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Wei W, Wang Z, Wang B, He X, Wang Y, Bai Y, Yang Q, Pang W, Duan X. Acoustofluidic manipulation for submicron to nanoparticles. Electrophoresis 2024. [PMID: 38794970 DOI: 10.1002/elps.202400062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 04/25/2024] [Accepted: 04/29/2024] [Indexed: 05/27/2024]
Abstract
Particles, ranging from submicron to nanometer scale, can be broadly categorized into biological and non-biological types. Submicron-to-nanoscale bioparticles include various bacteria, viruses, liposomes, and exosomes. Non-biological particles cover various inorganic, metallic, and carbon-based particles. The effective manipulation of these submicron to nanoparticles, including their separation, sorting, enrichment, assembly, trapping, and transport, is a fundamental requirement for different applications. Acoustofluidics, owing to their distinct advantages, have emerged as a potent tool for nanoparticle manipulation over the past decade. Although recent literature reviews have encapsulated the evolution of acoustofluidic technology, there is a paucity of reports specifically addressing the acoustical manipulation of submicron to nanoparticles. This article endeavors to provide a comprehensive study of this topic, delving into the principles, apparatus, and merits of acoustofluidic manipulation of submicron to nanoparticles, and discussing the state-of-the-art developments in this technology. The discourse commences with an introduction to the fundamental theory of acoustofluidic control and the forces involved in nanoparticle manipulation. Subsequently, the working mechanism of acoustofluidic manipulation of submicron to nanoparticles is dissected into two parts, dominated by the acoustic wave field and the acoustic streaming field. A critical analysis of the advantages and limitations of different acoustofluidic platforms in nanoparticles control is presented. The article concludes with a summary of the challenges acoustofluidics face in the realm of nanoparticle manipulation and analysis, and a forecast of future development prospects.
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Affiliation(s)
- Wei Wei
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Zhaoxun Wang
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Bingnan Wang
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Xinyuan He
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Yaping Wang
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Yang Bai
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Qingrui Yang
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Wei Pang
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Xuexin Duan
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
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2
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Naquin TD, Canning AJ, Gu Y, Chen J, Naquin CM, Xia J, Lu B, Yang S, Koroza A, Lin K, Wang HN, Jeck WR, Lee LP, Vo-Dinh T, Huang TJ. Acoustic separation and concentration of exosomes for nucleotide detection: ASCENDx. SCIENCE ADVANCES 2024; 10:eadm8597. [PMID: 38457504 PMCID: PMC10923504 DOI: 10.1126/sciadv.adm8597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 02/05/2024] [Indexed: 03/10/2024]
Abstract
Efficient isolation and analysis of exosomal biomarkers hold transformative potential in biomedical applications. However, current methods are prone to contamination and require costly consumables, expensive equipment, and skilled personnel. Here, we introduce an innovative spaceship-like disc that allows Acoustic Separation and Concentration of Exosomes and Nucleotide Detection: ASCENDx. We created ASCENDx to use acoustically driven disc rotation on a spinning droplet to generate swift separation and concentration of exosomes from patient plasma samples. Integrated plasmonic nanostars on the ASCENDx disc enable label-free detection of enriched exosomes via surface-enhanced Raman scattering. Direct detection of circulating exosomal microRNA biomarkers from patient plasma samples by the ASCENDx platform facilitated a diagnostic assay for colorectal cancer with 95.8% sensitivity and 100% specificity. ASCENDx overcomes existing limitations in exosome-based molecular diagnostics and holds a powerful position for future biomedical research, precision medicine, and point-of-care medical diagnostics.
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Affiliation(s)
- Ty D. Naquin
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
| | - Aidan J. Canning
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Yuyang Gu
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
| | - Jianing Chen
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Chloe M. Naquin
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
| | - Jianping Xia
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
| | - Brandon Lu
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
| | - Shujie Yang
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
| | - Aleksandra Koroza
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
| | - Katherine Lin
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
| | - Hsin-Neng Wang
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - William R. Jeck
- Department of Pathology, Duke University Medical Center, Durham, NC 27708, USA
| | - Luke P. Lee
- Harvard Medical School, Harvard University; Renal Division and Division of Engineering in Medicine, Department of Medicine, Brigham and Women’s Hospital, Boston, MA 02115, USA
- Department of Bioengineering and Department of Electrical Engineering and Computer Science, University of California, Berkeley, Berkeley, CA 94720, USA
- Institute of Quantum Biophysics, Department of Biophysics, Sungkyunkwan University, Suwon, Gyeonggi-do, Korea
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul, Korea
| | - Tuan Vo-Dinh
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Tony Jun Huang
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
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3
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Lai TW, Tennakoon T, Chan KC, Liu CH, Chao CYH, Fu SC. The effect of microchannel height on the acoustophoretic motion of sub-micron particles. ULTRASONICS 2024; 136:107126. [PMID: 37553269 DOI: 10.1016/j.ultras.2023.107126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 06/19/2023] [Accepted: 07/26/2023] [Indexed: 08/10/2023]
Abstract
Acoustophoresis is an effective technique for particle manipulation. Acoustic radiation force scales with particle volume, enabling size separation. Yet, isolating sub-micron particles remains a challenge due to the acoustic streaming effect (ASE). While some studies confirmed the focusing ability of ASE, others reported continuous stirring effects. To investigate the parameters that influence ASE-induced particle motion in a microchannel, this study examined the effect of microchannel height and particle size. We employed standing surface acoustic wave (SSAW) to manipulate polystyrene particles suspended in the water-filled microchannel. The results show that ASE can direct particles as small as 0.31 µm in diameter to the centre of the streaming vortices, and increasing the channel height enhances the focusing effect. Smaller particles circulate in the streaming vortices continuously, with no movement towards the centres. We also discovered that when the channel height is at least 0.75 the fluid wavelength, particles transitioning from acoustic radiation-dominated to ASE-dominated share the same equilibrium position, which differs from the pressure nodes and the vortices' centres. The spatial distance between particles in different categories can lead to particle separation. Therefore, ASE is a potential alternative mechanism for sub-micron particle sorting when the channel height is accurately adjusted.
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Affiliation(s)
- Tsz Wai Lai
- Department of Building Environment and Energy Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Thilhara Tennakoon
- Department of Building Environment and Energy Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Ka Chung Chan
- Department of Building Environment and Energy Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Chun-Ho Liu
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Christopher Yu Hang Chao
- Department of Building Environment and Energy Engineering, The Hong Kong Polytechnic University, Hong Kong, China; Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Sau Chung Fu
- Department of Building Environment and Energy Engineering, The Hong Kong Polytechnic University, Hong Kong, China.
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4
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Kshetri KG, Nama N. Acoustophoresis around an elastic scatterer in a standing wave field. Phys Rev E 2023; 108:045102. [PMID: 37978594 DOI: 10.1103/physreve.108.045102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 09/11/2023] [Indexed: 11/19/2023]
Abstract
Acoustofluidic systems often employ prefabricated acoustic scatterers that perturb the imposed acoustic field to realize the acoustophoresis of immersed microparticles. We present a numerical study to investigate the time-averaged streaming and radiation force fields around a scatterer. Based on the streaming and radiation force field, we obtain the trajectories of the immersed microparticles with varying sizes and identify a critical transition size at which the motion of immersed microparticles in the vicinity of a prefabricated scatterer shifts from being streaming dominated to radiation dominated. We consider a range of acoustic frequencies to reveal that the critical transition size decreases with increasing frequency; this result explains the choice of acoustic frequencies in previously reported experimental studies. We also examine the impact of scatterer material and fluid properties on the streaming and radiation force fields, as well as on the critical transition size. Our results demonstrate that the critical transition size decreases with an increase in acoustic contrast factor: a nondimensional quantity that depends on material properties of the scatterer and the fluid. Our results provide a pathway to realize radiation force based manipulation of small particles by increasing the acoustic contrast factor of the scatterer, lowering the kinematic viscosity of the fluid, and increasing the acoustic frequency.
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Affiliation(s)
- Khemraj Gautam Kshetri
- Department of Mechanical & Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Nitesh Nama
- Department of Mechanical & Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
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5
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Chen X, Liu S, Shen M, Gao Z, Hu S, Zhao Y. Dielectrophoretic assembly and separation of particles and cells in continuous flow. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2023; 15:4485-4493. [PMID: 37610139 DOI: 10.1039/d3ay00666b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Dielectrophoretic (DEP) separation has been recognized as a practical tool in the separation of cells and particles for clinical diagnosis, the pharmaceutical industry and environmental monitoring. Assembly of particles and cells under DEP force is a common phenomenon and has an influence on their separation but has not been understood fully. Encouraged by these aspects, we developed a microfluidic device with a bipolar electrode array to investigate the assembly and separation of particles and cells at a large scale. First, we studied the assembly and evolution mechanisms of particles of one type under an AC electric field. Then, we investigated the interaction and assembly of multiple particles with dissimilar properties under DEP force. Depending on the development of microfluidic devices, we visualize the assembly process of yeast cells at the electrode rims and of polystyrene particles at the channel centers, and explore the influence of pearl chain formation on their separation. With increasing flow velocity from 288 to 720 μL h-1, the purity of 5 μm polystyrene particles surpasses 94.9%. Furthermore, we studied the DEP response of Scenedesmus sp. and C. vulgaris, and explored the influence of cell chains on the isolation of C. vulgaris. The purity of Scenedesmus sp. and C. vulgaris witnessed a decrease from 95.7% to 90.8% when the flow rate increased from 288 to 864 μL h-1. Finally, we investigated the extension of the electric field under chains of Oocystis sp. at the electrode rims by studying chain formation and capture of C. vulgaris, and studied its effect on cell chain length, recovered cell purity and cell concentration. When chains of Oocystis sp. were formed, the purity of C. vulgaris kept unchanged and the concentration decreased from 2793 cells per μL to 2039 cells per μL. This work demonstrates continuous DEP-based assembly and separation of particles and cells, which facilitates high-efficiency isolation of targeted cells.
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Affiliation(s)
- Xiaoming Chen
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, PR China.
- Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao, 066004, PR China
| | - Shun Liu
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, PR China.
- Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao, 066004, PR China
| | - Mo Shen
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, PR China.
- Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao, 066004, PR China
| | - Ziwei Gao
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, PR China.
| | - Sheng Hu
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, PR China.
- Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao, 066004, PR China
| | - Yong Zhao
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, PR China.
- Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao, 066004, PR China
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Edthofer A, Novotny J, Lenshof A, Laurell T, Baasch T. Acoustofluidic Properties of Polystyrene Microparticles. Anal Chem 2023. [PMID: 37363950 DOI: 10.1021/acs.analchem.3c01156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
Acoustophoresis has become a powerful tool to separate microparticles and cells, based on their material and biophysical properties, and is gaining popularity in clinical and biomedical research. One major application of acoustophoresis is to measure the compressibility of cells and small organisms, which is related to their contents. The cell compressibility can be extracted from the acoustic mobility, which is the main output of acoustic migration experiments, if the material properties and sizes of reference particles, the size of the cells, and the surrounding medium are known. Accurate methods to measure and calibrate the acoustic energy density in acoustophoresis systems are therefore critical. In this Perspective, polystyrene microparticles have become the most commonly used reference particles in acoustophoresis, due to their similar biophysical properties to cells. We utilized a two-step focusing method to measure the relative acoustic mobility of polystyrene beads of various sizes and colors and present a quantitative analysis of the variation in acousto-mechanical properties of polystyrene microparticles, showing a large spread in their material properties. A variation of more than 25% between different particle types was found. Thus, care is required when relying on polystyrene particles as a reference when characterizing acoustofluidics systems or acousto-mechanical properties of cells.
