menegatti
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA; Biomanufacturing Training and Education Center (BTEC), North Carolina State University, Raleigh, NC 27695-7928, USA.
| |
Collapse
|
14
|
Arjun A, Ajith RR, Kumar Ranjith S. Mixing characterization of binary-coalesced droplets in microchannels using deep neural network. BIOMICROFLUIDICS 2020; 14:034111. [PMID: 32549924 PMCID: PMC7274813 DOI: 10.1063/5.0008461] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 05/21/2020] [Indexed: 05/16/2023]
Abstract
Real-time object identification and classification are essential in many microfluidic applications especially in the droplet microfluidics. This paper discusses the application of convolutional neural networks to detect the merged microdroplet in the flow field and classify them in an on-the-go manner based on the extent of mixing. The droplets are generated in PMMA microfluidic devices employing flow-focusing and cross-flow configurations. The visualization of binary coalescence of droplets is performed by a CCD camera attached to a microscope, and the sequence of images is recorded. Different real-time object localization and classification networks such as You Only Look Once and Singleshot Multibox Detector are deployed for droplet detection and characterization. A custom dataset to train these deep neural networks to detect and classify is created from the captured images and labeled manually. The merged droplets are segregated based on the degree of mixing into three categories: low mixing, intermediate mixing, and high mixing. The trained model is tested against images taken at different ambient conditions, droplet shapes, droplet sizes, and binary-fluid combinations, which indeed exhibited high accuracy and precision in predictions. In addition, it is demonstrated that these schemes are efficient in localization of coalesced binary droplets from the recorded video or image and classify them based on grade of mixing irrespective of experimental conditions in real time.
Collapse
Affiliation(s)
- A Arjun
- Micro/nanofluidics Research Laboratory, Department of Mechanical Engineering, College of Engineering Trivandrum, Thiruvananathapuram 695016, Kerala, India
| | - R R Ajith
- Micro/nanofluidics Research Laboratory, Department of Mechanical Engineering, College of Engineering Trivandrum, Thiruvananathapuram 695016, Kerala, India
| | - S Kumar Ranjith
- Micro/nanofluidics Research Laboratory, Department of Mechanical Engineering, College of Engineering Trivandrum, Thiruvananathapuram 695016, Kerala, India
| |
Collapse
|
15
|
Zhang R, Ye Z, Gao M, Gao C, Zhang X, Li L, Gui L. Liquid metal electrode-enabled flexible microdroplet sensor. LAB ON A CHIP 2020; 20:496-504. [PMID: 31840725 DOI: 10.1039/c9lc00995g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This study presented a flexible liquid metal-based microdroplet capacitive sensor that would simply and accurately measure the speed and length of droplets flowing in microchannels. A pair of coplanar U-shaped electrodes was used to form a capacitance through droplet microchannels. Liquid metal was injected into polydimethylsiloxane (PDMS) channels to form the U-shaped electrodes. The sensor would generate a multi-plateau capacitance waveform as a droplet passes through the sensing area, and each plateau period corresponds to the droplet position in the sensing area. The droplet speed and length would be directly calculated from the multi-plateau capacitance waveform. The errors for the capacitive result relative to the real value were <7.2% for length and <2.8% for speed. Moreover, the sensor still maintained excellent performance for droplet length and speed measurement even though the microfluidic chip was bent to 96°. We have demonstrated that the capacitive sensor would be used for sweat rate monitoring.
Collapse
Affiliation(s)
- Renchang Zhang
- Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, 29 Zhongguancun East Road, Haidu District, Beijing 10019, China. and University of Chinese Academy of Sciences, 19 Yuquan road, Shijingshan District, Beijing 100039, China
| | - Zi Ye
- Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, 29 Zhongguancun East Road, Haidu District, Beijing 10019, China. and University of Chinese Academy of Sciences, 19 Yuquan road, Shijingshan District, Beijing 100039, China
| | - Meng Gao
- Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, 29 Zhongguancun East Road, Haidu District, Beijing 10019, China.
| | - Chang Gao
- Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, 29 Zhongguancun East Road, Haidu District, Beijing 10019, China. and University of Chinese Academy of Sciences, 19 Yuquan road, Shijingshan District, Beijing 100039, China
| | - Xudong Zhang
- Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, 29 Zhongguancun East Road, Haidu District, Beijing 10019, China. and University of Chinese Academy of Sciences, 19 Yuquan road, Shijingshan District, Beijing 100039, China
| | - Lei Li
- Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, 29 Zhongguancun East Road, Haidu District, Beijing 10019, China.
| | - Lin Gui
- Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, 29 Zhongguancun East Road, Haidu District, Beijing 10019, China. and University of Chinese Academy of Sciences, 19 Yuquan road, Shijingshan District, Beijing 100039, China
| |
Collapse
|
16
|
Saateh A, Kalantarifard A, Celik OT, Asghari M, Serhatlioglu M, Elbuken C. Real-time impedimetric droplet measurement (iDM). LAB ON A CHIP 2019; 19:3815-3824. [PMID: 31638132 DOI: 10.1039/c9lc00641a] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Droplet-based microfluidic systems require a precise control of droplet physical properties; hence, measuring the morphological properties of droplets is critical to obtain high sensitivity analysis. The ability to perform such measurements in real-time is another demand which has not been addressed yet. In this study, we used coplanar electrodes configured in the differential measurement mode for impedimetric measurement of size and velocity. To obtain the size of the droplets, detailed 3D finite element simulations of the system were performed. The interaction of the non-uniform electric field and the droplet was investigated. Electrode geometry optimization steps were described and design guideline rules were laid out. User-friendly software was developed for real-time observation of droplet length and velocity together with in situ statistical analysis results. A comparison between impedimetric and optical measurement tools is given. Finally, to illustrate the benefit of having real-time analysis, iDM was used to synthesize particles with a predefined monodispersity limit and to study the response times of syringe pump and pressure pump driven droplet generation devices. This analysis allows one to evaluate the 'warm-up' time for a droplet generator system, after which droplets reach the desired steady-state size required by the application of interest.
