Flexible Microfluidics: Fundamentals, Recent Developments, and Applications

Micromachines - Tập 10 Số 12 - Trang 830
Hedieh Fallahi1, Jun Zhang1, Hoang‐Phuong Phan1, Nam‐Trung Nguyen1
1Queensland Micro and Nanotechnology Centre, Griffith University, Brisbane, QLD 4111, Australia

Tóm tắt

Miniaturization has been the driving force of scientific and technological advances over recent decades. Recently, flexibility has gained significant interest, particularly in miniaturization approaches for biomedical devices, wearable sensing technologies, and drug delivery. Flexible microfluidics is an emerging area that impacts upon a range of research areas including chemistry, electronics, biology, and medicine. Various materials with flexibility and stretchability have been used in flexible microfluidics. Flexible microchannels allow for strong fluid-structure interactions. Thus, they behave in a different way from rigid microchannels with fluid passing through them. This unique behaviour introduces new characteristics that can be deployed in microfluidic applications and functions such as valving, pumping, mixing, and separation. To date, a specialised review of flexible microfluidics that considers both the fundamentals and applications is missing in the literature. This review aims to provide a comprehensive summary including: (i) Materials used for fabrication of flexible microfluidics, (ii) basics and roles of flexibility on microfluidic functions, (iii) applications of flexible microfluidics in wearable electronics and biology, and (iv) future perspectives of flexible microfluidics. The review provides researchers and engineers with an extensive and updated understanding of the principles and applications of flexible microfluidics.

Từ khóa


Tài liệu tham khảo

Whitesides, 2006, The origins and the future of microfluidics, Nature, 442, 368, 10.1038/nature05058

Nguyen, N.-T., Wereley, S.T., and Shaegh, S.A.M. (2019). Fundamentals and Applications of Microfluidics, Artech House.

Tan, 2004, Design of microfluidic channel geometries for the control of droplet volume, chemical concentration, and sorting, Lab Chip, 4, 292, 10.1039/b403280m

Oh, 2006, A review of microvalves, J. Micromech. Microeng., 16, R13, 10.1088/0960-1317/16/5/R01

Laser, 2004, A review of micropumps, J. Micromech. Microeng., 14, R35, 10.1088/0960-1317/14/6/R01

Woias, 2005, Micropumps—Past, progress and future prospects, Sens. Actuators B Chem., 105, 28, 10.1016/S0925-4005(04)00108-X

Nguyen, 2002, MEMS-micropumps: A review, J. Fluid. Eng.-T Asme., 124, 384, 10.1115/1.1459075

Nguyen, 2004, Micromixers—A review, J. Micromech. Microeng., 15, R1, 10.1088/0960-1317/15/2/R01

Hessel, 2005, Micromixers—A review on passive and active mixing principles, Chem. Eng. Sci., 60, 2479, 10.1016/j.ces.2004.11.033

Suh, 2010, A Review on Mixing in Microfluidics, Micromachines, 1, 82, 10.3390/mi1030082

Cai, G., Xue, L., Zhang, H., and Lin, J. (2017). A Review on Micromixers. Micromachines, 8.

Sajeesh, 2014, Particle separation and sorting in microfluidic devices: A review, Microfluid. Nanofluid., 17, 1, 10.1007/s10404-013-1291-9

Antfolk, 2017, Continuous flow microfluidic separation and processing of rare cells and bioparticles found in blood–A review, Anal. Chim. Acta, 965, 9, 10.1016/j.aca.2017.02.017

Gunther, 2006, Multiphase microfluidics: From flow characteristics to chemical and materials synthesis, Lab Chip, 6, 1487, 10.1039/B609851G

Marre, 2012, Supercritical microfluidics: Opportunities in flow-through chemistry and materials science, J. Supercrit. Fluid., 66, 251, 10.1016/j.supflu.2011.11.029

Marre, 2010, Synthesis of micro and nanostructures in microfluidic systems, Chem. Soc. Rev., 39, 1183, 10.1039/b821324k

Dendukuri, 2005, Controlled synthesis of nonspherical microparticles using microfluidics, Langmuir, 21, 2113, 10.1021/la047368k

Beebe, 2002, Physics and applications of microfluidics in biology, Annu. Rev. Biomed. Eng., 4, 261, 10.1146/annurev.bioeng.4.112601.125916

Lu, C., and Verbridge, S.S. (2016). Microfluidic Methods for Molecular Biology, Springer.