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Affiliation(s)
- Alexander Edthofer
- Department of Biomedical Engineering, Lund University, 223 63 Lund, Sweden
| | - Jakub Novotny
- Department of Bioanalytical Instrumentation, Institute of Analytical Chemistry of the CAS, 602 00 Brno, Czech Republic
| | - Andreas Lenshof
- Department of Biomedical Engineering, Lund University, 223 63 Lund, Sweden
| | - Thomas Laurell
- Department of Biomedical Engineering, Lund University, 223 63 Lund, Sweden
| | - Thierry Baasch
- Department of Biomedical Engineering, Lund University, 223 63 Lund, Sweden
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7
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Winckelmann BG, Bruus H. Acoustic radiation force on a spherical thermoviscous particle in a thermoviscous fluid including scattering and microstreaming. Phys Rev E 2023; 107:065103. [PMID: 37464611 DOI: 10.1103/physreve.107.065103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Accepted: 05/12/2023] [Indexed: 07/20/2023]
Abstract
We derive general analytical expressions for the time-averaged acoustic radiation force on a small spherical particle suspended in a fluid and located in an axisymmetric incident acoustic wave. We treat the cases of the particle being either an elastic solid or a fluid particle. The effects of particle vibrations, acoustic scattering, acoustic microstreaming, heat conduction, and temperature-dependent fluid viscosity are all included in the theory. Acoustic streaming inside the particle is also taken into account for the case of a fluid particle. No restrictions are placed on the widths of the viscous and thermal boundary layers relative to the particle radius. We compare the resulting acoustic radiation force with that obtained from previous theories in the literature, and we identify limits, where the theories agree, and specific cases of particle and fluid materials, where qualitative or significant quantitative deviations between the theories arise.
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Affiliation(s)
- Bjørn G Winckelmann
- Department of Physics, Technical University of Denmark, DTU Physics Building 309, DK-2800 Kongens Lyngby, Denmark
| | - Henrik Bruus
- Department of Physics, Technical University of Denmark, DTU Physics Building 309, DK-2800 Kongens Lyngby, Denmark
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8
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Fakhfouri A, Colditz M, Devendran C, Ivanova K, Jacob S, Neild A, Winkler A. Fully Microfabricated Surface Acoustic Wave Tweezer for Collection of Submicron Particles and Human Blood Cells. ACS APPLIED MATERIALS & INTERFACES 2023; 15:24023-24033. [PMID: 37188328 PMCID: PMC10215297 DOI: 10.1021/acsami.3c00537] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 04/25/2023] [Indexed: 05/17/2023]
Abstract
Precise manipulation of (sub)micron particles is key for the preparation, enrichment, and quality control in many biomedical applications. Surface acoustic waves (SAW) hold tremendous promise for manipulation of (bio)particles at the micron to nanoscale ranges. In commonly used SAW tweezers, particle manipulation relies on the direct acoustic radiation effect whose superior performance fades rapidly when progressing from micron to nanoscale particles due to the increasing dominance of a second order mechanism, termed acoustic streaming. Through reproducible and high-precision realization of stiff microchannels to reliably actuate the microchannel cross-section, here we introduce an approach that allows the otherwise competing acoustic streaming to complement the acoustic radiation effect. The synergetic effect of both mechanisms markedly enhances the manipulation of nanoparticles, down to 200 nm particles, even at relatively large wavelength (300 μm). Besides spherical particles ranging from 0.1 to 3 μm, we show collections of cells mixed with different sizes and shapes inherently existing in blood including erythrocytes, leukocytes, and thrombocytes.
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Affiliation(s)
| | - Melanie Colditz
- Leibniz-IFW
Dresden, Helmholtzstr.
20, 01069 Dresden, Germany
| | - Citsabehsan Devendran
- Department
of Mechanical and Aerospace Engineering Monash University, Clayton, Victoria 3800, Australia
| | | | - Stefan Jacob
- Physikalisch-Technische
Bundesanstalt, Bundesallee
100, 38116, Brunswick, Germany
| | - Adrian Neild
- Department
of Mechanical and Aerospace Engineering Monash University, Clayton, Victoria 3800, Australia
| | - Andreas Winkler
- Leibniz-IFW
Dresden, Helmholtzstr.
20, 01069 Dresden, Germany
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9
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Açıkgöz HN, Karaman A, Şahin MA, Çaylan ÖR, Büke GC, Yıldırım E, Eroğlu İC, Erson-Bensan AE, Çetin B, Özer MB. Assessment of silicon, glass, FR4, PDMS and PMMA as a chip material for acoustic particle/cell manipulation in microfluidics. ULTRASONICS 2023; 129:106911. [PMID: 36528906 DOI: 10.1016/j.ultras.2022.106911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 10/13/2022] [Accepted: 11/06/2022] [Indexed: 06/17/2023]
Abstract
In the present study, the capabilities of different chip materials for acoustic particle manipulation have been assessed with the same microfluidic device architecture, under the same actuator and flow conditions. Silicon, glass, epoxy with fiberglass filling (FR4), polydimethylsiloxane (PDMS) and polymethyl methacrylate (PMMA) are considered as chip materials. The acoustophoretic chips in this study were manufactured with four different fabrication methods: plasma etching, chemical etching, micromachining and molding. A novel chip material, FR4, has been employed as a microfluidic chip material in acoustophoretic particle manipulation for the first time in literature, which combines the ease of manufacturing of polymer materials with improved acoustic performance. The acoustic particle manipulation performance is evaluated through acoustophoretic focusing experiments with 2μm and 12μm polystyrene microspheres and cultured breast cancer cell line (MDA-MB-231). Unlike the common approach in the literature, the piezoelectric materials were actuated with partitioned cross-polarized electrodes which allowed effective actuation of different family of chip materials. Different from previous studies, this study evaluates the performance of each acoustophoretic device through the perspective of synchronization of electrical, vibrational and acoustical resonances, considers the thermal performance of the chip materials with their effects on cell viability as well as manufacturability and scalability of their fabrication methods. We believe our study is an essential work towards the commercialization of acoustophoretic devices since it brings a critical understanding of the effect of chip material on device performance as well as the cost of achieving that performance.
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Affiliation(s)
- Hande N Açıkgöz
- Microfluidics & Lab-on-a-chip Research Group, Mech. Eng. Department, Bilkent University, Ankara 06800, Turkey; UNAM - National Nanotechnology Research Center and Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Turkey
| | - Alara Karaman
- Mech. Eng. Department, Middle East Technical University 06800 Ankara, Turkey
| | - M Akif Şahin
- Microfluidics & Lab-on-a-chip Research Group, Mech. Eng. Department, Bilkent University, Ankara 06800, Turkey; Mech. Eng. Department, Middle East Technical University 06800 Ankara, Turkey
| | - Ömer R Çaylan
- Department Materials Sci.Nanotech. Eng., TOBB Uni. Econ. Tech., 06510 Ankara, Turkey
| | - Göknur C Büke
- Department Materials Sci.Nanotech. Eng., TOBB Uni. Econ. Tech., 06510 Ankara, Turkey
| | - Ender Yıldırım
- Mech. Eng. Department, Middle East Technical University 06800 Ankara, Turkey
| | - İrem C Eroğlu
- Department Biological Sciences, Middle East Technical University, 06800 Ankara, Turkey
| | - A Elif Erson-Bensan
- Department Biological Sciences, Middle East Technical University, 06800 Ankara, Turkey
| | - Barbaros Çetin
- Microfluidics & Lab-on-a-chip Research Group, Mech. Eng. Department, Bilkent University, Ankara 06800, Turkey; UNAM - National Nanotechnology Research Center and Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Turkey
| | - M Bülent Özer
- Mech. Eng. Department, Middle East Technical University 06800 Ankara, Turkey.
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10
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Hettiarachchi S, Cha H, Ouyang L, Mudugamuwa A, An H, Kijanka G, Kashaninejad N, Nguyen NT, Zhang J. Recent microfluidic advances in submicron to nanoparticle manipulation and separation. LAB ON A CHIP 2023; 23:982-1010. [PMID: 36367456 DOI: 10.1039/d2lc00793b] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Manipulation and separation of submicron and nanoparticles are indispensable in many chemical, biological, medical, and environmental applications. Conventional technologies such as ultracentrifugation, ultrafiltration, size exclusion chromatography, precipitation and immunoaffinity capture are limited by high cost, low resolution, low purity or the risk of damage to biological particles. Microfluidics can accurately control fluid flow in channels with dimensions of tens of micrometres. Rapid microfluidics advancement has enabled precise sorting and isolating of nanoparticles with better resolution and efficiency than conventional technologies. This paper comprehensively studies the latest progress in microfluidic technology for submicron and nanoparticle manipulation. We first summarise the principles of the traditional techniques for manipulating nanoparticles. Following the classification of microfluidic techniques as active, passive, and hybrid approaches, we elaborate on the physics, device design, working mechanism and applications of each technique. We also compare the merits and demerits of different microfluidic techniques and benchmark them with conventional technologies. Concurrently, we summarise seven standard post-separation detection techniques for nanoparticles. Finally, we discuss current challenges and future perspectives on microfluidic technology for nanoparticle manipulation and separation.
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Affiliation(s)
- Samith Hettiarachchi
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia.
| | - Haotian Cha
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia.
| | - Lingxi Ouyang
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia.
| | | | - Hongjie An
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia.
| | - Gregor Kijanka
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia.
| | - Navid Kashaninejad
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia.
| | - Nam-Trung Nguyen
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia.
| | - Jun Zhang
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia.
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11
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Zhou Y. The Effect of Microchannel Cavity on the Bulk Acoustic Wave-Induced Acoustofluidics: Numerical Investigation. JOURNAL OF NANOFLUIDS 2022. [DOI: 10.1166/jon.2022.1893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Acoustofluidics is emerging as an effective approach to manipulating microparticles and cells no matter their optical, electrical, and magnetic properties and no requirement of pre-processing. Standing field in a microfluidic channel produced by a bulk acoustic wave (BAW) could accumulate
the microparticles at the plane of the pressure node. In order to further accumulate them from a plane (2D) to a line (1D), a new strategy without significant change of the systematic setup (i.e., adding another orthogonal standing field) was proposed and evaluated numerically in a full-sized
model. Concave cavity on the conventional rectangular microchannel leads to a slight increase of the maximum acoustic pressure and distortion of the wavefront, but two more vortexes close to the edge of the bottom cavity and directional acoustic radiation forces in the middle line of the microchannel
(the upper part pointing downwards while the lower part upwards). Subsequently, most of the microparticles are accumulated in a very small region in the middle line of the microchannel. The effect of the cavity geometry on such a novel phenomenon was investigated. With the increase of the
diameter of the cavity from 170 μm to 260 μm, the resonant frequency of the microchannel, the maximum acoustic pressure, and the maximum acoustic streaming velocity increased by 13%, 78%, and 7.1 fold, respectively. When shifting the center of the cavity, the position of
1D accumulated microparticles could be changed correspondingly. In summary, the characteristics of acoustofluidics are highly dependent on the microchannel geometry. Microparticle accumulation with a significant reduction to one dimension using only one acoustic standing field is theoretically
possible by introducing an appropriate concave cavity in the conventional rectangular microchannel.
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Affiliation(s)
- Yufeng Zhou
- State Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China; Chongqing State Laboratory of Biomedical Engineering, Chongqing Medical University, Chongqing,
400016, China
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12
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Goering C, Dual J. Measuring the effects of a pulsed excitation on the buildup of acoustic streaming and the acoustic radiation force utilizing an optical tweezer. Phys Rev E 2022; 105:055103. [PMID: 35706167 DOI: 10.1103/physreve.105.055103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 04/28/2022] [Indexed: 06/15/2023]
Abstract
Pulsed excitations of piezoelectric transducers affect during the buildup the force contributions from acoustic streaming (AS) and the acoustic radiation force (ARF) to the total force in a standing pressure wave differently. We find with an optical tweezer as measuring instrument that during the first 120 000 excitation periods and across different pulsing frequencies, the AS-induced displacement is on average less than 20% of its nonpulsed value for a duty cycle of 50%, whereas the ARF-induced displacement is around 50%. These findings show that a pulsed excitation can be a tool for reducing AS compared to the ARF.