Collapse
Affiliation(s)
- Abtin Saateh
- Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center (UNAM), Bilkent University, Ankara 06800, Turkey.
| | - Ali Kalantarifard
- Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center (UNAM), Bilkent University, Ankara 06800, Turkey.
| | - Oguz Tolga Celik
- Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center (UNAM), Bilkent University, Ankara 06800, Turkey.
| | - Mohammad Asghari
- Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center (UNAM), Bilkent University, Ankara 06800, Turkey.
| | - Murat Serhatlioglu
- Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center (UNAM), Bilkent University, Ankara 06800, Turkey.
| | - Caglar Elbuken
- Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center (UNAM), Bilkent University, Ankara 06800, Turkey.
| |
Collapse
|
17
|
Ardeleanu MN, Popescu IN, Udroiu IN, Diaconu EM, Mihai S, Lungu E, Alhalaili B, Vidu R. Novel PDMS-Based Sensor System for MPWM Measurements of Picoliter Volumes in Microfluidic Devices. SENSORS (BASEL, SWITZERLAND) 2019; 19:E4886. [PMID: 31717452 PMCID: PMC6891790 DOI: 10.3390/s19224886] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/02/2019] [Accepted: 11/04/2019] [Indexed: 01/09/2023]
Abstract
In order for automatic microinjection to serve biomedical and genetic research, we have designed and manufactured a PDMS-based sensor with a circular section channel using the microwire molding technique. For the very precise control of microfluidic transport, we developed a microfluidic pulse width modulation system (MPWM) for automatic microinjections at a picoliter level. By adding a computer-aided detection and tracking of fluid-specific elements in the microfluidic circuit, the PDMS microchannel sensor became the basic element in the automatic control of the microinjection sensor. With the PDMS microinjection sensor, we precise measured microfluidic volumes under visual detection, assisted by very precise computer equipment (with precision below 1 μm) based on image processing. The calibration of the MPWM system was performed to increase the reproducibility of the results and to detect and measure microfluidic volumes. The novel PDMS-based sensor system for MPWM measurements of microfluidic volumes contributes to the advancement of intelligent control methods and techniques, which could lead to new developments in the design, control, and in applications of real-time intelligent sensor system control.
Collapse
Affiliation(s)
- Mihăiţă Nicolae Ardeleanu
- Faculty of Materials Engineering and Mechanics, Valahia University of Targoviste, 13 Aleea Sinaia Street, Targoviste 130004 Romania;
- S.C. Celteh Mezotronic S.R.L., Calea Câmpulung Street, No. 6A, Targoviste, 130092, Romania
| | - Ileana Nicoleta Popescu
- Faculty of Materials Engineering and Mechanics, Valahia University of Targoviste, 13 Aleea Sinaia Street, Targoviste 130004 Romania;
| | - Iulian Nicolae Udroiu
- Faculty of Electrical Engineering, Electronics and Information Technology, Valahia University of Targoviste, Targoviste 130004, Romania; (I.N.U.); (E.M.D.)
| | - Emil Mihai Diaconu
- Faculty of Electrical Engineering, Electronics and Information Technology, Valahia University of Targoviste, Targoviste 130004, Romania; (I.N.U.); (E.M.D.)
| | - Simona Mihai
- The Scientific and Technological Multidisciplinary Research Institute (ICSTM-UVT), Valahia University of Targoviste, Targoviste 130004, Romania;
| | - Emil Lungu
- Faculty of Sciences and Arts, Department of Mathematics, Valahia University of Targoviste, Targoviste 130004, Romania;
| | - Badriyah Alhalaili
- Nanotechnology and Advanced Materials Program, Kuwait Institute for Scientific Research, P.O. Box 24885, Safat 13109, Kuwait
| | - Ruxandra Vidu
- Department of Electrical and Computer Engineering, University of California Davis, Davis, CA 95616 USA
- Faculty of Materials Science and Engineering, University Politehnica of Bucharest, Bucharest 060042, Romania
| |
Collapse
|
18
|
Lombardo T, Lancellotti L, Souprayen C, Sella C, Thouin L. Electrochemical Detection of Droplets in Microfluidic Devices: Simultaneous Determination of Velocity, Size and Content. ELECTROANAL 2019. [DOI: 10.1002/elan.201900293] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Teo Lombardo
- Département de chimie, Ecole normale supérieureUniversité PSL, Sorbonne Université, CNRS 75005 Paris France
| | - Lidia Lancellotti
- Département de chimie, Ecole normale supérieureUniversité PSL, Sorbonne Université, CNRS 75005 Paris France
| | - Christelle Souprayen
- Département de chimie, Ecole normale supérieureUniversité PSL, Sorbonne Université, CNRS 75005 Paris France
| | - Catherine Sella
- Département de chimie, Ecole normale supérieureUniversité PSL, Sorbonne Université, CNRS 75005 Paris France
| | - Laurent Thouin
- Département de chimie, Ecole normale supérieureUniversité PSL, Sorbonne Université, CNRS 75005 Paris France
| |
Collapse
|
19
|
Zhang J, Hassan MR, Rallabandi B, Wang C. Migration of ferrofluid droplets in shear flow under a uniform magnetic field. SOFT MATTER 2019; 15:2439-2446. [PMID: 30801084 DOI: 10.1039/c8sm02522c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Manipulation of droplets based on physical properties (e.g., size, interfacial tension, electrical, and mechanical properties) is a critical step in droplet microfluidics. Manipulations based on magnetic fields have several benefits compared to other active methods. While traditional magnetic manipulations require spatially inhomogeneous fields to apply forces, the fast spatial decay of the magnetic field strength from the source makes these techniques difficult to scale up. In this work, we report the observation of lateral migration of ferrofluid (or magnetic) droplets under the combined action of a uniform magnetic field and a pressure-driven flow in a microchannel. While the uniform magnetic field exerts negligible net force on the droplet, the Maxwell stresses deform the droplet to achieve elongated shapes and modulate the orientation relative to the fluid flow. Hydrodynamic interactions between the droplets and the channel walls result in a directional lateral migration. We experimentally study the effects of field strength and direction, and interfacial tension, and use analytical and numerical modeling to understand the lateral migration mechanism.