Bhagat, 2010, Microfluidics for cell separation, Med. Biol. Eng. Comput., 48, 999, 10.1007/s11517-010-0611-4

Huh, 2005, Microfluidics for flow cytometric analysis of cells and particles, Physiol. Meas., 26, R73, 10.1088/0967-3334/26/3/R02

Mazutis, 2013, Single-cell analysis and sorting using droplet-based microfluidics, Nat. Protoc., 8, 870, 10.1038/nprot.2013.046

Ziaie, 2004, Hard and soft micromachining for BioMEMS: Review of techniques and examples of applications in microfluidics and drug delivery, Adv. Drug Deliv. Rev., 56, 145, 10.1016/j.addr.2003.09.001

Gross, 2007, Applications of microfluidics for neuronal studies, J. Neurol. Sci., 252, 135, 10.1016/j.jns.2006.11.009

Wise, 2004, Wireless implantable microsystems: High-density electronic interfaces to the nervous system, Proc. IEEE, 92, 76, 10.1109/JPROC.2003.820544

Riahi, 2015, Microfluidics for Advanced Drug Delivery Systems, Curr. Opin. Chem. Eng., 7, 101, 10.1016/j.coche.2014.12.001

Yeo, 2016, Wearable tactile sensor based on flexible microfluidics, Lab Chip, 16, 3244, 10.1039/C6LC00579A

Gao, 2017, Wearable Microfluidic Diaphragm Pressure Sensor for Health and Tactile Touch Monitoring, Adv. Mater., 29, 1701985, 10.1002/adma.201701985

Zhang, 2013, Flexible packaging of solid-state integrated circuit chips with elastomeric microfluidics, Sci. Rep., 3, 1098, 10.1038/srep01098

Koh, 2016, A soft, wearable microfluidic device for the capture, storage, and colorimetric sensing of sweat, Sci. Transl. Med., 8, 366ra165, 10.1126/scitranslmed.aaf2593

Karabacak, 2014, Microfluidic, marker-free isolation of circulating tumor cells from blood samples, Nat. Protoc., 9, 694, 10.1038/nprot.2014.044

Erickson, 2004, Integrated microfluidic devices, Anal. Chim. Acta, 507, 11, 10.1016/j.aca.2003.09.019

Srinivasan, 2004, An integrated digital microfluidic lab-on-a-chip for clinical diagnostics on human physiological fluids, Lab Chip, 4, 310, 10.1039/b403341h

Abgrall, 2007, Lab-on-chip technologies: Making a microfluidic network and coupling it into a complete microsystem—A review, J. Micromech. Microeng., 17, R15, 10.1088/0960-1317/17/5/R01

Manz, 1992, Planar Chips Technology for Miniaturization and Integration of Separation Techniques into Monitoring Systems—Capillary Electrophoresis on a Chip, J. Chromatogr. A, 593, 253, 10.1016/0021-9673(92)80293-4

Rodriguez, 2003, Rapid prototyping of glass microchannels, Anal. Chim. Acta, 496, 205, 10.1016/S0003-2670(03)01000-6

Tabeling, P. (2005). Introduction to Microfluidics, OUP Oxford.