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Affiliation(s)
- Christoph Goering
- ETH Zurich, Insitute for Mechanical Systems, Leonhardstr. 21, 8092 Zurich, Switzerland
| | - Jürg Dual
- ETH Zurich, Insitute for Mechanical Systems, Leonhardstr. 21, 8092 Zurich, Switzerland
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13
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Farkas E, Tarr R, Gerecsei T, Saftics A, Kovács KD, Stercz B, Domokos J, Peter B, Kurunczi S, Szekacs I, Bonyár A, Bányai A, Fürjes P, Ruszkai-Szaniszló S, Varga M, Szabó B, Ostorházi E, Szabó D, Horvath R. Development and In-Depth Characterization of Bacteria Repellent and Bacteria Adhesive Antibody-Coated Surfaces Using Optical Waveguide Biosensing. BIOSENSORS 2022; 12:bios12020056. [PMID: 35200317 PMCID: PMC8869200 DOI: 10.3390/bios12020056] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 01/07/2022] [Accepted: 01/13/2022] [Indexed: 05/10/2023]
Abstract
Bacteria repellent surfaces and antibody-based coatings for bacterial assays have shown a growing demand in the field of biosensors, and have crucial importance in the design of biomedical devices. However, in-depth investigations and comparisons of possible solutions are still missing. The optical waveguide lightmode spectroscopy (OWLS) technique offers label-free, non-invasive, in situ characterization of protein and bacterial adsorption. Moreover, it has excellent flexibility for testing various surface coatings. Here, we describe an OWLS-based method supporting the development of bacteria repellent surfaces and characterize the layer structures and affinities of different antibody-based coatings for bacterial assays. In order to test nonspecific binding blocking agents against bacteria, OWLS chips were coated with bovine serum albumin (BSA), I-block, PAcrAM-g-(PMOXA, NH2, Si), (PAcrAM-P) and PLL-g-PEG (PP) (with different coating temperatures), and subsequent Escherichia coli adhesion was monitored. We found that the best performing blocking agents could inhibit bacterial adhesion from samples with bacteria concentrations of up to 107 cells/mL. Various immobilization methods were applied to graft a wide range of selected antibodies onto the biosensor's surface. Simple physisorption, Mix&Go (AnteoBind) (MG) films, covalently immobilized protein A and avidin-biotin based surface chemistries were all fabricated and tested. The surface adsorbed mass densities of deposited antibodies were determined, and the biosensor;s kinetic data were evaluated to divine the possible orientations of the bacteria-capturing antibodies and determine the rate constants and footprints of the binding events. The development of affinity layers was supported by enzyme-linked immunosorbent assay (ELISA) measurements in order to test the bacteria binding capabilities of the antibodies. The best performance in the biosensor measurements was achieved by employing a polyclonal antibody in combination with protein A-based immobilization and PAcrAM-P blocking of nonspecific binding. Using this setting, a surface sensitivity of 70 cells/mm2 was demonstrated.
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Affiliation(s)
- Eniko Farkas
- Centre for Energy Research, Nanobiosensorics Laboratory, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (R.T.); (T.G.); (A.S.); (K.D.K.); (B.P.); (S.K.); (I.S.)
| | - Robert Tarr
- Centre for Energy Research, Nanobiosensorics Laboratory, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (R.T.); (T.G.); (A.S.); (K.D.K.); (B.P.); (S.K.); (I.S.)
- Department of Electronics Technology, Faculty of Electrical Engineering and Informatics, Budapest University of Technology and Economics, 1111 Budapest, Hungary;
| | - Tamás Gerecsei
- Centre for Energy Research, Nanobiosensorics Laboratory, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (R.T.); (T.G.); (A.S.); (K.D.K.); (B.P.); (S.K.); (I.S.)
- Department of Biological Physics, Eötvös Loránd University, 1117 Budapest, Hungary
| | - Andras Saftics
- Centre for Energy Research, Nanobiosensorics Laboratory, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (R.T.); (T.G.); (A.S.); (K.D.K.); (B.P.); (S.K.); (I.S.)
| | - Kinga Dóra Kovács
- Centre for Energy Research, Nanobiosensorics Laboratory, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (R.T.); (T.G.); (A.S.); (K.D.K.); (B.P.); (S.K.); (I.S.)
- Department of Biological Physics, Eötvös Loránd University, 1117 Budapest, Hungary
| | - Balazs Stercz
- Institute of Medical Microbiology, Semmelweis University, 1089 Budapest, Hungary; (B.S.); (J.D.); (E.O.); (D.S.)
| | - Judit Domokos
- Institute of Medical Microbiology, Semmelweis University, 1089 Budapest, Hungary; (B.S.); (J.D.); (E.O.); (D.S.)
| | - Beatrix Peter
- Centre for Energy Research, Nanobiosensorics Laboratory, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (R.T.); (T.G.); (A.S.); (K.D.K.); (B.P.); (S.K.); (I.S.)
| | - Sandor Kurunczi
- Centre for Energy Research, Nanobiosensorics Laboratory, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (R.T.); (T.G.); (A.S.); (K.D.K.); (B.P.); (S.K.); (I.S.)
| | - Inna Szekacs
- Centre for Energy Research, Nanobiosensorics Laboratory, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (R.T.); (T.G.); (A.S.); (K.D.K.); (B.P.); (S.K.); (I.S.)
| | - Attila Bonyár
- Department of Electronics Technology, Faculty of Electrical Engineering and Informatics, Budapest University of Technology and Economics, 1111 Budapest, Hungary;
| | - Anita Bányai
- Centre for Energy Research, Microsystems Lab, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (A.B.); (P.F.)
| | - Péter Fürjes
- Centre for Energy Research, Microsystems Lab, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (A.B.); (P.F.)
| | | | - Máté Varga
- 77 Elektronika Ltd., 1116 Budapest, Hungary; (S.R.-S.); (M.V.); (B.S.)
| | - Barnabás Szabó
- 77 Elektronika Ltd., 1116 Budapest, Hungary; (S.R.-S.); (M.V.); (B.S.)
| | - Eszter Ostorházi
- Institute of Medical Microbiology, Semmelweis University, 1089 Budapest, Hungary; (B.S.); (J.D.); (E.O.); (D.S.)
| | - Dóra Szabó
- Institute of Medical Microbiology, Semmelweis University, 1089 Budapest, Hungary; (B.S.); (J.D.); (E.O.); (D.S.)
| | - Robert Horvath
- Centre for Energy Research, Nanobiosensorics Laboratory, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (R.T.); (T.G.); (A.S.); (K.D.K.); (B.P.); (S.K.); (I.S.)
- Correspondence:
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14
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Zhou Y. Effect of microchannel protrusion on the bulk acoustic wave-induced acoustofluidics: numerical investigation. Biomed Microdevices 2021; 24:7. [PMID: 34964071 DOI: 10.1007/s10544-021-00608-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/11/2021] [Indexed: 11/30/2022]
Abstract
Acoustofluidics inside the microchannel has already found its wide applications recently. Acoustic streaming and radiation force are two underlying mechanisms that determine the trajectory of microparticles and cells in the manipulation. Critical particle size of viscous effects is found to be about 1.6 µm in the conventional rectangular microchannel (W × H = 380 m × 160 m) at the frequency of 2 MHz, below which the acoustic streaming dominants, and is independent of the driving voltage. In order to effectively adjust such a critical size, a approach is proposed and evaluated numerically to enhance the acoustic streaming by adding some protrusions (i.e., in the shape of a wedge, rod, half-ellipse) to the middle of the top or bottom wall. It is found that the resonant frequency and acoustic pressure will decrease and the acoustic streaming velocity will increase significantly, respectively, with the increase of protrusion height (up to 30 µm while keeping the width the same as 8 µm). Subsequently, trajectory motion patterns of microparticles have apparent changes in comparison to those inside the rectangular microchannel, and acoustic streaming can even dominate the motion of large microparticles (i.e., 10 µm). As a result, the critical particle size could be increased up to 72.5 µm. Furthermore, different protrusion shapes (i.e., wedge, rod, half-ellipse) on the top wall were compared. The sharpness of protrusion at its tip seems to determine the acoustic streaming velocity. The wedge attached to the bottom wall had higher resonant frequency and lower acoustic streaming velocity compared with the top wedge in the same dimension. The patterns of acoustic streaming and microparticle trajectory motion in the microchannel with dual wedges on the top and bottom walls are not the superposition of those of the top and bottom wedge individually. In summary, the geometry of the microchannel has a significant effect on the induced acoustofluidics by the bulk acoustic waves. A much larger acoustic streaming velocity is produced at the tip of the protrusion to change the critical size of microparticles between acoustic streaming and radiation force. It suggests that more applications of acoustofluidics (i.e., mixing and sonoporation) to microparticles and cells in various sizes are feasible by designing an appropriate geometry of the microchannel.
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Affiliation(s)
- Yufeng Zhou
- State Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China. .,Chongqing Key Laboratory of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China.
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15
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Ugawa M, Lee H, Baasch T, Lee M, Kim S, Jeong O, Choi YH, Sohn D, Laurell T, Ota S, Lee S. Reduced acoustic resonator dimensions improve focusing efficiency of bacteria and submicron particles. Analyst 2021; 147:274-281. [PMID: 34889326 DOI: 10.1039/d1an01891d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In this study, we demonstrate an acoustofluidic device that enables single-file focusing of submicron particles and bacteria using a two-dimensional (2D) acoustic standing wave. The device consists of a 100 μm × 100 μm square channel that supports 2D particle focusing in the channel center at an actuation frequency of 7.39 MHz. This higher actuation frequency compared with conventional bulk acoustic systems enables radiation-force-dominant motion of submicron particles and overcomes the classical size limitation (≈2 μm) of acoustic focusing. We present acoustic radiation force-based focusing of particles with diameters less than 0.5 μm at a flow rate of 12 μL min-1, and 1.33 μm particles at flow rates up to 80 μL min-1. The device focused 0.25 μm particles by the 2D acoustic radiation force while undergoing a channel cross-section centered, single-vortex acoustic streaming. A suspension of bacteria was also investigated to evaluate the biological relevance of the device, which demonstrated the alignment of bacteria in the channel at a flow rate of up to 20 μL min-1. The developed acoustofluidic device can align submicron particles within a narrow flow stream in a highly robust manner, validating its use as a flow-through focusing chamber to perform high-throughput and accurate flow cytometry of submicron objects.
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Affiliation(s)
- Masashi Ugawa
- RCAST, The University of Tokyo, 153-8904, Tokyo, Japan.
| | - Hoyeon Lee
- Department of Chemistry, Research Institute for Convergence of Basic Science, Hanyang University, Seoul, 04763, Korea
| | - Thierry Baasch
- Department of Biomedical engineering, Lund University, 22363, Lund, Sweden
| | - Minho Lee
- School of integrative engineering, Chung-Ang University, Seoul, 06974, Korea
| | - Soyun Kim
- Convergence Research Institute, Korea University, 02841, Seoul, Korea.,PCL Inc., 05854, Seoul, Korea
| | - OkChan Jeong
- Department of Biomedical Engineering, Inje University, Gimhae-si, 50834, Korea
| | | | - Daewon Sohn
- Department of Chemistry, Research Institute for Convergence of Basic Science, Hanyang University, Seoul, 04763, Korea
| | - Thomas Laurell
- Department of Biomedical engineering, Lund University, 22363, Lund, Sweden
| | - Sadao Ota
- RCAST, The University of Tokyo, 153-8904, Tokyo, Japan.
| | - SangWook Lee
- RCAST, The University of Tokyo, 153-8904, Tokyo, Japan. .,Bio-health Product Research Center, Inje University, Gimhae-si, 50834, Korea
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16
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Gerlt MS, Ruppen P, Leuthner M, Panke S, Dual J. Acoustofluidic medium exchange for preparation of electrocompetent bacteria using channel wall trapping. LAB ON A CHIP 2021; 21:4487-4497. [PMID: 34668506 PMCID: PMC8577197 DOI: 10.1039/d1lc00406a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 10/13/2021] [Indexed: 06/02/2023]
Abstract
Comprehensive integration of process steps into a miniaturised version of synthetic biology workflows remains a crucial task in automating the design of biosystems. However, each of these process steps has specific demands with respect to the environmental conditions, including in particular the composition of the surrounding fluid, which makes integration cumbersome. As a case in point, transformation, i.e. reprogramming of bacteria by delivering exogenous genetic material (such as DNA) into the cytoplasm, is a key process in molecular engineering and modern biotechnology in general. Transformation is often performed by electroporation, i.e. creating pores in the membrane using electric shocks in a low conductivity environment. However, cell preparation for electroporation can be cumbersome as it requires the exchange of growth medium (high-conductivity) for low-conductivity medium, typically performed via multiple time-intensive centrifugation steps. To simplify and miniaturise this step, we developed an acoustofluidic device capable of trapping the bacterium Escherichia coli non-invasively for subsequent exchange of medium, which is challenging in acoustofluidic devices due to detrimental acoustic streaming effects. With an improved etching process, we were able to produce a thin wall between two microfluidic channels, which, upon excitation, can generate streaming fields that complement the acoustic radiation force and therefore can be utilised for trapping of bacteria. Our novel design robustly traps Escherichia coli at a flow rate of 10 μL min-1 and has a cell recovery performance of 47 ± 3% after washing the trapped cells. To verify that the performance of the medium exchange device is sufficient, we tested the electrocompetence of the recovered cells in a standard transformation procedure and found a transformation efficiency of 8 × 105 CFU per μg of plasmid DNA. Our device is a low-volume alternative to centrifugation-based methods and opens the door for miniaturisation of a plethora of microbiological and molecular engineering protocols.