Collapse
Affiliation(s)
- Jie Zhang
- Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, 400 W. 13th St., Rolla, Missouri 65409, USA.
| | | | | | | |
Collapse
|
20
|
Kaushik AM, Hsieh K, Wang TH. Droplet microfluidics for high-sensitivity and high-throughput detection and screening of disease biomarkers. WILEY INTERDISCIPLINARY REVIEWS. NANOMEDICINE AND NANOBIOTECHNOLOGY 2018; 10:e1522. [PMID: 29797414 PMCID: PMC6185786 DOI: 10.1002/wnan.1522] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 03/02/2018] [Accepted: 03/10/2018] [Indexed: 12/17/2022]
Abstract
Biomarkers are nucleic acids, proteins, single cells, or small molecules in human tissues or biological fluids whose reliable detection can be used to confirm or predict disease and disease states. Sensitive detection of biomarkers is therefore critical in a variety of applications including disease diagnostics, therapeutics, and drug screening. Unfortunately for many diseases, low abundance of biomarkers in human samples and low sample volumes render standard benchtop platforms like 96-well plates ineffective for reliable detection and screening. Discretization of bulk samples into a large number of small volumes (fL-nL) via droplet microfluidic technology offers a promising solution for high-sensitivity and high-throughput detection and screening of biomarkers. Several microfluidic strategies exist for high-throughput biomarker digitization into droplets, and these strategies have been utilized by numerous droplet platforms for nucleic acid, protein, and single-cell detection and screening. While the potential of droplet-based platforms has led to burgeoning interest in droplets, seamless integration of sample preparation technologies and automation of platforms from biological sample to answer remain critical components that can render these platforms useful in the clinical setting in the near future. This article is categorized under: Diagnostic Tools > Biosensing Diagnostic Tools > Diagnostic Nanodevices Therapeutic Approaches and Drug Discovery > Emerging Technologies Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease.
Collapse
Affiliation(s)
| | - Kuangwen Hsieh
- Department of Mechanical Engineering, Johns Hopkins University
| | - Tza-Huei Wang
- Department of Mechanical Engineering, Department of Biomedical Engineering, Johns Hopkins University
| |
Collapse
|
21
|
Rickel JMR, Dixon AJ, Klibanov AL, Hossack JA. A flow focusing microfluidic device with an integrated Coulter particle counter for production, counting and size characterization of monodisperse microbubbles. LAB ON A CHIP 2018; 18:2653-2664. [PMID: 30070301 PMCID: PMC6566100 DOI: 10.1039/c8lc00496j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Flow focusing microfluidic devices (FFMDs) have been investigated for the production of monodisperse populations of microbubbles for chemical, biomedical and mechanical engineering applications. High-speed optical microscopy is commonly used to monitor FFMD microbubble production parameters, such as diameter and production rate, but this limits the scalability and portability of the approach. In this work, a novel FFMD design featuring integrated electronics for measuring microbubble diameters and production rates is presented. A micro Coulter particle counter (μCPC), using electrodes integrated within the expanding nozzle of an FFMD (FFMD-μCPC), was designed, fabricated and tested. Finite element analysis (FEA) of optimal electrode geometry was performed and validated with experimental data. Electrical data was collected for 8-20 μm diameter microbubbles at production rates up to 3.25 × 105 MB s-1 and compared to both high-speed microscopy data and FEA simulations. Within a valid operating regime, Coulter counts of microbubble production rates matched optical reference values. The Coulter method agreed with the optical reference method in evaluating the microbubble diameter to a coefficient of determination of R2 = 0.91.
Collapse
Affiliation(s)
- J M Robert Rickel
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA.
| | | | | | | |
Collapse
|
22
|
Dhar P. Thermofluidic Transport in Droplets under Electromagnetic Stimulus: A Comprehensive Review. J Indian Inst Sci 2018. [DOI: 10.1007/s41745-018-0088-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
23
|
A Cosine Similarity Algorithm Method for Fast and Accurate Monitoring of Dynamic Droplet Generation Processes. Sci Rep 2018; 8:9967. [PMID: 29967430 PMCID: PMC6028520 DOI: 10.1038/s41598-018-28270-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 06/20/2018] [Indexed: 11/28/2022] Open
Abstract
Droplet microfluidics has attracted significant interests in functional microcapsule synthesis, pharmaceuticals, fine chemicals, cosmetics and biomedical research. The low variability of performing chemical reactions inside droplets could benefit from improved homogeneity and reproducibility. Therefore, accurate and convenient methods are needed to monitor dynamic droplet generation processes. Here, a novel Cosine Similarity Algorithm (CSA) method was developed to monitor the droplet generation frequency accurately and rapidly. With a microscopic droplet generation video clip captured with a high-speed camera, droplet generation frequency can be computed accurately by calculating the cosine similarities between the frames in the video clip. Four kinds of dynamic droplet generation processes were investigated including (1) a stable condition in a single microfluidic channel, (2) a stable condition in multiple microfluidic channels, (3) a single microfluidic channel with artificial disturbances, and (4) microgel fabrication with or without artificial disturbances. For a video clip with 5,000 frames and a spatial resolution of 512 × 62 pixels, droplet generation frequency up to 4,707.9 Hz can be calculated in less than 1.70 s with an absolute relative calculation error less than 0.08%. Artificial disturbances in droplet generation processes can be precisely determined using the CSA method. This highly effective CSA method could be a powerful tool for further promoting the research of droplet microfluidics.