Gravesen, 1993, Microfluidics-a review, J. Micromech. Microeng., 3, 168, 10.1088/0960-1317/3/4/002

Hardy, 2009, The deformation of flexible PDMS microchannels under a pressure driven flow, Lab Chip, 9, 935, 10.1039/B813061B

Raj, 2016, Flow-induced deformation of compliant microchannels and its effect on pressure–flow characteristics, Microfluid. Nanofluid., 20, 31, 10.1007/s10404-016-1702-9

Verma, 2012, A dynamical instability due to fluid–wall coupling lowers the transition Reynolds number in the flow through a flexible tube, J. Fluid. Mech., 705, 322, 10.1017/jfm.2011.55

2016, Emergence of microfluidic wearable technologies, Lab Chip, 16, 4082, 10.1039/C6LC00926C

Cheng, 2012, Microfluidic electronics, Lab Chip, 12, 2782, 10.1039/c2lc21176a

Vogt, 2013, Design and Characterization of a Soft Multi-Axis Force Sensor Using Embedded Microfluidic Channels, IEEE Sens. J., 13, 4056, 10.1109/JSEN.2013.2272320

Li, 2014, Microflotronics: A Flexible, Transparent, Pressure-Sensitive Microfluidic Film, Adv. Funct. Mater., 24, 6195, 10.1002/adfm.201401527

Marquez, 2019, Building of a flexible microfluidic plasmo-nanomechanical biosensor for live cell analysis, Sens. Actuators B Chem., 291, 48, 10.1016/j.snb.2019.04.038

Andersson, 2003, Microfluidic devices for cellomics: A review, Sens. Actuators B Chem., 92, 315, 10.1016/S0925-4005(03)00266-1

Dabaghi, 2018, An ultra-thin highly flexible microfluidic device for blood oxygenation, Lab Chip, 18, 3780, 10.1039/C8LC01083H

Dong, 2019, Microfluidics-based biomaterials and biodevices, Adv. Mater., 31, e1805033, 10.1002/adma.201805033

Shimizu, A., Goh, W.H., Hashimoto, M., Miura, S., and Onoe, H. (2019, January 23–27). ECM-based Stretchable Microfluidic System for in vitro 3D Tissue Culture. Proceedings of the 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII), Berlin, Germany.

Hou, 2017, Interplay between materials and microfluidics, Nat. Rev. Mater., 2, 17016, 10.1038/natrevmats.2017.16

Tsao, C.W. (2016). Polymer Microfluidics: Simple, Low-Cost Fabrication Process Bridging Academic Lab Research to Commercialized Production. Micromachines, 7.

Nge, 2013, Advances in microfluidic materials, functions, integration, and applications, Chem. Rev., 113, 2550, 10.1021/cr300337x

Shang, 2017, Emerging Droplet Microfluidics, Chem. Rev., 117, 7964, 10.1021/acs.chemrev.6b00848

Naderi, 2019, Digital Manufacturing for Microfluidics, Annu. Rev. Biomed. Eng., 21, 325, 10.1146/annurev-bioeng-092618-020341

Pascault, J.-P., Sautereau, H., Verdu, J., and Williams, R.J. (2002). Thermosetting Polymers, CRC Press.

Tsao, 2009, Bonding of thermoplastic polymer microfluidics, Microfluid. Nanofluid., 6, 1, 10.1007/s10404-008-0361-x

McKeen, L.W. (2018). The Effect of Sterilization on Plastics and Elastomers, William Andrew.

Morton, M. (1987). Thermoplastic Elastomers. Rubber Technology, Springer.

Buschow, 2001, Encyclopedia of materials, Sci. Technol., 1, 11

Clarson, 1985, Studies of Cyclic and Linear Poly(Dimethylsiloxanes): 19. Glass-Transition Temperatures and Crystallization Behavior, Polymer, 26, 930, 10.1016/0032-3861(85)90140-5

Lotters, 1997, The mechanical properties of the rubber elastic polymer polydimethylsiloxane for sensor applications, J. Micromech. Microeng., 7, 145, 10.1088/0960-1317/7/3/017

Martin, 2017, Transparent, wear-resistant, superhydrophobic and superoleophobic poly(dimethylsiloxane) (PDMS) surfaces, J. Colloid. Interface Sci., 488, 118, 10.1016/j.jcis.2016.10.094

Abkarian, 2008, Cellular-scale hydrodynamics, Biomed. Mater., 3, 034011, 10.1088/1748-6041/3/3/034011

Bento, D., Rodrigues, R.O., Faustino, V., Pinho, D., Fernandes, C.S., Pereira, A.I., Garcia, V., Miranda, J.M., and Lima, R. (2018). Deformation of Red Blood Cells, Air Bubbles, and Droplets in Microfluidic Devices: Flow Visualizations and Measurements. Micromachines, 9.