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Affiliation(s)
- M S Gerlt
- Mechanics and Experimental Dynamics, Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology (ETH Zurich), Tannenstrasse 3, CH-8092 Zurich, Switzerland.
| | - P Ruppen
- Bioprocess Laboratory, Department of Biosystems Science and Engineering, Swiss Federal Institute of Technology (ETH Zurich), Mattenstrasse 26, CH-4058 Basel, Switzerland.
- NCCR Molecular Systems Engineering, BPR 1095, Mattenstrasse 24a, CH-4058 Basel, Switzerland
| | - M Leuthner
- Mechanics and Experimental Dynamics, Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology (ETH Zurich), Tannenstrasse 3, CH-8092 Zurich, Switzerland.
| | - S Panke
- Bioprocess Laboratory, Department of Biosystems Science and Engineering, Swiss Federal Institute of Technology (ETH Zurich), Mattenstrasse 26, CH-4058 Basel, Switzerland.
- NCCR Molecular Systems Engineering, BPR 1095, Mattenstrasse 24a, CH-4058 Basel, Switzerland
| | - J Dual
- Mechanics and Experimental Dynamics, Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology (ETH Zurich), Tannenstrasse 3, CH-8092 Zurich, Switzerland.
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17
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Novotny J, Lenshof A, Laurell T. Acoustofluidic platforms for particle manipulation. Electrophoresis 2021; 43:804-818. [PMID: 34719049 DOI: 10.1002/elps.202100291] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/20/2021] [Accepted: 10/25/2021] [Indexed: 12/12/2022]
Abstract
There is an increasing interest in acoustics for microfluidic applications. This field, commonly known as acoustofluidics involves the interaction of ultrasonic standing waves with fluids and dispersed microparticles. The combination of microfluidics and the so-called acoustic standing waves (ASWs) led to the development of integrated systems for contact-less on-chip cell and particle manipulation where it is possible to move and spatially localize these particles based on the different acoustophysical properties. While it was initially suggested that the acoustic forces could be harmful to the cells and could impact cell viability, proliferation, or function via phenotypic or even genotypic changes, further studies disproved such claims. This review is summarizing some interesting applications of acoustofluidics in the manipulations of biomaterials, such as cells or subcellular vesicles, in works published mainly within the last 5 years.
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Affiliation(s)
- Jakub Novotny
- Institute of Analytical Chemistry, Czech Academy of Sciences, Brno, Czech Republic
| | - Andreas Lenshof
- Department of Biomedical Engineering, Lund University, Lund, Sweden
| | - Thomas Laurell
- Department of Biomedical Engineering, Lund University, Lund, Sweden
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18
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Focalization Performance Study of a Novel Bulk Acoustic Wave Device. NANOMATERIALS 2021; 11:nano11102630. [PMID: 34685065 PMCID: PMC8541289 DOI: 10.3390/nano11102630] [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: 07/26/2021] [Revised: 09/27/2021] [Accepted: 09/28/2021] [Indexed: 12/04/2022]
Abstract
This work illustrates focalization performances of a silicon-based bulk acoustic wave device applied for the separation of specimens owing to micrometric dimensions. Samples are separated in the microfluidic channel by the presence of an acoustic field, which focalizes particles or cells according to their mechanical properties compared to the surrounded medium ones. Design and fabrication processes are reported, followed by focalization performance tests conducted either with synthetic particles or cells. High focalization performances occurred at different microparticle concentrations. In addition, preliminary tests carried out with HL-60 cells highlighted an optimal separation performance at a high flow rate and when cells are mixed with micro and nanoparticles without affecting device focalization capabilities. These encouraging results showed how this bulk acoustic wave device could be exploited to develop a diagnostic tool for early diagnosis or some specific target therapies by separating different kinds of cells or biomarkers possessing different mechanical properties such as shapes, sizes and densities.
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19
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Kleiber A, Kraus D, Henkel T, Fritzsche W. Review: tomographic imaging flow cytometry. LAB ON A CHIP 2021; 21:3655-3666. [PMID: 34514484 DOI: 10.1039/d1lc00533b] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Within the last decades, conventional flow cytometry (FC) has evolved as a powerful measurement method in clinical diagnostics, biology, life sciences and healthcare. Imaging flow cytometry (IFC) extends the power of traditional FC by adding high resolution optical and spectroscopic information. However, the conventional IFC only provides a 2D projection of a 3D object. To overcome this limitation, tomographic imaging flow cytometry (tIFC) was developed to access 3D information about the target particles. The goal of tIFC is to visualize surfaces and internal structures in a holistic way. This review article gives an overview of the past and current developments in tIFC.
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Affiliation(s)
- Andreas Kleiber
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, D-07745 Jena, Germany
| | - Daniel Kraus
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, D-07745 Jena, Germany
| | - Thomas Henkel
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, D-07745 Jena, Germany
| | - Wolfgang Fritzsche
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, D-07745 Jena, Germany
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20
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Jannesar EA, Hamzehpour H. Acoustic tweezing of microparticles in microchannels with sinusoidal cross sections. Sci Rep 2021; 11:17902. [PMID: 34504163 PMCID: PMC8429439 DOI: 10.1038/s41598-021-97132-7] [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: 05/29/2020] [Accepted: 08/18/2021] [Indexed: 01/03/2023] Open
Abstract
Acoustic tweezing of bioparticles has distinct advantages over other manipulation methods such as electrophoresis or magnetophoresis in biotechnological applications. This manipulation method guarantees the viability of the bio-particles during and after the process. In this paper, the effects of sinusoidal boundaries of a microchannel on acoustophoretic manipulation of microparticles are studied. Our results show that while top and bottom walls are vertically actuated at the horizontal half-wave resonance frequency, a large mono-vortex appears, which is never achievable in a rectangular geometry with flat walls and one-dimensional oscillations. The drag force caused by such a vortex in combination with the tilted acoustic radiation force leads to trapping and micromixing of microparticles with diameters larger and smaller than the critical size, respectively. Simulation results in this paper show that efficient particle trapping occurs at the intermediate sinusoidal boundary amplitudes. It is also indicated that in a square-sinusoidal geometry there are two strong vortices, instead of one vortex. Sub-micrometer particles tend to be trapped dramatically faster in such a geometry than in the rectangular-sinusoidal ones.
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Affiliation(s)
- Elnaz Attar Jannesar
- Department of Physics, K.N. Toosi University of Technology, Tehran, 15875-4416, Iran
| | - Hossein Hamzehpour
- Department of Physics, K.N. Toosi University of Technology, Tehran, 15875-4416, Iran. .,School of Physics, Institute for Research in Fundamental Sciences (IPM), Tehran, 19395-5531, Iran.
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21
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Geng P, Li C, Ji X, Dong S. Numerical simulation of microfluidic mixing by ultrasonic-induced acoustic streaming. J DISPER SCI TECHNOL 2021. [DOI: 10.1080/01932691.2020.1775638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Pengfei Geng
- Department of Power Engineering, North China Electric Power University, Baoding, China
| | - Chunxi Li
- Department of Power Engineering, North China Electric Power University, Baoding, China
| | - Xiangyong Ji
- Department of Power Engineering, North China Electric Power University, Baoding, China
| | - Shuai Dong
- Department of Power Engineering, North China Electric Power University, Baoding, China
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22
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Qiu W, Joergensen JH, Corato E, Bruus H, Augustsson P. Fast Microscale Acoustic Streaming Driven by a Temperature-Gradient-Induced Nondissipative Acoustic Body Force. PHYSICAL REVIEW LETTERS 2021; 127:064501. [PMID: 34420350 PMCID: PMC7615609 DOI: 10.1103/physrevlett.127.064501] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
We study acoustic streaming in liquids driven by a nondissipative acoustic body force created by light-induced temperature gradients. This thermoacoustic streaming produces a velocity amplitude nearly 100 times higher than the boundary-driven Rayleigh streaming and the Rayleigh-Bénard convection at a temperature gradient of 10 K/mm in the channel. The Rayleigh streaming is altered by the acoustic body force at a temperature gradient of only 0.5 K/mm. The thermoacoustic streaming allows for modular flow control and enhanced heat transfer at the microscale. Our study provides the groundwork for studying microscale acoustic streaming coupled with temperature fields.
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Affiliation(s)
- Wei Qiu
- Department of Biomedical Engineering, Lund University, Ole Römers väg 3, 22363 Lund, Sweden
| | - Jonas Helboe Joergensen
- Department of Physics, Technical University of Denmark, DTU Physics Building 309, DK-2800 Kongens Lyngby, Denmark
| | - Enrico Corato
- Department of Biomedical Engineering, Lund University, Ole Römers väg 3, 22363 Lund, Sweden
| | - Henrik Bruus
- Department of Physics, Technical University of Denmark, DTU Physics Building 309, DK-2800 Kongens Lyngby, Denmark
| | - Per Augustsson
- Department of Biomedical Engineering, Lund University, Ole Römers väg 3, 22363 Lund, Sweden
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23
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Goering C, Dual J. Dynamic measurement of the acoustic streaming time constant utilizing an optical tweezer. Phys Rev E 2021; 104:025104. [PMID: 34525602 DOI: 10.1103/physreve.104.025104] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 07/22/2021] [Indexed: 06/13/2023]
Abstract
The combination of a bulk acoustic wave device and an optical trap allows for studying the buildup time of the respective acoustic forces. In particular, we are interested in the time it takes to build up the acoustic radiation force and acoustic streaming. For that, we measure the trajectory of a spherical particle in an acoustic field over time. The shape of the trajectory is determined by the acoustic radiation force and by acoustic streaming, both acting on different time scales. For that, we utilize the high temporal resolution (Δt=0.8μs) of an optical trapping setup. With our experimental parameters the acoustic radiation force on the particle and the acoustic streaming field theoretically have characteristic buildup times of 1.4μs and 1.44ms, respectively. By choosing a resonance mode and a measurement position where the acoustic radiation force and acoustic streaming induced viscous drag force act in orthogonal directions, we can measure the evolution of these effects separately. Our results show that the particle is accelerated nearly instantaneously by the acoustic radiation force to a constant velocity, whereas the acceleration phase to a constant velocity by the acoustic streaming field takes significantly longer. We find that the acceleration to a constant velocity induced by streaming takes in average about 17 500 excitation periods (≈4.4ms) longer to develop than the one induced by the acoustic radiation force. This duration is about four times larger than the so-called momentum diffusion time which is used to estimate the streaming buildup. In addition, this rather large difference in time can explain why a pulsed acoustic excitation can indeed prevent acoustic streaming as it has been shown in some previous experiments.
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Affiliation(s)
- Christoph Goering
- ETH Zurich, Institute for Mechanical Systems, Leonhardstr. 21, 8092 Zurich, Switzerland
| | - Jürg Dual
- ETH Zurich, Institute for Mechanical Systems, Leonhardstr. 21, 8092 Zurich, Switzerland
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24
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Winckelmann BG, Bruus H. Theory and simulation of electroosmotic suppression of acoustic streaming. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 149:3917. [PMID: 34241445 DOI: 10.1121/10.0005051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 04/29/2021] [Indexed: 06/13/2023]
Abstract
Acoustic handling of nanoparticles in resonating acoustofluidic devices is often impeded by the presence of acoustic streaming. For micrometer-sized acoustic chambers, this acoustic streaming is typically driven by viscous shear in the thin acoustic boundary layer near the fluid-solid interface. Alternating current (ac) electroosmosis is another boundary-driven streaming phenomenon routinely used in microfluidic devices for the handling of particle suspensions in electrolytes. Here, we study how streaming can be suppressed by combining ultrasound acoustics and ac electroosmosis. Based on a theoretical analysis of the electrokinetic problem, we are able to compute numerically a form of the electrical potential at the fluid-solid interface, which is suitable for suppressing the typical acoustic streaming pattern associated with a standing acoustic half-wave. In the linear regime, we even derive an analytical expression for the electroosmotic slip velocity at the fluid-solid interface and use this as a guiding principle for developing models in the experimentally more relevant nonlinear regime that occurs at elevated driving voltages. We present simulation results for an acoustofluidic device, showing how implementing a suitable ac electroosmosis results in a suppression of the resulting electroacoustic streaming in the bulk of the device by 2 orders of magnitude.