Collapse
|
24
|
Fernandes AC, Gernaey KV, Krühne U. “Connecting worlds – a view on microfluidics for a wider application”. Biotechnol Adv 2018; 36:1341-1366. [DOI: 10.1016/j.biotechadv.2018.05.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 04/30/2018] [Accepted: 05/01/2018] [Indexed: 01/19/2023]
|
25
|
Wang Z, Tan L, Pan X, Liu G, He Y, Jin W, Li M, Hu Y, Gu H. Self-Powered Viscosity and Pressure Sensing in Microfluidic Systems Based on the Piezoelectric Energy Harvesting of Flowing Droplets. ACS APPLIED MATERIALS & INTERFACES 2017; 9:28586-28595. [PMID: 28783301 DOI: 10.1021/acsami.7b08541] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The rapid development of microscaled piezoelectric energy harvesters has provided a simple and highly efficient way for building self-powered sensor systems through harvesting the mechanical energy from the ambient environment. In this work, a self-powered microfluidic sensor that can harvest the mechanical energy of the fluid and simultaneously monitor their characteristics was fabricated by integrating the flexible piezoelectric poly(vinylidene fluoride) (PVDF) nanofibers with the well-designed microfluidic chips. Those devices could generate open-circuit high output voltage up to 1.8 V when a droplet of water is flowing past the suspended PVDF nanofibers and result in their periodical deformations. The impulsive output voltage signal allowed them to be utilized for droplets or bubbles counting in the microfluidic systems. Furthermore, the devices also exhibited self-powered sensing behavior due to the decreased voltage amplitude with increasing input pressure and liquid viscosity. The drop of output voltage could be attributed to the variation of flow condition and velocity of the droplets, leading to the reduced deformation of the piezoelectric PVDF layer and the decrease of the generated piezoelectric potential.
Collapse
Affiliation(s)
- Zhao Wang
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials - Hubei Key Laboratory of Ferro & Piezoelectric Materials and Devices, Faculty of Physics & Electronic Sciences, Hubei University , Wuhan 430062, People's Republic of China
| | - Lun Tan
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials - Hubei Key Laboratory of Ferro & Piezoelectric Materials and Devices, Faculty of Physics & Electronic Sciences, Hubei University , Wuhan 430062, People's Republic of China
| | - Xumin Pan
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials - Hubei Key Laboratory of Ferro & Piezoelectric Materials and Devices, Faculty of Physics & Electronic Sciences, Hubei University , Wuhan 430062, People's Republic of China
| | - Gao Liu
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials - Hubei Key Laboratory of Ferro & Piezoelectric Materials and Devices, Faculty of Physics & Electronic Sciences, Hubei University , Wuhan 430062, People's Republic of China
| | - Yahua He
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials - Hubei Key Laboratory of Ferro & Piezoelectric Materials and Devices, Faculty of Physics & Electronic Sciences, Hubei University , Wuhan 430062, People's Republic of China
| | - Wenchao Jin
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials - Hubei Key Laboratory of Ferro & Piezoelectric Materials and Devices, Faculty of Physics & Electronic Sciences, Hubei University , Wuhan 430062, People's Republic of China
| | - Meng Li
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials - Hubei Key Laboratory of Ferro & Piezoelectric Materials and Devices, Faculty of Physics & Electronic Sciences, Hubei University , Wuhan 430062, People's Republic of China
| | - Yongming Hu
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials - Hubei Key Laboratory of Ferro & Piezoelectric Materials and Devices, Faculty of Physics & Electronic Sciences, Hubei University , Wuhan 430062, People's Republic of China
| | - Haoshuang Gu
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials - Hubei Key Laboratory of Ferro & Piezoelectric Materials and Devices, Faculty of Physics & Electronic Sciences, Hubei University , Wuhan 430062, People's Republic of China
| |
Collapse
|
26
|
Sesen M, Alan T, Neild A. Droplet control technologies for microfluidic high throughput screening (μHTS). LAB ON A CHIP 2017. [PMID: 28631799 DOI: 10.1039/c7lc00005g] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The transition from micro well plate and robotics based high throughput screening (HTS) to chip based screening has already started. This transition promises reduced droplet volumes thereby decreasing the amount of fluids used in these studies. Moreover, it significantly boosts throughput allowing screening to keep pace with the overwhelming number of molecular targets being discovered. In this review, we analyse state-of-the-art droplet control technologies that exhibit potential to be used in this new generation of screening devices. Since these systems are enclosed and usually planar, even some of the straightforward methods used in traditional HTS such as pipetting and reading can prove challenging to replicate in microfluidic high throughput screening (μHTS). We critically review the technologies developed for this purpose in depth, describing the underlying physics and discussing the future outlooks.
Collapse
Affiliation(s)
- Muhsincan Sesen
- Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia.
| | | | | |
Collapse
|
27
|
Xi HD, Zheng H, Guo W, Gañán-Calvo AM, Ai Y, Tsao CW, Zhou J, Li W, Huang Y, Nguyen NT, Tan SH. Active droplet sorting in microfluidics: a review. LAB ON A CHIP 2017; 17:751-771. [PMID: 28197601 DOI: 10.1039/c6lc01435f] [Citation(s) in RCA: 174] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The ability to manipulate and sort droplets is a fundamental issue in droplet-based microfluidics. Various lab-on-a-chip applications can only be realized if droplets are systematically categorized and sorted. These micron-sized droplets act as ideal reactors which compartmentalize different biological and chemical reagents. Array processing of these droplets hinges on the competence of the sorting and integration into the fluidic system. Recent technological advances only allow droplets to be actively sorted at the rate of kilohertz or less. In this review, we present state-of-the-art technologies which are implemented to efficiently sort droplets. We classify the concepts according to the type of energy implemented into the system. We also discuss various key issues and provide insights into various systems.
Collapse
Affiliation(s)
- Heng-Dong Xi
- School of Aeronautics, Northwestern Polytechnical University, 127 West Youyi Rd., Xi'an, Shaanxi, China
| | - Hao Zheng
- School of Aeronautics, Northwestern Polytechnical University, 127 West Youyi Rd., Xi'an, Shaanxi, China
| | - Wei Guo
- School of Aeronautics, Northwestern Polytechnical University, 127 West Youyi Rd., Xi'an, Shaanxi, China and Queensland Micro- and Nanotechnology Centre, Griffith University, 170 Kessels Road, Brisbane, QLD 4111, Australia.