Catarino, S.O., Rodrigues, R.O., Pinho, D., Miranda, J.M., Minas, G., and Lima, R. (2019). Blood Cells Separation and Sorting Techniques of Passive Microfluidic Devices: From Fabrication to Applications. Micromachines, 10.

Sackmann, 2014, The present and future role of microfluidics in biomedical research, Nature, 507, 181, 10.1038/nature13118

Tripathi, 2015, Passive blood plasma separation at the microscale: A review of design principles and microdevices, J. Micromech. Microeng., 25, 083001, 10.1088/0960-1317/25/8/083001

Ryu, 2015, Development of highly durable and low friction micro-structured PDMS coating based on bio-inspired surface design, Cirp. Ann-Manuf. Technol., 64, 519, 10.1016/j.cirp.2015.03.004

Lamberti, 2014, PDMS membranes with tunable gas permeability for microfluidic applications, Rsc Adv., 4, 61415, 10.1039/C4RA12934B

Bhattacharya, 2005, Studies on surface wettability of poly(dimethyl) siloxane (PDMS) and glass under oxygen-plasma treatment and correlation with bond strength, J. Microelectromech. Syst., 14, 590, 10.1109/JMEMS.2005.844746

Abate, 2008, Glass coating for PDMS microfluidic channels by sol–gel methods, Lab Chip, 8, 516, 10.1039/b800001h

Eddington, 2006, Thermal aging and reduced hydrophobic recovery of polydimethylsiloxane, Sens. Actuators B Chem., 114, 170, 10.1016/j.snb.2005.04.037

Halldorsson, 2015, Advantages and challenges of microfluidic cell culture in polydimethylsiloxane devices, Biosens. Bioelectron., 63, 218, 10.1016/j.bios.2014.07.029

Eddings, 2008, Determining the optimal PDMS–PDMS bonding technique for microfluidic devices, J. Micromech. Microeng., 18, 067001, 10.1088/0960-1317/18/6/067001

Vlachopoulou, 2009, Effect of surface nanostructuring of PDMS on wetting properties, hydrophobic recovery and protein adsorption, Microelectron. Eng., 86, 1321, 10.1016/j.mee.2008.11.050

Yeo, 2016, Highly Flexible Graphene Oxide Nanosuspension Liquid-Based Microfluidic Tactile Sensor, Small, 12, 1593, 10.1002/smll.201502911

Kubo, 2010, Stretchable microfluidic radiofrequency antennas, Adv. Mater., 22, 2749, 10.1002/adma.200904201

Huang, J., Zhang, C., Ding, G., Yang, Z., Zhao, X., Liu, Y., Tang, Z., Shao, X., Yang, S., and Lin, X. (2019, January 23–27). A High-Sensitivity Microfluidic Chip Calorimeter for Biochemical Reaction Monitoring Applications. Proceedings of the 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII), Berlin, Germany.

Jeon, 2002, Microfluidics section: Design and fabrication of integrated passive valves and pumps for flexible polymer 3-dimensional microfluidic systems, Biomed. Microdevices, 4, 117, 10.1023/A:1014683114796

Yin, 2017, Bioinspired flexible microfluidic shear force sensor skin, Sens. Actuators A-Phys., 264, 289, 10.1016/j.sna.2017.08.001

Wong, 2012, Flexible microfluidic normal force sensor skin for tactile feedback, Sens. Actuators A-Phys., 179, 62, 10.1016/j.sna.2012.03.023

Hur, 2018, 3D Micropatterned All-Flexible Microfluidic Platform for Microwave-Assisted Flow Organic Synthesis, ChemPlusChem, 83, 42, 10.1002/cplu.201700440

Kuppusami, 2015, Parylene coatings in medical devices and implants: A review, J. Med. Biol. Eng., 3, 9