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Affiliation(s)
- Bjørn G Winckelmann
- Department of Physics, Technical University of Denmark, DTU Physics Building 309, DK-2800 Kongens Lyngby, Denmark
| | - Henrik Bruus
- Department of Physics, Technical University of Denmark, DTU Physics Building 309, DK-2800 Kongens Lyngby, Denmark
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Freitag S, Baumgartner B, Radel S, Schwaighofer A, Varriale A, Pennacchio A, D'Auria S, Lendl B. A thermoelectrically stabilized aluminium acoustic trap combined with attenuated total reflection infrared spectroscopy for detection of Escherichia coli in water. LAB ON A CHIP 2021; 21:1811-1819. [PMID: 33949396 DOI: 10.1039/d0lc01264e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Acoustic trapping is a non-contact particle manipulation method that holds great potential for performing automated assays. We demonstrate an aluminium acoustic trap in combination with attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) for detection of E. coli in water. The thermal conductivity of aluminium was exploited to thermo-electrically heat and hold the acoustic trap at the desired assay temperature of 37 °C. Systematic characterisation and optimisation of the acoustic trap allowed high flow rates while maintaining high acoustic trapping performance. The ATR element serves not only as a reflector for ultrasound standing wave generation but also as a sensing interface. The enzyme conversion induced by alkaline phosphatase-labelled bacteria was directly monitored in the acoustic trap using ATR-FTIR spectroscopy. Sequential injection analysis allowed automated liquid handling, including non-contact bacteria retention, washing and enzyme-substrate exchange within the acoustic trap. The presented method was able to detect E. coli concentrations as low as 1.95 × 106 bacteria per mL in 197 min. The demonstrated ultrasound assisted assay paves the way to fully automated bacteria detection devices based on acoustic trapping combined with ATR-FTIR spectroscopy.
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Affiliation(s)
- Stephan Freitag
- Research Division of Environmental Analytics, Process Analytics and Sensors, Institute of Chemical Technologies and Analytics, Technische Universität Wien, Getreidemarkt 9/164-UPA, 1060 Vienna, Austria.
| | - Bettina Baumgartner
- Research Division of Environmental Analytics, Process Analytics and Sensors, Institute of Chemical Technologies and Analytics, Technische Universität Wien, Getreidemarkt 9/164-UPA, 1060 Vienna, Austria.
| | - Stefan Radel
- Research Division of Environmental Analytics, Process Analytics and Sensors, Institute of Chemical Technologies and Analytics, Technische Universität Wien, Getreidemarkt 9/164-UPA, 1060 Vienna, Austria.
| | - Andreas Schwaighofer
- Research Division of Environmental Analytics, Process Analytics and Sensors, Institute of Chemical Technologies and Analytics, Technische Universität Wien, Getreidemarkt 9/164-UPA, 1060 Vienna, Austria.
| | - Antonio Varriale
- Institute of Food Science, CNR, Via Roma 64, 83100 Avellino, Italy
| | | | - Sabato D'Auria
- Institute of Food Science, CNR, Via Roma 64, 83100 Avellino, Italy
| | - Bernhard Lendl
- Research Division of Environmental Analytics, Process Analytics and Sensors, Institute of Chemical Technologies and Analytics, Technische Universität Wien, Getreidemarkt 9/164-UPA, 1060 Vienna, Austria.
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Joergensen JH, Bruus H. Theory of pressure acoustics with thermoviscous boundary layers and streaming in elastic cavities. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 149:3599. [PMID: 34241087 DOI: 10.1121/10.0005005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 04/23/2021] [Indexed: 06/13/2023]
Abstract
We present an effective thermoviscous theory of acoustofluidics including pressure acoustics, thermoviscous boundary layers, and streaming for fluids embedded in elastic cavities. By including thermal fields, we thus extend the effective viscous theory by Bach and Bruus [J. Acoust. Soc. Am. 144, 766 (2018)]. The acoustic temperature field and the thermoviscous boundary layers are incorporated analytically as effective boundary conditions and time-averaged body forces on the thermoacoustic bulk fields. Because it avoids resolving the thin boundary layers, the effective model allows for numerical simulation of both thermoviscous acoustic and time-averaged fields in three-dimensional models of acoustofluidic systems. We show how the acoustic streaming depends strongly on steady and oscillating thermal fields through the temperature dependency of the material parameters, in particular the viscosity and the compressibility, affecting both the boundary conditions and spawning additional body forces in the bulk. We also show how even small steady temperature gradients ( ∼1 K/mm) induce gradients in compressibility and density that may result in very high streaming velocities ( ∼1 mm/s) for moderate acoustic energy densities ( ∼100 J/m3).
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Affiliation(s)
- Jonas Helboe Joergensen
- Department of Physics, Technical University of Denmark, DTU Physics Building 309, DK-2800 Kongens Lyngby, Denmark
| | - Henrik Bruus
- Department of Physics, Technical University of Denmark, DTU Physics Building 309, DK-2800 Kongens Lyngby, Denmark
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Chen C, Gu Y, Philippe J, Zhang P, Bachman H, Zhang J, Mai J, Rufo J, Rawls JF, Davis EE, Katsanis N, Huang TJ. Acoustofluidic rotational tweezing enables high-speed contactless morphological phenotyping of zebrafish larvae. Nat Commun 2021; 12:1118. [PMID: 33602914 PMCID: PMC7892888 DOI: 10.1038/s41467-021-21373-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 01/08/2021] [Indexed: 01/31/2023] Open
Abstract
Modern biomedical research and preclinical pharmaceutical development rely heavily on the phenotyping of small vertebrate models for various diseases prior to human testing. In this article, we demonstrate an acoustofluidic rotational tweezing platform that enables contactless, high-speed, 3D multispectral imaging and digital reconstruction of zebrafish larvae for quantitative phenotypic analysis. The acoustic-induced polarized vortex streaming achieves contactless and rapid (~1 s/rotation) rotation of zebrafish larvae. This enables multispectral imaging of the zebrafish body and internal organs from different viewing perspectives. Moreover, we develop a 3D reconstruction pipeline that yields accurate 3D models based on the multi-view images for quantitative evaluation of basic morphological characteristics and advanced combinations of metrics. With its contactless nature and advantages in speed and automation, our acoustofluidic rotational tweezing system has the potential to be a valuable asset in numerous fields, especially for developmental biology, small molecule screening in biochemistry, and pre-clinical drug development in pharmacology.
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Affiliation(s)
- Chuyi Chen
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC, USA
| | - Yuyang Gu
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC, USA
| | - Julien Philippe
- Center for Human Disease Modeling, Duke University Medical Center, Durham, NC, USA
| | - Peiran Zhang
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC, USA
| | - Hunter Bachman
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC, USA
| | - Jinxin Zhang
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC, USA
| | - John Mai
- Alfred E. Mann Institute for Biomedical Engineering, University of Southern California, Los Angeles, CA, USA
| | - Joseph Rufo
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC, USA
| | - John F Rawls
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA
| | - Erica E Davis
- Center for Human Disease Modeling, Duke University Medical Center, Durham, NC, USA
- Advanced Center for Translational and Genetic Medicine (ACT-GeM), Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
- Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Nicholas Katsanis
- Center for Human Disease Modeling, Duke University Medical Center, Durham, NC, USA
- Advanced Center for Translational and Genetic Medicine (ACT-GeM), Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
- Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Tony Jun Huang
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC, USA.
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Aghakhani A, Cetin H, Erkoc P, Tombak GI, Sitti M. Flexural wave-based soft attractor walls for trapping microparticles and cells. LAB ON A CHIP 2021; 21:582-596. [PMID: 33355319 PMCID: PMC7612665 DOI: 10.1039/d0lc00865f] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Acoustic manipulation of microparticles and cells, called acoustophoresis, inside microfluidic systems has significant potential in biomedical applications. In particular, using acoustic radiation force to push microscopic objects toward the wall surfaces has an important role in enhancing immunoassays, particle sensors, and recently microrobotics. In this paper, we report a flexural-wave based acoustofluidic system for trapping micron-sized particles and cells at the soft wall boundaries. By exciting a standard microscope glass slide (1 mm thick) at its resonance frequencies <200 kHz, we show the wall-trapping action in sub-millimeter-size rectangular and circular cross-sectional channels. For such low-frequency excitation, the acoustic wavelength can range from 10-150 times the microchannel width, enabling a wide design space for choosing the channel width and position on the substrate. Using the system-level acousto-structural simulations, we confirm the acoustophoretic motion of particles near the walls, which is governed by the competing acoustic radiation and streaming forces. Finally, we investigate the performance of the wall-trapping acoustofluidic setup in attracting the motile cells, such as Chlamydomonas reinhardtii microalgae, toward the soft boundaries. Furthermore, the rotation of microalgae at the sidewalls and trap-escape events under pulsed ultrasound are demonstrated. The flexural-wave driven acoustofluidic system described here provides a biocompatible, versatile, and label-free approach to attract particles and cells toward the soft walls.
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Affiliation(s)
- Amirreza Aghakhani
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany.
| | - Hakan Cetin
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany. and Electrical and Electronics Engineering Department, Özyeğin University, 34794 Istanbul, Turkey
| | - Pelin Erkoc
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany. and Faculty of Engineering and Natural Sciences, Bahcesehir University, 34353 Istanbul, Turkey
| | - Guney Isik Tombak
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany. and Electrical and Electronics Engineering Department, Boğaziçi University, 34342 Istanbul, Turkey
| | - Metin Sitti
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany. and Institute for Biomedical Engineering, ETH Zurich, 8092 Zurich, Switzerland and School of Medicine and School of Engineering, Koç University, 34450 Istanbul, Turkey
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Gu Y, Chen C, Mao Z, Bachman H, Becker R, Rufo J, Wang Z, Zhang P, Mai J, Yang S, Zhang J, Zhao S, Ouyang Y, Wong DTW, Sadovsky Y, Huang TJ. Acoustofluidic centrifuge for nanoparticle enrichment and separation. SCIENCE ADVANCES 2021; 7:eabc0467. [PMID: 33523836 PMCID: PMC7775782 DOI: 10.1126/sciadv.abc0467] [Citation(s) in RCA: 90] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 11/05/2020] [Indexed: 05/19/2023]
Abstract
Liquid droplets have been studied for decades and have recently experienced renewed attention as a simplified model for numerous fascinating physical phenomena occurring on size scales from the cell nucleus to stellar black holes. Here, we present an acoustofluidic centrifugation technique that leverages an entanglement of acoustic wave actuation and the spin of a fluidic droplet to enable nanoparticle enrichment and separation. By combining acoustic streaming and droplet spinning, rapid (<1 min) nanoparticle concentration and size-based separation are achieved with a resolution sufficient to identify and isolate exosome subpopulations. The underlying physical mechanisms have been characterized both numerically and experimentally, and the ability to process biological samples (including DNA segments and exosome subpopulations) has been successfully demonstrated. Together, this acoustofluidic centrifuge overcomes existing limitations in the manipulation of nanoscale (<100 nm) bioparticles and can be valuable for various applications in the fields of biology, chemistry, engineering, material science, and medicine.
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Affiliation(s)
- Yuyang Gu
- Department of Mechanical Engineering and Materials Science, Duke University, NC 27708, USA
| | - Chuyi Chen
- Department of Mechanical Engineering and Materials Science, Duke University, NC 27708, USA
| | - Zhangming Mao
- Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA 16801, USA
| | - Hunter Bachman
- Department of Mechanical Engineering and Materials Science, Duke University, NC 27708, USA
| | - Ryan Becker
- Department of Biomedical Engineering, Duke University, NC 27708, USA
| | - Joseph Rufo
- Department of Mechanical Engineering and Materials Science, Duke University, NC 27708, USA
| | - Zeyu Wang
- Department of Mechanical Engineering and Materials Science, Duke University, NC 27708, USA
| | - Peiran Zhang
- Department of Mechanical Engineering and Materials Science, Duke University, NC 27708, USA
| | - John Mai
- Alfred E. Mann Institute for Biomedical Engineering, University of Southern California, Los Angeles, CA 90089, USA
| | - Shujie Yang
- Department of Mechanical Engineering and Materials Science, Duke University, NC 27708, USA
| | - Jinxin Zhang
- Department of Mechanical Engineering and Materials Science, Duke University, NC 27708, USA
| | - Shuaiguo Zhao
- Department of Mechanical Engineering and Materials Science, Duke University, NC 27708, USA
| | - Yingshi Ouyang
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Magee-Womens Research Institute, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - David T W Wong
- School of Dentistry and the Departments of Otolaryngology/Head and Neck Surgery and Pathology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Yoel Sadovsky
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Magee-Womens Research Institute, University of Pittsburgh, Pittsburgh, PA 15213, USA
- School of Medicine, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Tony Jun Huang
- Department of Mechanical Engineering and Materials Science, Duke University, NC 27708, USA.