| | - Alfonso M Gañán-Calvo
- Depto. de Ingeniería Aeroespacial y Mecánica de Fluidos, Universidad de Sevilla, E-41092 Sevilla, Spain
| | - Ye Ai
- Pillar of Engineering Product Development, Singapore University of Technology and Design, Singapore
| | - Chia-Wen Tsao
- Department of Mechanical Engineering, National Central University, No. 300, Zhongda Rd, Taoyuan, Taiwan
| | - Jun Zhou
- School of Information and Communication Technology, Griffith University, Nathan, QLD 4111, Australia
| | - Weihua Li
- School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Yanyi Huang
- Biodynamic Optical Imaging Center, Peking University, Beijing 100871, China
| | - Nam-Trung Nguyen
- Queensland Micro- and Nanotechnology Centre, Griffith University, 170 Kessels Road, Brisbane, QLD 4111, Australia.
| | - Say Hwa Tan
- Queensland Micro- and Nanotechnology Centre, Griffith University, 170 Kessels Road, Brisbane, QLD 4111, Australia.
| |
Collapse
|
28
|
Hassan SU, Nightingale AM, Niu X. Optical Flow Cell for Measuring Size, Velocity and Composition of Flowing Droplets. MICROMACHINES 2017. [PMCID: PMC6190161 DOI: 10.3390/mi8020058] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Sammer-ul Hassan
- Faculty of Engineering and the Environment, University of Southampton, Southampton SO17 1BJ, UK; (S.H.); (A.M.N.)
- Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Adrian M. Nightingale
- Faculty of Engineering and the Environment, University of Southampton, Southampton SO17 1BJ, UK; (S.H.); (A.M.N.)
- Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Xize Niu
- Faculty of Engineering and the Environment, University of Southampton, Southampton SO17 1BJ, UK; (S.H.); (A.M.N.)
- Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
- Correspondence: ; Tel.: +44-23-8059-2367
| |
Collapse
|
29
|
Sesen M, Devendran C, Malikides S, Alan T, Neild A. Surface acoustic wave enabled pipette on a chip. LAB ON A CHIP 2017; 17:438-447. [PMID: 27995242 DOI: 10.1039/c6lc01318j] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Mono-disperse droplet formation in microfluidic devices allows the rapid production of thousands of identical droplets and has enabled a wide range of chemical and biological studies through repeat tests performed at pico-to-nanoliter volume samples. However, it is exactly this efficiency of production which has hindered the ability to carefully control the location and quantity of the distribution of various samples on a chip - the key requirement for replicating micro well plate based high throughput screening in vastly reduced volumetric scales. To address this need, here, we present a programmable microfluidic chip capable of pipetting samples from mobile droplets with high accuracy using a non-contact approach. Pipette on a chip (PoaCH) system selectively ejects (pipettes) part of a droplet into a customizable reaction chamber using surface acoustic waves (SAWs). Droplet pipetting is shown to range from as low as 150 pL up to 850 pL with precision down to tens of picoliters. PoaCH offers ease of integration with existing lab on a chip systems as well as a robust and contamination-free droplet manipulation technique in closed microchannels enabling potential implementation in screening and other studies.
Collapse
Affiliation(s)
- Muhsincan Sesen
- Laboratory for Microsystems, Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia.
| | - Citsabehsan Devendran
- Laboratory for Microsystems, Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia.
| | - Sean Malikides
- Laboratory for Microsystems, Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia.
| | - Tuncay Alan
- Laboratory for Microsystems, Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia.
| | - Adrian Neild
- Laboratory for Microsystems, Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia.
| |
Collapse
|
30
|
An on-chip imaging droplet-sorting system: a real-time shape recognition method to screen target cells in droplets with single cell resolution. Sci Rep 2017; 7:40072. [PMID: 28059147 PMCID: PMC5216404 DOI: 10.1038/srep40072] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 11/30/2016] [Indexed: 12/29/2022] Open
Abstract
A microfluidic on-chip imaging cell sorter has several advantages over conventional cell sorting methods, especially to identify cells with complex morphologies such as clusters. One of the remaining problems is how to efficiently discriminate targets at the species level without labelling. Hence, we developed a label-free microfluidic droplet-sorting system based on image recognition of cells in droplets. To test the applicability of this method, a mixture of two plankton species with different morphologies (Dunaliella tertiolecta and Phaeodactylum tricornutum) were successfully identified and discriminated at a rate of 10 Hz. We also examined the ability to detect the number of objects encapsulated in a droplet. Single cell droplets sorted into collection channels showed 91 ± 4.5% and 90 ± 3.8% accuracy for D. tertiolecta and P. tricornutum, respectively. Because we used image recognition to confirm single cell droplets, we achieved highly accurate single cell sorting. The results indicate that the integrated method of droplet imaging cell sorting can provide a complementary sorting approach capable of isolating single target cells from a mixture of cells with high accuracy without any staining.
Collapse
|
31
|
Label-Free Analysis and Sorting of Microalgae and Cyanobacteria in Microdroplets by Intrinsic Chlorophyll Fluorescence for the Identification of Fast Growing Strains. Anal Chem 2016; 88:10445-10451. [PMID: 27677315 DOI: 10.1021/acs.analchem.6b02364] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Microalgae and cyanobacteria are promising organisms for sustainable biofuel production, but several challenges remain to make this economically viable, including identification of optimized strains with high biomass productivity. Here we report on a novel methodology for the label-free screening and sorting of cyanobacteria and microalgae in a microdroplet platform. We show for the first time that chlorophyll fluorescence can be used to measure differences in biomass between populations of picoliter microdroplets containing different species of cyanobacteria, Synechocystis PCC 6803 and Synechococcus PCC 7002, which exhibit different growth dynamics in bulk culture. The potential and robustness of this label-free screening approach is further demonstrated by the screening and sorting of cells of the green alga Chlamydomonas reinhardtii encapsulated in droplets.
Collapse
|
32
|
Wong D, Ren CL. Microfluidic droplet trapping, splitting and merging with feedback controls and state space modelling. LAB ON A CHIP 2016; 16:3317-3329. [PMID: 27435753 DOI: 10.1039/c6lc00626d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We combine image processing and feedback controls to regulate droplet movements. A general modelling approach is provided to describe droplet motion in a pressure-driven microfluidic channel network. A state space model is derived from electric circuit analogy and validated with experimental data. We then design simple decentralized controllers to stabilize droplet movement. The controllers can trap droplets at requested locations by fine tuning inlet pressures constantly. Finally, we demonstrate the ability to split and merge the same droplet repeatedly in a simple T-junction. No embedded electrodes are required, and this technique can be implemented solely with a camera, a personal computer, and commercially available E/P transducers.