Foley, 2009, Flexible microfluidic devices supported by biodegradable insertion scaffolds for convection-enhanced neural drug delivery, Biomed. Microdevices, 11, 915, 10.1007/s10544-009-9308-6

Ziegler, 2006, Fabrication of flexible neural probes with built-in microfluidic channels by thermal bonding of Parylene, J. Microelectromech. Syst., 15, 1477, 10.1109/JMEMS.2006.879681

Takeuchi, 2005, Parylene flexible neural probes integrated with microfluidic channels, Lab Chip, 5, 519, 10.1039/b417497f

Pellinen, D.S., Moon, T., Vetter, R., Miriani, R., and Kipke, D.R. (2006, January 17–18). Multifunctional flexible parylene-based intracortical microelectrodes. Proceedings of the 2005 IEEE Engineering in Medicine and Biology 27th Annual Conference, Shanghai, China.

Seo, 2019, Parylene based thin-film microfluidic lens array fabricated by iCVD nano-adhesive bonding, Polymer, 181, 121763, 10.1016/j.polymer.2019.121763

Jung, B.J., Kim, J., Kim, J.A., Jang, H., Seo, S., and Lee, W. (2018). PDMS-Parylene Hybrid, Flexible Microfluidics for Real-Time Modulation of 3D Helical Inertial Microfluidics. Micromachines, 9.

Lin, 2019, A rapid and low-cost fabrication and integration scheme to render 3D microfluidic architectures for wearable biofluid sampling, manipulation, and sensing, Lab Chip, 19, 2844, 10.1039/C9LC00418A

Demuru, S., Haque, R., Joho, M.O., Bionaz, A., van der Wal, P., and Briand, D. (2019, January 23–27). 3D-Integration of Printed Electrochemical Sensors in Pet Microfluidics for Biochemical Sensing. Proceedings of the 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII), Berlin, Germany.

Metz, 2001, Polyimide-based microfluidic devices, Lab Chip, 1, 29, 10.1039/b103896f

(2003). Polyimide microfluidic devices with integrated nanoporous filtration areas manufactured by micromachining and ion track technology. J. Micromech. Microeng., 14, 324.

Metz, 2004, Polyimide and SU-8 microfluidic devices manufactured by heat-depolymerizable sacrificial material technique, Lab Chip, 4, 114, 10.1039/b310866j

Sempionatto, 2019, Skin-worn Soft Microfluidic Potentiometric Detection System, Electroanalysis, 31, 239, 10.1002/elan.201800414

Metz, S., Trautmann, C., Bertsch, A., and Renaud, P. (2002, January 24). Flexible microchannels with integrated nanoporous membranes for filtration and separation of molecules and particles. Proceedings of the Technical Digest. MEMS 2002 IEEE International Conference. Fifteenth IEEE International Conference on Micro Electro Mechanical Systems (Cat. No. 02CH37266), Las Vegas, NV, USA.

Metz, 2004, Flexible polyimide probes with microelectrodes and embedded microfluidic channels for simultaneous drug delivery and multi-channel monitoring of bioelectric activity, Biosens. Bioelectron., 19, 1309, 10.1016/j.bios.2003.11.021

Phan, 2019, Long-Lived, Transferred Crystalline Silicon Carbide Nanomembranes for Implantable Flexible Electronics, ACS Nano, 13, 11572, 10.1021/acsnano.9b05168

Zulfiqar, 2015, Fabrication of polyimide based microfluidic channels for biosensor devices, J. Micromech. Microeng., 25, 035022, 10.1088/0960-1317/25/3/035022

Wego, 2001, A self-filling micropump based on PCB technology, Sens. Actuators A-Phys, 88, 220, 10.1016/S0924-4247(00)00519-7

Boden, 2006, A polymeric paraffin actuated high-pressure micropump, Sens. Actuators A-Phys, 127, 88, 10.1016/j.sna.2005.11.068

Komatsuzaki, H., Suzuki, K., Liu, Y.W., Kosugi, T., Ikoma, R., Youn, S.W., Takahashi, M., Maeda, R., and Nishioka, Y. (2011). Flexible Polyimide Micropump Fabricated Using Hot Embossing. Jpn. J. Appl. Phys., 50.