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30
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Hao N, Pei Z, Liu P, Bachman H, Naquin TD, Zhang P, Zhang J, Shen L, Yang S, Yang K, Zhao S, Huang TJ. Acoustofluidics-Assisted Fluorescence-SERS Bimodal Biosensors. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2005179. [PMID: 33174375 PMCID: PMC7902458 DOI: 10.1002/smll.202005179] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 09/29/2020] [Indexed: 05/23/2023]
Abstract
Acoustofluidics, the fusion of acoustics and microfluidic techniques, has recently seen increased research attention across multiple disciplines due in part to its capabilities in contactless, biocompatible, and precise manipulation of micro-/nano-objects. Herein, a bimodal signal amplification platform which relies on acoustofluidics-induced enrichment of nanoparticles is introduced. The dual-function biosensor can perform sensitive immunofluorescent or surface-enhanced Raman spectroscopy (SERS) detection. The platform functions by using surface acoustic waves to concentrate nanoparticles at either the center or perimeter of a glass capillary; the concentration location is adjusted simply by varying the input frequency. The immunofluorescence assay is achieved by concentrating fluorescent analytes and functionalized nanoparticles at the center of the microchannel, thereby improving the visibility of the fluorescent output. By modifying the inner wall of the glass capillary with plasmonic Ag nanoparticle-deposited ZnO nanorod arrays and focusing analytes toward the perimeter of the microchannel, SERS sensing using the same device setup is achieved. Nanosized exosomes are used as a proof-of-concept to validate the performance of the acoustofluidic bimodal biosensor. With its sample-enrichment functionality, bimodal sensing, short processing time, and minute sample consumption, the acoustofluidic chip holds great potential for the development of lab-on-a-chip based analysis systems in many real-world applications.
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Affiliation(s)
- Nanjing Hao
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708, USA
| | - Zhichao Pei
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708, USA
| | - Pengzhan Liu
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708, USA
| | - Hunter Bachman
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708, USA
| | - Ty Downing Naquin
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708, USA
| | - Peiran Zhang
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708, USA
| | - Jinxin Zhang
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708, USA
| | - Liang Shen
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708, USA
| | - Shujie Yang
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708, USA
| | - Kaichun Yang
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708, USA
| | - Shuaiguo Zhao
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708, USA
| | - Tony Jun Huang
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708, USA
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31
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Spigarelli L, Vasile NS, Pirri CF, Canavese G. Numerical study of the effect of channel aspect ratio on particle focusing in acoustophoretic devices. Sci Rep 2020; 10:19447. [PMID: 33173108 PMCID: PMC7655847 DOI: 10.1038/s41598-020-76367-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 10/27/2020] [Indexed: 11/18/2022] Open
Abstract
Acoustophoretic microfluidic devices are promising non-contact and high-throughput tools for particle manipulation. Although the effectiveness of this technique has been widely demonstrated for applications based on micrometer-sized particles, the manipulation and focusing of sub-micrometer ones is challenging due to the presence of acoustic streaming. In this article, our study has the aim to investigate and understand which geometrical parameters could be changed to limit the acoustic streaming effect. We numerically study the well-known rectangular cross section of a microfluidic channel and perform a parametric study of the aspect ratio for several particle sizes. The efficiency of the focusing, is explored for different sized particles in order to identify a trend for which the acoustic streaming does not drastically influence the focusing motion of the particles. The possibility to efficiently separate different solid components in liquid suspensions, i.e. the whole blood, is crucial for all applications that require a purified medium such as plasmapheresis or an increase of the concentration of specific subpopulation as the outcome, such as proteomics, cancer biomarker detections and extracellular vesicles separation.
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Affiliation(s)
- L Spigarelli
- Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Turin, Italy.
| | - N S Vasile
- SynBio Lab, Italian Institute of Technology, Via Livorno 60, 10144, Turin, Italy
| | - C F Pirri
- Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Turin, Italy.,Chilab - Materials and Microsystems Laboratory - DISAT Politecnico di Torino, Via Lungo Piazza d'Armi 6, 10034, Chivasso (Turin), Italy
| | - G Canavese
- Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Turin, Italy. .,Chilab - Materials and Microsystems Laboratory - DISAT Politecnico di Torino, Via Lungo Piazza d'Armi 6, 10034, Chivasso (Turin), Italy.
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Gerlt MS, Haidas D, Ratschat A, Suter P, Dittrich PS, Dual J. Manipulation of single cells inside nanoliter water droplets using acoustic forces. BIOMICROFLUIDICS 2020; 14:064112. [PMID: 33381252 PMCID: PMC7749759 DOI: 10.1063/5.0036407] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 12/08/2020] [Indexed: 05/10/2023]
Abstract
Droplet microfluidics enables high-throughput screening of single cells and is particularly valuable for applications, where the secreted compounds are analyzed. Typically, optical methods are employed for analysis, which are limited in their applicability as labeling protocols are required. Alternative label-free methods such as mass spectrometry would broaden the range of assays but are harmful to the cells, which is detrimental for some applications such as directed evolution. In this context, separation of cells from supernatant is beneficial prior to the analysis to retain viable cells. In this work, we propose an in-droplet separation method based on contactless and label-free acoustic particle manipulation. In a microfluidic chip, nanoliter droplets containing particles are produced at a T-junction. The particles are trapped in the tip of the droplet by the interplay of acoustic forces in two dimensions and internal flow fields. The droplets are subsequently split at a second T-junction into two daughter droplets-one containing the supernatant and the other containing the corresponding particles. The separation efficiency is measured in detail for polystyrene (PS) beads as a function of droplet speed, size, split ratio, and particle concentration. Further, single-bead (PS) and single-cell (yeast) experiments were carried out. At a throughput of 114 droplets/min, a separation efficiency of 100% ± 0% was achieved for more than 150 droplets. Finally, mammalian cells and bacteria were introduced into the system to test its versatility. This work demonstrates a robust, non-invasive strategy to perform single yeast cell-supernatant sampling in nanoliter volumes.
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Affiliation(s)
- Michael S. Gerlt
- Department of Mechanical and Process Engineering, ETH Zurich, Institute for Mechanical Systems (IMES), Tannenstrasse 3, CH-8092 Zurich, Switzerland
| | - Dominik Haidas
- Department of Biosystems Science and Engineering, ETH Zurich, Bioanalytics Group, Mattenstrasse 26, CH-4058 Basel, Switzerland
| | - Alexandre Ratschat
- Department of Mechanical and Process Engineering, ETH Zurich, Institute for Mechanical Systems (IMES), Tannenstrasse 3, CH-8092 Zurich, Switzerland
| | - Philipp Suter
- Department of Mechanical and Process Engineering, ETH Zurich, Institute for Mechanical Systems (IMES), Tannenstrasse 3, CH-8092 Zurich, Switzerland
| | - Petra S. Dittrich
- Department of Biosystems Science and Engineering, ETH Zurich, Bioanalytics Group, Mattenstrasse 26, CH-4058 Basel, Switzerland
| | - Jürg Dual
- Department of Mechanical and Process Engineering, ETH Zurich, Institute for Mechanical Systems (IMES), Tannenstrasse 3, CH-8092 Zurich, Switzerland
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Acoustic Microfluidic Separation Techniques and Bioapplications: A Review. MICROMACHINES 2020; 11:mi11100921. [PMID: 33023173 PMCID: PMC7600273 DOI: 10.3390/mi11100921] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 09/25/2020] [Accepted: 09/29/2020] [Indexed: 12/12/2022]
Abstract
Microfluidic separation technology has garnered significant attention over the past decade where particles are being separated at a micro/nanoscale in a rapid, low-cost, and simple manner. Amongst a myriad of separation technologies that have emerged thus far, acoustic microfluidic separation techniques are extremely apt to applications involving biological samples attributed to various advantages, including high controllability, biocompatibility, and non-invasive, label-free features. With that being said, downsides such as low throughput and dependence on external equipment still impede successful commercialization from laboratory-based prototypes. Here, we present a comprehensive review of recent advances in acoustic microfluidic separation techniques, along with exemplary applications. Specifically, an inclusive overview of fundamental theory and background is presented, then two sets of mechanisms underlying acoustic separation, bulk acoustic wave and surface acoustic wave, are introduced and discussed. Upon these summaries, we present a variety of applications based on acoustic separation. The primary focus is given to those associated with biological samples such as blood cells, cancer cells, proteins, bacteria, viruses, and DNA/RNA. Finally, we highlight the benefits and challenges behind burgeoning developments in the field and discuss the future perspectives and an outlook towards robust, integrated, and commercialized devices based on acoustic microfluidic separation.
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Devendran C, Choi K, Han J, Ai Y, Neild A, Collins DJ. Diffraction-based acoustic manipulation in microchannels enables continuous particle and bacteria focusing. LAB ON A CHIP 2020; 20:2674-2688. [PMID: 32608464 DOI: 10.1039/d0lc00397b] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Acoustic fields have shown wide utility for micromanipulation, though their implementation in microfluidic devices often requires accurate alignment or highly precise channel dimensions, including in typical standing surface acoustic wave (SSAW) devices and resonant channels. In this work we investigate an approach that permits continuous microscale focusing based on diffractive acoustics, a phenomenon where a time-averaged spatially varying acoustic pressure landscape is produced by bounding a surface acoustic wave (SAW) transducer with a microchannel. By virtue of diffractive effects, this acoustic field is formed with the application of only a single travelling wave. As the field is dictated by the interplay between a propagating substrate-bound wave and a channel geometry, the pressure distribution will be identical for a given channel orientation regardless of its translation on a SAW substrate, and where small variations in channel size have no substantive effect on the pressure field magnitude or overall particle migration. Moreover, in the case of a channel with dimensions on the order of the diffractive fringe pattern spacing, the number of focusing positions will be identical for all channel orientations, with acoustic radiation forces pushing suspended particles to the channel edges. We explore this highly robust particle manipulation technique, determining two distinct sets of streaming and acoustic radiation dominant concentration positions, and show the continuous focusing of polystyrene 1 μm and 0.5 μm diameter particles and fluorescently labeled E. coli bacteria cells at flow rates exceeding those of previous microfluidic implementations for micron and submicron sized particles.
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Affiliation(s)
- Citsabehsan Devendran
- Dept. Mechanical and Aerospace Engineering, Monash University, Clayton 3800, Australia
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Tahmasebipour A, Friedrich L, Begley M, Bruus H, Meinhart C. Toward optimal acoustophoretic microparticle manipulation by exploiting asymmetry. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2020; 148:359. [PMID: 32752779 DOI: 10.1121/10.0001634] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 07/09/2020] [Indexed: 06/11/2023]
Abstract
The performance of a micro-acousto-fluidic device designed for microparticle trapping is simulated using a three-dimensional (3D) numerical model. It is demonstrated by numerical simulations that geometrically asymmetric architecture and actuation can increase the acoustic radiation forces in a liquid-filled cavity by almost 2 orders of magnitude when setting up a standing pressure half wave in a microfluidic chamber. Similarly, experiments with silicon-glass devices show a noticeable improvement in acoustophoresis of 20-μm silica beads in water when asymmetric devices are used. Microparticle acoustophoresis has an extensive array of applications in applied science fields ranging from life sciences to 3D printing. A more efficient and powerful particle manipulation system can boost the overall effectiveness of an acoustofluidic device. The numerical simulations are developed in the COMSOL Multiphysics® software package (COMSOL AB, Stockholm, Sweden). By monitoring the modes and magnitudes of simulated acoustophoretic fields in a relatively wide range of ultrasonic frequencies, a map of device performance is obtained. 3D resonant acoustophoretic fields are identified to quantify the improved performance of the chips with an asymmetric layout. Four different device designs are analyzed experimentally, and particle tracking experimental data qualitatively supports the numerical results.