Collapse
Affiliation(s)
- David Wong
- Mechanical and Mechatronics Engineering, University of Waterloo, 200, University Avenue West, Waterloo, Canada.
| | - Carolyn L Ren
- Mechanical and Mechatronics Engineering, University of Waterloo, 200, University Avenue West, Waterloo, Canada.
| |
Collapse
|
33
|
Samiei E, Tabrizian M, Hoorfar M. A review of digital microfluidics as portable platforms for lab-on a-chip applications. LAB ON A CHIP 2016; 16:2376-96. [PMID: 27272540 DOI: 10.1039/c6lc00387g] [Citation(s) in RCA: 195] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Following the development of microfluidic systems, there has been a high tendency towards developing lab-on-a-chip devices for biochemical applications. A great deal of effort has been devoted to improve and advance these devices with the goal of performing complete sets of biochemical assays on the device and possibly developing portable platforms for point of care applications. Among the different microfluidic systems used for such a purpose, digital microfluidics (DMF) shows high flexibility and capability of performing multiplex and parallel biochemical operations, and hence, has been considered as a suitable candidate for lab-on-a-chip applications. In this review, we discuss the most recent advances in the DMF platforms, and evaluate the feasibility of developing multifunctional packages for performing complete sets of processes of biochemical assays, particularly for point-of-care applications. The progress in the development of DMF systems is reviewed from eight different aspects, including device fabrication, basic fluidic operations, automation, manipulation of biological samples, advanced operations, detection, biological applications, and finally, packaging and portability of the DMF devices. Success in developing the lab-on-a-chip DMF devices will be concluded based on the advances achieved in each of these aspects.
Collapse
Affiliation(s)
- Ehsan Samiei
- School of Engineering, University of British Columbia, 3333 University Way, Kelowna, BC V1V 1V7, Canada.
| | | | | |
Collapse
|
34
|
Li Y, Li H, Baker RJ. A Low-Cost and High-Resolution Droplet Position Detector for an Intelligent Electrowetting on Dielectric Device. ACTA ACUST UNITED AC 2015; 20:663-9. [DOI: 10.1177/2211068214566940] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Indexed: 11/16/2022]
|
35
|
Raj MD, Rengaswamy R. Investigating Arrangement of Composite Drops in Two-Dimensional Microchannels Using Multiagent Simulations: A Design Perspective. Ind Eng Chem Res 2015. [DOI: 10.1021/acs.iecr.5b02681] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- M. Danny Raj
- 150 Mechanical Sciences
Block, Indian Institute of Technology Madras, Chennai-600036, India
| | - R. Rengaswamy
- 150 Mechanical Sciences
Block, Indian Institute of Technology Madras, Chennai-600036, India
| |
Collapse
|
36
|
Ahn MM, Im DJ, Yoo BS, Kang IS. Characterization of electrode alignment for optimal droplet charging and actuation in droplet-based microfluidic system. Electrophoresis 2015; 36:2086-93. [DOI: 10.1002/elps.201500141] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 05/06/2015] [Accepted: 05/06/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Myung Mo Ahn
- Department of Chemical Engineering; Pohang University of Science and Technology; Pohang South Korea
| | - Do Jin Im
- Department of Chemical Engineering; Pukyong National University; Nam-Gu. Busan South Korea
| | - Byeong Sun Yoo
- Department of Chemical Engineering; Pohang University of Science and Technology; Pohang South Korea
| | - In Seok Kang
- Department of Chemical Engineering; Pohang University of Science and Technology; Pohang South Korea
| |
Collapse
|
37
|
Jia Y, Ren Y, Jiang H. Continuous dielectrophoretic particle separation using a microfluidic device with 3D electrodes and vaulted obstacles. Electrophoresis 2015; 36:1744-53. [DOI: 10.1002/elps.201400565] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 04/20/2015] [Accepted: 04/23/2015] [Indexed: 12/11/2022]
Affiliation(s)
- Yankai Jia
- School of Mechatronics Engineering; Harbin Institute of Technology; Harbin P. R. China
| | - Yukun Ren
- School of Mechatronics Engineering; Harbin Institute of Technology; Harbin P. R. China
| | - Hongyuan Jiang
- School of Mechatronics Engineering; Harbin Institute of Technology; Harbin P. R. China
| |
Collapse
|
38
|
Dong T, Barbosa C. Capacitance variation induced by microfluidic two-phase flow across insulated interdigital electrodes in lab-on-chip devices. SENSORS 2015; 15:2694-708. [PMID: 25629705 PMCID: PMC4367328 DOI: 10.3390/s150202694] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 01/20/2015] [Indexed: 11/16/2022]
Abstract
Microfluidic two-phase flow detection has attracted plenty of interest in various areas of biology, medicine and chemistry. This work presents a capacitive sensor using insulated interdigital electrodes (IDEs) to detect the presence of droplets in a microchannel. This droplet sensor is composed of a glass substrate, patterned gold electrodes and an insulation layer. A polydimethylsiloxane (PDMS) cover bonded to the multilayered structure forms a microchannel. Capacitance variation induced by the droplet passage was thoroughly investigated with both simulation and experimental work. Olive oil and deionized water were employed as the working fluids in the experiments to demonstrate the droplet sensor. The results show a good sensitivity of the droplet with the appropriate measurement connection. This capacitive droplet sensor is promising to be integrated into a lab-on-chip device for in situ monitoring/counting of droplets or bubbles.