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Affiliation(s)
- Amir Tahmasebipour
- Department of Mechanical Engineering, University of California Santa Barbara, Santa Barbara, California 93106, USA
| | - Leanne Friedrich
- Materials Department, University of California Santa Barbara, Santa Barbara, California 93106, USA
| | - Matthew Begley
- Department of Mechanical Engineering, University of California Santa Barbara, Santa Barbara, California 93106, USA
| | - Henrik Bruus
- Department of Physics, Technical University of Denmark, Danmarks Tekniske Universitet Physics Building 309, 2800 Kongens Lyngby, Denmark
| | - Carl Meinhart
- Department of Mechanical Engineering, University of California Santa Barbara, Santa Barbara, California 93106, USA
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36
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Qiu W, Bruus H, Augustsson P. Particle-size-dependent acoustophoretic motion and depletion of micro- and nano-particles at long timescales. Phys Rev E 2020; 102:013108. [PMID: 32794927 DOI: 10.1103/physreve.102.013108] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 07/01/2020] [Indexed: 06/11/2023]
Abstract
We present three-dimensional measurements of particle-size-dependent acoustophoretic motion of microparticles with diameters from 4.8 μm down to 0.5 μm suspended in either homogeneous or inhomogeneous fluids inside a glass-silicon microchannel and exposed to a standing ultrasound wave. To study the crossover from radiation force dominated to streaming dominated motion as the particle size is decreased, we extend previous studies to long timescales, where the particles smaller than the crossover size move over distances comparable to the channel width. We observe a particle-size-dependent particle depletion at late times for the particles smaller than the crossover size. The mechanisms behind this depletion in homogeneous fluids are rationalized by numerical simulations which take the Brownian motion into account. Experimentally, the particle trajectories in inhomogeneous fluids show focusing in the bulk of the microchannel at early times, even for the particles below the critical size, which clearly demonstrates the potential to manipulate submicrometer particles.
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Affiliation(s)
- Wei Qiu
- Department of Physics, Technical University of Denmark, DTU Physics Building 309, DK-2800 Kongens Lyngby, Denmark
- Department of Biomedical Engineering, Lund University, Ole Römers väg 3, 22363, Lund, Sweden
| | - Henrik Bruus
- Department of Physics, Technical University of Denmark, DTU Physics Building 309, DK-2800 Kongens Lyngby, Denmark
| | - Per Augustsson
- Department of Biomedical Engineering, Lund University, Ole Römers väg 3, 22363, Lund, Sweden
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37
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Olm F, Lim HC, Schallmoser K, Strunk D, Laurell T, Scheding S. Acoustophoresis Enables the Label‐Free Separation of Functionally Different Subsets of Cultured Bone Marrow Stromal Cells. Cytometry A 2020; 99:476-487. [DOI: 10.1002/cyto.a.24171] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 06/06/2020] [Accepted: 06/11/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Franziska Olm
- Department of Laboratory Medicine, Lund Stem Cell Center and Molecular Hematology Lund University Lund Sweden
| | - Hooi Ching Lim
- Department of Laboratory Medicine, Lund Stem Cell Center and Molecular Hematology Lund University Lund Sweden
| | - Katharina Schallmoser
- Department of Transfusion Medicine, Spinal Cord Injury and Tissue Regeneration Center Paracelsus Medical University Salzburg Austria
| | - Dirk Strunk
- Department of Experimental and Clinical Cell Therapy, Spinal Cord Injury and Tissue Regeneration Center Paracelsus Medical University Salzburg Austria
| | - Thomas Laurell
- Department of Biomedical Engineering Lund University Lund Sweden
| | - Stefan Scheding
- Department of Laboratory Medicine, Lund Stem Cell Center and Molecular Hematology Lund University Lund Sweden
- Department of Haematology Skåne University Hospital Lund Sweden
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38
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Tayebi M, O'Rorke R, Wong HC, Low HY, Han J, Collins DJ, Ai Y. Massively Multiplexed Submicron Particle Patterning in Acoustically Driven Oscillating Nanocavities. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2000462. [PMID: 32196142 DOI: 10.1002/smll.202000462] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 02/24/2020] [Indexed: 06/10/2023]
Abstract
Nanoacoustic fields are a promising method for particle actuation at the nanoscale, though THz frequencies are typically required to create nanoscale wavelengths. In this work, the generation of robust nanoscale force gradients is demonstrated using MHz driving frequencies via acoustic-structure interactions. A structured elastic layer at the interface between a microfluidic channel and a traveling surface acoustic wave (SAW) device results in submicron acoustic traps, each of which can trap individual submicron particles. The acoustically driven deformation of nanocavities gives rise to time-averaged acoustic fields which direct suspended particles toward, and trap them within, the nanocavities. The use of SAWs permits massively multiplexed particle manipulation with deterministic patterning at the single-particle level. In this work, 300 nm diameter particles are acoustically trapped in 500 nm diameter cavities using traveling SAWs with wavelengths in the range of 20-80 µm with one particle per cavity. On-demand generation of nanoscale acoustic force gradients has wide applications in nanoparticle manipulation, including bioparticle enrichment and enhanced catalytic reactions for industrial applications.
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Affiliation(s)
- Mahnoush Tayebi
- Pillar of Engineering Product Development, Singapore University of Technology and Design, Singapore, 487372, Singapore
| | - Richard O'Rorke
- Pillar of Engineering Product Development, Singapore University of Technology and Design, Singapore, 487372, Singapore
| | - Him Cheng Wong
- Pillar of Engineering Product Development, Singapore University of Technology and Design, Singapore, 487372, Singapore
| | - Hong Yee Low
- Pillar of Engineering Product Development, Singapore University of Technology and Design, Singapore, 487372, Singapore
| | - Jongyoon Han
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - David J Collins
- Department of Biomedical Engineering, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Ye Ai
- Pillar of Engineering Product Development, Singapore University of Technology and Design, Singapore, 487372, Singapore
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39
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Van Assche D, Reithuber E, Qiu W, Laurell T, Henriques-Normark B, Mellroth P, Ohlsson P, Augustsson P. Gradient acoustic focusing of sub-micron particles for separation of bacteria from blood lysate. Sci Rep 2020; 10:3670. [PMID: 32111864 PMCID: PMC7048738 DOI: 10.1038/s41598-020-60338-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 02/11/2020] [Indexed: 02/08/2023] Open
Abstract
Handling of submicron-sized objects is important in many biochemical and biomedical applications, but few methods today can precisely manipulate this range of particles. We present gradient acoustic focusing that enables flow-through particle separation of submicron particles and cells and we apply it for separation of bacteria from blood lysate to facilitate their detection in whole blood for improved diagnostics. To control suspended objects below the classical 2µm size limit for acoustic focusing, we introduce a co-flowing acoustic impedance gradient to generate a stabilizing acoustic volume force that supresses acoustic streaming. The method is validated theoretically and experimentally using polystyrene particles, Staphylococcus aureus, Streptococcus pneumoniae and Escherichia coli. The applicability of the method is demonstrated by the separation of bacteria from selectively chemically lysed blood. Combined with downstream operations, this new approach opens up for novel methods for sepsis diagnostics.
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Affiliation(s)
- David Van Assche
- Department of Biomedical Engineering, Lund University, Ole Römers väg 3, 22363, Lund, Sweden.,CNRS, Univ. Bordeaux, CRPP, UMR 5031, 115 Avenue Schweitzer, 33600, Pessac, France
| | - Elisabeth Reithuber
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 77, Stockholm, Sweden
| | - Wei Qiu
- Department of Biomedical Engineering, Lund University, Ole Römers väg 3, 22363, Lund, Sweden
| | - Thomas Laurell
- Department of Biomedical Engineering, Lund University, Ole Römers väg 3, 22363, Lund, Sweden
| | - Birgitta Henriques-Normark
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 77, Stockholm, Sweden.,Department of Clinical Microbiology, Karolinska University Hospital, 17176, Stockholm, Sweden.,Singapore Centre for Environmental Life Sciences Engineering SCELSE and Le Kong Chian School of Medicine LKC, Nanyang Technological University, NTU, 50 Nanyang Ave, 639798, Nanyang, Singapore
| | - Peter Mellroth
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 77, Stockholm, Sweden
| | - Pelle Ohlsson
- Department of Biomedical Engineering, Lund University, Ole Römers väg 3, 22363, Lund, Sweden.
| | - Per Augustsson
- Department of Biomedical Engineering, Lund University, Ole Römers väg 3, 22363, Lund, Sweden.
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40
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Numerical Simulation of Boundary-Driven Acoustic Streaming in Microfluidic Channels with Circular Cross-Sections. MICROMACHINES 2020; 11:mi11030240. [PMID: 32111024 PMCID: PMC7143890 DOI: 10.3390/mi11030240] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 02/06/2020] [Accepted: 02/10/2020] [Indexed: 01/08/2023]
Abstract
While acoustic streaming patterns in microfluidic channels with rectangular cross-sections have been widely shown in the literature, boundary-driven streaming fields in non-rectangular channels have not been well studied. In this paper, a two-dimensional numerical model was developed to simulate the boundary-driven streaming fields on cross-sections of cylindrical fluid channels. Firstly, the linear acoustic pressure fields at the resonant frequencies were solved from the Helmholtz equation. Subsequently, the outer boundary-driven streaming fields in the bulk of fluid were modelled while using Nyborg’s limiting velocity method, of which the limiting velocity equations were extended to be applicable for cylindrical surfaces in this work. In particular, acoustic streaming fields in the primary (1, 0) mode were presented. The results are expected to be valuable to the study of basic physical aspects of microparticle acoustophoresis in microfluidic channels with circular cross-sections and the design of acoustofluidic devices for micromanipulation.
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41
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Zhang T, Hong ZY, Tang SY, Li W, Inglis DW, Hosokawa Y, Yalikun Y, Li M. Focusing of sub-micrometer particles in microfluidic devices. LAB ON A CHIP 2020; 20:35-53. [PMID: 31720655 DOI: 10.1039/c9lc00785g] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Sub-micrometer particles (0.10-1.0 μm) are of great significance to study, e.g., microvesicles and protein aggregates are targets for therapeutic intervention, and sub-micrometer fluorescent polystyrene (PS) particles are used as probes for diagnostic imaging. Focusing of sub-micrometer particles - precisely control over the position of sub-micrometer particles in a tightly focused stream - has a wide range of applications in the field of biology, chemistry and environment, by acting as a prerequisite step for downstream detection, manipulation and quantification. Microfluidic devices have been attracting great attention as desirable tools for sub-micrometer particle focusing, due to their small size, low reagent consumption, fast analysis and low cost. Recent advancements in fundamental knowledge and fabrication technologies have enabled microfluidic focusing of particles at sub-micrometer scale in a continuous, label-free and high-throughput manner. Microfluidic methods for the focusing of sub-micrometer particles can be classified into two main groups depending on whether an external field is applied: 1) passive methods, which utilize intrinsic fluidic properties without the need of external actuation, such as inertial, deterministic lateral displacement (DLD), viscoelastic and hydrophoretic focusing; and 2) active methods, where external fields are used, such as dielectrophoretic, thermophoretic, acoustophoretic and optical focusing. This article mainly reviews the studies on the focusing of sub-micrometer particles in microfluidic devices over the past 10 years. It aims to bridge the gap between the focusing of micrometer and nanometer scale (1.0-100 nm) particles and to improve the understanding of development progress, current advances and future prospects in microfluidic focusing techniques.
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Affiliation(s)
- Tianlong Zhang
- Division of Materials Science, Nara Institute of Science and Technology, Nara 630-0192, Japan. and School of Engineering, Macquarie University, Sydney 2122, Australia.
| | - Zhen-Yi Hong
- Division of Materials Science, Nara Institute of Science and Technology, Nara 630-0192, Japan.
| | - Shi-Yang Tang
- School of Mechanical, Materials, Mechatronic and Biomedical Engineering, University of Wollongong, Wollongong 2522, Australia
| | - Weihua Li
- School of Mechanical, Materials, Mechatronic and Biomedical Engineering, University of Wollongong, Wollongong 2522, Australia
| | - David W Inglis
- School of Engineering, Macquarie University, Sydney 2122, Australia.
| | - Yoichiroh Hosokawa
- Division of Materials Science, Nara Institute of Science and Technology, Nara 630-0192, Japan.
| | - Yaxiaer Yalikun
- Division of Materials Science, Nara Institute of Science and Technology, Nara 630-0192, Japan.
| | - Ming Li
- School of Engineering, Macquarie University, Sydney 2122, Australia.