Collapse
Affiliation(s)
- Tao Dong
- Institute of Applied Micro-Nano Science and Technology, Chongqing Technology and Business University, Chongqing 400067, China.
| | - Cátia Barbosa
- Department of Micro and Nano Systems Technology (IMST), Faculty of Technology and Maritime Sciences (TekMar), Buskerud and Vestfold University College (HBV), Borre 3184, Norway
| |
Collapse
|
39
|
Li J, Wang Y, Dong E, Chen H. USB-driven microfluidic chips on printed circuit boards. LAB ON A CHIP 2014; 14:860-864. [PMID: 24401912 DOI: 10.1039/c3lc51155c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A technology is presented to fabricate a microfluidic chip in which the microchannels and the microelectrodes of sensors are integrated directly into the copper sheet on a printed circuit board. Then, we demonstrate an application of the generation of oil-in-water and water-in-oil emulsion droplets on this microfluidic chip driven by a USB interface, and the droplet size is detected by the microelectrodes on the downstream microchannel. The integration of the microfluidic chip is improved by the direct connection of the channels to the microelectrodes of the driving unit and of the sensors on the same substrate, and it is a promising way to integrate microfluidics into a more complex micro electrical-mechanical system (MEMS).
Collapse
Affiliation(s)
- Jiang Li
- School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China.
| | | | | | | |
Collapse
|
40
|
Gray BL. New Opportunities for Polymer Nanocomposites in Microfluidics and Biomedical MEMS: An introduction to cutting-edge composite polymer materials for use in microfluidics and biomedical MEMS. IEEE NANOTECHNOLOGY MAGAZINE 2014. [DOI: 10.1109/mnano.2014.2309495] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
41
|
Hatch AC, Ray T, Lintecum K, Youngbull C. Continuous flow real-time PCR device using multi-channel fluorescence excitation and detection. LAB ON A CHIP 2014; 14:562-568. [PMID: 24297040 DOI: 10.1039/c3lc51236c] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
High throughput automation is greatly enhanced using techniques that employ conveyor belt strategies with un-interrupted streams of flow. We have developed a 'conveyor belt' analog for high throughput real-time quantitative Polymerase Chain Reaction (qPCR) using droplet emulsion technology. We developed a low power, portable device that employs LED and fiber optic fluorescence excitation in conjunction with a continuous flow thermal cycler to achieve multi-channel fluorescence detection for real-time fluorescence measurements. Continuously streaming fluid plugs or droplets pass through tubing wrapped around a two-temperature zone thermal block with each wrap of tubing fluorescently coupled to a 64-channel multi-anode PMT. This work demonstrates real-time qPCR of 0.1-10 μL droplets or fluid plugs over a range of 7 orders of magnitude concentration from 1 × 10(1) to 1 × 10(7). The real-time qPCR analysis allows dynamic range quantification as high as 1 × 10(7) copies per 10 μL reaction, with PCR efficiencies within the range of 90-110% based on serial dilution assays and a limit of detection of 10 copies per rxn. The combined functionality of continuous flow, low power thermal cycling, high throughput sample processing, and real-time qPCR improves the rates at which biological or environmental samples can be continuously sampled and analyzed.
Collapse
Affiliation(s)
- Andrew C Hatch
- Arizona State University School of Earth and Space Exploration, 781 E Terrace Road, ISTB4 Room 795, Tempe, AZ 85287, USA.
| | | | | | | |
Collapse
|
42
|
Gu Y, Fisher AC. An AC voltammetry approach for the detection of droplets in microfluidic devices. Analyst 2013; 138:4448-52. [PMID: 23799232 DOI: 10.1039/c3an00822c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A simple electrochemical method using ac voltammetry to detect aqueous droplets up to 480 droplets per second in a flow-focusing microfluidic device is presented. The method offers a promising and versatile platform with simple and inexpensive instrumentation for droplets real time detection and preliminary characterization.
Collapse
Affiliation(s)
- Yunfeng Gu
- Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museum Site, Pembroke Street, Cambridge, CB2 3RA, UK
| | | |
Collapse
|
43
|
Li S, Ding X, Guo F, Chen Y, Lapsley MI, Lin SCS, Wang L, McCoy JP, Cameron CE, Huang TJ. An on-chip, multichannel droplet sorter using standing surface acoustic waves. Anal Chem 2013; 85:5468-74. [PMID: 23647057 PMCID: PMC3988909 DOI: 10.1021/ac400548d] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The emerging field of droplet microfluidics requires effective on-chip handling and sorting of droplets. In this work, we demonstrate a microfluidic device that is capable of sorting picoliter water-in-oil droplets into multiple outputs using standing surface acoustic waves (SSAW). This device integrates a single-layer microfluidic channel with interdigital transducers (IDTs) to achieve on-chip droplet generation and sorting. Within the SSAW field, water-in-oil droplets experience an acoustic radiation force and are pushed toward the acoustic pressure node. As a result, by tuning the frequency of the SSAW excitation, the position of the pressure nodes can be changed and droplets can be sorted to different outlets at rates up to 222 droplets s(-1). With its advantages in simplicity, controllability, versatility, noninvasiveness, and capability to be integrated with other on-chip components such as droplet manipulation and optical detection units, the technique presented here could be valuable for the development of droplet-based micro total analysis systems (μTAS).
Collapse
Affiliation(s)
- Sixing Li
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA
- Cell and Developmental Biology (CDB) Graduate Program, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802
| | - Xiaoyun Ding
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA
| | - Feng Guo
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA
| | - Yuchao Chen
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA
| | - Michael Ian Lapsley
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA
| | - Sz-Chin Steven Lin
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA
| | - Lin Wang
- Ascent Bio-Nano Technologies Inc., State College, PA 16801
| | - J. Philip McCoy
- National Heart, Lung, and Blood Institute at NIH, Bethesda, MD 20892
| | - Craig E. Cameron
- Cell and Developmental Biology (CDB) Graduate Program, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802
| | - Tony Jun Huang
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA
- Cell and Developmental Biology (CDB) Graduate Program, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802
| |
Collapse
|
44
|
Hatch AC, Patel A, Beer NR, Lee AP. Passive droplet sorting using viscoelastic flow focusing. LAB ON A CHIP 2013; 13:1308-15. [PMID: 23380996 DOI: 10.1039/c2lc41160a] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We present a study of passive hydrodynamic droplet sorting in microfluidic channels based on intrinsic viscoelastic fluid properties. Sorting is achieved by tuning the droplets' intrinsic viscous and viscoelastic properties relative to the continuous oil phase to achieve a positive or negative lateral migration toward high or low shear gradients in the channel. In the presence of weakly viscoelastic fluid behavior, droplets with a viscosity ratio, κ, between 0.5-10 were found to migrate toward a high shear gradient near the channel walls. For all other κ-values, or Newtonian fluids, droplets would migrate toward a low shear gradient at the channel centerline. It was also found that for strongly viscoelastic fluids with low interfacial tension, droplets would migrate toward the edge even with κ-values lower than 0.5. The resulting bi-directional lateral droplet migration between different droplets allows size-independent sorting. Still, their sorting efficiencies are dependent on droplet size, intrinsic fluid elasticity, viscosity, droplet deformability, and overall fluid shear rates. Based on these findings, we demonstrate >200 Hz passive droplet sorting frequencies and achieve >100 fold enrichment factors without the need to actively sense and/or control active mechanisms. Using a low viscosity oil phase of 6.25 cPs, we demonstrate sorting discrimination of 1 cPs and 5 cPs aqueous droplets with κ-values of 0.2 and 0.8 respectively.