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42
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Collins DJ, O'Rorke R, Neild A, Han J, Ai Y. Acoustic fields and microfluidic patterning around embedded micro-structures subject to surface acoustic waves. SOFT MATTER 2019; 15:8691-8705. [PMID: 31657435 DOI: 10.1039/c9sm00946a] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Recent research has shown that interactions between acoustic waves and microfluidic channels can generate microscale interference patterns with the application of a traveling surface acoustic wave (SAW), effectively creating standing wave patterns with a traveling wave. Forces arising from this interference can be utilized for precise manipulation of micron-sized particles and biological cells. The patterns that have been produced with this method, however, have been limited to straight lines and grids from flat channel walls, and where the spacing resulting from this interference has not previously been comprehensively explored. In this work we examine the interaction between both straight and curved channel interfaces with a SAW to derive geometrically deduced analytical models. These models predict the acoustic force-field periodicity near a channel interface as a function of its orientation to an underlying SAW, and are validated with experimental and simulation results. Notably, the spacing is larger for flat walls than for curved ones and is dependent on the ratio of sound speeds in the substrate and fluid. Generating these force-field gradients with only travelling waves has wide applications in acoustofluidic systems, where channel interfaces can potentially support a range of patterning, concentration, focusing and separation activities by creating locally defined acoustic forces.
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Affiliation(s)
- David J Collins
- Department of Biomedical Engineering, The University of Melbourne, Melbourne, Victoria 3010, Australia.
| | - Richard O'Rorke
- Pillar of Engineering Product Development, Singapore University of Technology and Design, Singapore 487372, Singapore.
| | - Adrian Neild
- Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, VIC 3800, Australia
| | - Jongyoon Han
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA and Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ye Ai
- Pillar of Engineering Product Development, Singapore University of Technology and Design, Singapore 487372, Singapore.
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43
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Cheng CY, Dangi A, Ren L, Tiwari S, Benoit RR, Qiu Y, Lay HS, Agrawal S, Pratap R, Kothapalli SR, Mallouk TE, Cochran S, Trolier-Mckinstry S. Thin Film PZT-Based PMUT Arrays for Deterministic Particle Manipulation. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2019; 66:1606-1615. [PMID: 31283502 DOI: 10.1109/tuffc.2019.2926211] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Lead zirconate titanate (PZT)-based piezoelectric micromachined ultrasonic transducers (PMUTs) for particle manipulation applications were designed, fabricated, characterized, and tested. The PMUTs had a diaphragm diameter of 60 [Formula: see text], a resonant frequency of ~8 MHz, and an operational bandwidth (BW) of 62.5%. Acoustic pressure output in water was 9.5 kPa at 7.5 mm distance from a PMUT element excited with a unipolar waveform at 5 Vpp . The element consisted of 20 diaphragms connected electrically in parallel. Particle trapping of 4 [Formula: see text] silica beads was shown to be possible with 5 Vpp unipolar excitation. Trapping of multiple beads by a single element and deterministic control of particles via acoustophoresis without the assistance of microfluidic flow were demonstrated. It was found that the particles move toward diaphragm areas of highest pressure, in agreement with literature and simulations. Unique bead patterns were generated at different driving frequencies and were formed at frequencies up to 60 MHz, much higher than the operational BW. Levitation planes were generated above the 30 MHz driving frequency.
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44
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Sehgal P, Ramaswamy M, Cohen I, Kirby BJ. Using Acoustic Perturbations to Dynamically Tune Shear Thickening in Colloidal Suspensions. PHYSICAL REVIEW LETTERS 2019; 123:128001. [PMID: 31633960 DOI: 10.1103/physrevlett.123.128001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Indexed: 06/10/2023]
Abstract
Colloidal suspensions in industrial processes often exhibit shear thickening that is difficult to control actively. Here, we use piezoelectric transducers to apply acoustic perturbations to dynamically tune the suspension viscosity in the shear-thickening regime. We attribute the mechanism of dethickening to the disruption of shear-induced force chains via perturbations that are large relative to the particle roughness scale. The ease with which this technique can be adapted to various flow geometries makes it a powerful tool for actively controlling suspension flow properties and investigating system dynamics.
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Affiliation(s)
- Prateek Sehgal
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14853, USA
| | - Meera Ramaswamy
- Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - Itai Cohen
- Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - Brian J Kirby
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14853, USA
- Department of Medicine, Division of Hematology and Medical Oncology, Weill-Cornell Medicine, New York, New York 10021,USA
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45
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Habibi R, Neild A. Sound wave activated nano-sieve (SWANS) for enrichment of nanoparticles. LAB ON A CHIP 2019; 19:3032-3044. [PMID: 31396609 DOI: 10.1039/c9lc00369j] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Acoustic actuation is widely used in microfluidic systems as a method of controlling the behaviour of suspended matter. When acoustic waves impinge on particles, a radiation force is exerted which can cause migration over multiple acoustic time periods; in addition the scattering of the wave by the particle will affect the behaviour of nearby particles. This interparticle effect, or Bjerknes force, tends to attract particles together. Here, instead of manipulating a dilute sample of particles, we examine the acoustic excitation of a packed bed. We fill a microfluidic channel with microparticles, such that they form a closely packed structure and then excite them at the particle's resonant frequency. In this scenario, each particle acts as a source of scattered waves and we show that these waves are highly effective at attracting nanoparticles onto the surface of the microparticles, and nanoparticle collection characterises the performance of this mechanically activated packed bed.
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Affiliation(s)
- Ruhollah Habibi
- Laboratory for Micro Systems, Department of Mechanical and Aerospace Engineering, Monash University, Clayton, Victoria 3800, Australia.
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46
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Abstract
Cellular analysis is a central concept for both biology and medicine. Over the past two decades, acoustofluidic technologies, which marry acoustic waves with microfluidics, have significantly contributed to the development of innovative approaches for cellular analysis. Acoustofluidic technologies enable precise manipulations of cells and the fluids that confine them, and these capabilities have been utilized in many cell analysis applications. In this review article, we examine various applications where acoustofluidic methods have been implemented, including cell imaging, cell mechanotyping, circulating tumor cell phenotyping, sample preparation in clinics, and investigation of cell-cell interactions and cell-environment responses. We also provide our perspectives on the technological advantages, limitations, and potential future directions for this innovative field of methods.
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Affiliation(s)
- Yuliang Xie
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA
| | - Hunter Bachman
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC 27707, USA
| | - Tony Jun Huang
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC 27707, USA
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47
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Bach JS, Bruus H. Bulk-driven acoustic streaming at resonance in closed microcavities. Phys Rev E 2019; 100:023104. [PMID: 31574609 DOI: 10.1103/physreve.100.023104] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Indexed: 06/10/2023]
Abstract
Bulk-driven acoustic (Eckart) streaming is the steady flow resulting from the time-averaged acoustic energy flux density in the bulk of a viscous fluid. In simple cases, like the one-dimensional single standing-wave resonance, this energy flux is negligible, and therefore the bulk-driven streaming is often ignored relative to the boundary-driven (Rayleigh) streaming in the analysis of resonating acoustofluidic devices with length scales comparable to the acoustic wavelength. However, in closed acoustic microcavities with viscous dissipation, two overlapping resonances may be excited at the same frequency as a double mode. In contrast to single modes, the double modes can support a steady rotating acoustic energy flux density and thus a corresponding rotating bulk-driven acoustic streaming. We derive analytical solutions for the double modes in a rectangular-box-shaped cavity including the viscous boundary layers, and use them to map out possible rotating patterns of bulk-driven acoustic streaming. Remarkably, the rotating bulk-driven streaming may be excited by a nonrotating actuation, and we determine the optimal geometry that maximizes this excitation. In the optimal geometry, we finally simulate a horizontal 2×2, 4×4, and 6×6 streaming-roll pattern in a shallow square cavity. We find that the high-frequency 6×6 streaming-roll pattern is dominated by the bulk-driven streaming as opposed to the low-frequency 2×2 streaming pattern, which is dominated by the boundary-driven streaming.
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Affiliation(s)
- Jacob S Bach
- Department of Physics, Technical University of Denmark, DTU Physics Building 309, DK-2800 Kongens Lyngby, Denmark
| | - Henrik Bruus
- Department of Physics, Technical University of Denmark, DTU Physics Building 309, DK-2800 Kongens Lyngby, Denmark
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48
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Wu M, Ozcelik A, Rufo J, Wang Z, Fang R, Jun Huang T. Acoustofluidic separation of cells and particles. MICROSYSTEMS & NANOENGINEERING 2019; 5:32. [PMID: 31231539 PMCID: PMC6545324 DOI: 10.1038/s41378-019-0064-3] [Citation(s) in RCA: 178] [Impact Index Per Article: 35.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 03/12/2019] [Accepted: 03/14/2019] [Indexed: 05/03/2023]
Abstract
Acoustofluidics, the integration of acoustics and microfluidics, is a rapidly growing research field that is addressing challenges in biology, medicine, chemistry, engineering, and physics. In particular, acoustofluidic separation of biological targets from complex fluids has proven to be a powerful tool due to the label-free, biocompatible, and contact-free nature of the technology. By carefully designing and tuning the applied acoustic field, cells and other bioparticles can be isolated with high yield, purity, and biocompatibility. Recent advances in acoustofluidics, such as the development of automated, point-of-care devices for isolating sub-micron bioparticles, address many of the limitations of conventional separation tools. More importantly, advances in the research lab are quickly being adopted to solve clinical problems. In this review article, we discuss working principles of acoustofluidic separation, compare different approaches of acoustofluidic separation, and provide a synopsis of how it is being applied in both traditional applications, such as blood component separation, cell washing, and fluorescence activated cell sorting, as well as emerging applications, including circulating tumor cell and exosome isolation.
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Affiliation(s)
- Mengxi Wu
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC 27708 USA
| | - Adem Ozcelik
- Mechanical Engineering Department, Aydin Adnan Menderes University, 09010 Aydin, Turkey
| | - Joseph Rufo
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC 27708 USA
| | - Zeyu Wang
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC 27708 USA
| | - Rui Fang
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138 USA
| | - Tony Jun Huang
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC 27708 USA
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49
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Hemachandran E, Karthick S, Laurell T, Sen AK. Relocation of coflowing immiscible liquids under acoustic field in a microchannel. ACTA ACUST UNITED AC 2019. [DOI: 10.1209/0295-5075/125/54002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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50
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Ota N, Yalikun Y, Suzuki T, Lee SW, Hosokawa Y, Goda K, Tanaka Y. Enhancement in acoustic focusing of micro and nanoparticles by thinning a microfluidic device. ROYAL SOCIETY OPEN SCIENCE 2019; 6:181776. [PMID: 30891287 PMCID: PMC6408367 DOI: 10.1098/rsos.181776] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 01/23/2019] [Indexed: 05/04/2023]
Abstract
The manipulation of micro/nanoparticles has become increasingly important in biological and industrial fields. As a non-contact method for particle manipulation, acoustic focusing has been applied in sorting, enrichment and analysis of particles with microfluidic devices. Although the frequency and amplitude of acoustic waves and the dimensions of microchannels have been recognized as important parameters for acoustic focusing, the thickness of microfluidic devices has not been considered so far. Here, we report that thin glass microfluidic devices enhance acoustic focusing of micro/nanoparticles. It was found that the thickness of a microfluidic device strongly influences its ability to focus particles via acoustic radiation, because the energy propagation of acoustic waves is affected by the total mass of the device. Acoustic focusing of submicrometre polystyrene beads and Escherichia coli as well as enrichment of polystyrene beads were achieved in glass microfluidic devices as thin as 0.4 mm. Modifying the thickness of a microfluidic device can thus serve as a critical parameter for acoustic focusing when conventional parameters to achieve this effect are kept unchanged. Thus, our findings enable new approaches to the design of novel microfluidic devices.
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Affiliation(s)
- Nobutoshi Ota
- Center for Biosystems Dynamics Research (BDR), RIKEN, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yaxiaer Yalikun
- Center for Biosystems Dynamics Research (BDR), RIKEN, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan
- Division of Materials Science, Nara Institute of Science and Technology, Ikoma, Takayama, Nara 630-0192, Japan
| | - Tomoyuki Suzuki
- Division of Materials Science, Nara Institute of Science and Technology, Ikoma, Takayama, Nara 630-0192, Japan
| | - Sang Wook Lee
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yoichiroh Hosokawa
- Division of Materials Science, Nara Institute of Science and Technology, Ikoma, Takayama, Nara 630-0192, Japan
| | - Keisuke Goda
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Japan Science and Technology Agency, 4-1-8, Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Yo Tanaka
- Center for Biosystems Dynamics Research (BDR), RIKEN, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan
- Author for correspondence: Yo Tanaka e-mail:
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