Collapse
Affiliation(s)
- Andrew C Hatch
- Biomedical Engineering, University of California-Irvine, CA 92697, USA.
| | | | | | | |
Collapse
|
45
|
Zhou H, Yao S. Electrostatic charging and control of droplets in microfluidic devices. LAB ON A CHIP 2013; 13:962-9. [PMID: 23338121 DOI: 10.1039/c2lc41060e] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Precharged droplets can facilitate manipulation and control of low-volume liquids in droplet-based microfluidics. In this paper, we demonstrate non-contact electrostatic charging of droplets by polarizing a neutral droplet and splitting it into two oppositely charged daughter droplets in a T-junction microchannel. We performed numerical simulation to analyze the non-contact charging process and proposed a new design with a notch at the T-junction in aid of droplet splitting for more efficient charging. We experimentally characterized the induced charge in droplets in microfabricated devices. The experimental results agreed well with the simulation. Finally, we demonstrated highly effective droplet manipulation in a path selection unit appending to the droplet charging. We expect our work could enable precision manipulation of droplets for more complex liquid handling in microfluidics and promote electric-force based manipulation in 'lab-on-a-chip' systems.
Collapse
Affiliation(s)
- Hongbo Zhou
- Department of Mechanical Engineering, The Hong Kong University of Science and Technology, Hong Kong, China
| | | |
Collapse
|
46
|
Mustin B, Stoeber B. Low cost integration of 3D-electrode structures into microfluidic devices by replica molding. LAB ON A CHIP 2012; 12:4702-8. [PMID: 23007263 DOI: 10.1039/c2lc40728k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
We demonstrate a new replica molding method for integrating 3D-composite electrodes into microfluidic devices made from polydimethylsiloxane (PDMS) at low cost. Our process does not require work in a cleanroom, expensive materials, or expensive equipment once a micro mold has been fabricated using standard multilayer SU-8 photolithography. Different device geometries have been fabricated to demonstrate the capabilities and limitations of the method. The electrical properties of the composite electrode material are characterized. Furthermore, a device for concentrating particles via AC-dielectrophoresis is presented as an example for a potential application of the fabrication process.
Collapse
Affiliation(s)
- Benjamin Mustin
- The University of British Columbia, 2054-6250 Applied Science Lane, Vancouver, BC V6T 1Z4, Canada.
| | | |
Collapse
|
47
|
Bhattacharjee B, Najjaran H. Droplet sensing by measuring the capacitance between coplanar electrodes in a digital microfluidic system. LAB ON A CHIP 2012; 12:4416-4423. [PMID: 22930258 DOI: 10.1039/c2lc40647k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In this paper, we report a novel method of droplet sensing in a two-plate digital microfluidic system (DMS) based on coplanar capacitance measurement. The total capacitance between the two adjacent electrodes on the lower plate depends on the position of the droplet. Both numerical and experimental results show that the capacitance is maximal at the midpoint between two electrodes. The value of maximum capacitance increases with the volume of the droplet. Further, the measured capacitance is a function of the gaps between the electrodes as well as the plates. This new method of droplet sensing adds to the functionality of DMSs by allowing single plate measurement.
Collapse
Affiliation(s)
- Biddut Bhattacharjee
- Okanagan School of Engineering, University of British Columbia Kelowna, BC V1V 1V7, Canada.
| | | |
Collapse
|
48
|
Martinez-Duarte R. Microfabrication technologies in dielectrophoresis applications--a review. Electrophoresis 2012; 33:3110-32. [PMID: 22941778 DOI: 10.1002/elps.201200242] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 06/10/2012] [Accepted: 06/11/2012] [Indexed: 11/12/2022]
Abstract
DEP is an established technique for particle manipulation. Although first demonstrated in the 1950s, it was not until the development of miniaturization techniques in the 1990s that DEP became a popular research field. The 1990s saw an explosion of DEP publications using microfabricated metal electrode arrays to sort a wide variety of cells. The concurrent development of microfluidics enabled devices for flow management and better understanding of the interaction between hydrodynamic and electrokinetic forces. Starting in the 2000s, alternative techniques have arisen to overcome common problems in metal-electrode DEP, such as electrode fouling, and to increase the throughput of the system. Insulator-based DEP and light-induced DEP are the most significant examples. Most recently, new 3D techniques such as carbon-electrode DEP, contactless DEP, and the use of doped PDMS have further simplified the fabrication process. The constant desire of the community to develop practical solutions has led to devices which are more user friendly, less expensive, and are capable of higher throughput. The state-of-the-art of fabricating DEP devices is critically reviewed in this work. The focus is on how different fabrication techniques can boost the development of practical DEP devices to be used in different settings such as clinical cell sorting and infection diagnosis, industrial food safety, and enrichment of particle populations for drug development.
Collapse
|
49
|
Abstract
In the present paper, we review and discuss current developments and challenges in the field of droplet-based microfluidics. This discussion includes an assessment of the basic fluid dynamics of segmented flows, material requirements, fundamental unit operations and how integration of functional components can be applied to specific biological problems.
Collapse
|
50
|
|