Min, 2010, Monolithic and flexible polyimide film microreactors for organic microchemical applications fabricated by laser ablation, Angew. Chem. Int. Ed. Engl., 49, 7063, 10.1002/anie.201002004

Carlborg, 2011, Beyond PDMS: Off-stoichiometry thiol–ene (OSTE) based soft lithography for rapid prototyping of microfluidic devices, Lab Chip, 11, 3136, 10.1039/c1lc20388f

Saharil, 2012, Biocompatible “click” wafer bonding for microfluidic devices, Lab Chip, 12, 3032, 10.1039/c2lc21098c

Good, 2007, Tailorable low modulus, reversibly deformable elastomeric thiol–ene materials for microfluidic applications, Sens. Actuators B Chem., 120, 473, 10.1016/j.snb.2006.02.040

Chen, 2015, UV-nanoimprint lithography as a tool to develop flexible microfluidic devices for electrochemical detection, Lab Chip, 15, 3086, 10.1039/C5LC00515A

Chang, 2008, A flexible piezoelectric sensor for microfluidic applications using polyvinylidene fluoride, IEEE Sens. J., 8, 495, 10.1109/JSEN.2008.918749

Lin, 2011, Organic electrochemical transistors integrated in flexible microfluidic systems and used for label-free DNA sensing, Adv. Mater., 23, 4035, 10.1002/adma.201102017

Nelson, 2019, Flexible, transparent, sub-100 µm microfluidic channels with fused deposition modeling 3D-printed thermoplastic polyurethane, J. Micromech. Microeng., 29, 095010, 10.1088/1361-6439/ab2f26

Li, 2012, A perspective on paper-based microfluidics: Current status and future trends, Biomicrofluidics, 6, 11301, 10.1063/1.3687398

Gong, 2017, Turning the Page: Advancing Paper-Based Microfluidics for Broad Diagnostic Application, Chem. Rev., 117, 8447, 10.1021/acs.chemrev.7b00024

Eom, S., and Lim, S. (2016). Stretchable Complementary Split Ring Resonator (CSRR)-Based Radio Frequency (RF) Sensor for Strain Direction and Level Detection. Sensors, 16.

Jeong, 2016, PDMS-based elastomer tuned soft, stretchable, and sticky for epidermal electronics, Adv. Mater., 28, 5830, 10.1002/adma.201505372

Noh, 2004, Wafer bonding using microwave heating of parylene intermediate layers, J. Micromech. Microeng., 14, 625, 10.1088/0960-1317/14/4/025

Kim, J.H., You, J.B., Im, S.G., and Lee, W.H. (2015, January 25–29). Molding and bonding of thin film parylene for flexible microfluidics. Proceedings of the InterPACK/ICNMM 2015, Gyeongju, Korea.

Foulds, I.G., Conchouso, D., and Castro, D. (2015). Microfluidic Device for High-Volume Production and Processing of Monodisperse Emulsions. (2015068045A3), WO Patent.

Derix, 2009, Porous polyethylene terephthalate membranes in microfluidic applications, Phys. Status Solidi. A, 206, 442, 10.1002/pssa.200880479

Raj, 2018, Pressure-driven flow through PDMS-based flexible microchannels and their applications in microfluidics, Microfluid. Nanofluid., 22, 128, 10.1007/s10404-018-2150-5

Wang, X., and Christov, I.C. (2019). Theory of the flow-induced deformation of shallow compliant microchannels with thick walls. Proc. Royal. Soc. Lond., 475.

Ozsun, O., Yakhot, V., and Ekinci, K.L. (2013). Non-invasive measurement of the pressure distribution in a deformable micro-channel. J. Fluid. Mech., 734.

Gervais, 2006, Flow-induced deformation of shallow microfluidic channels, Lab Chip, 6, 500, 10.1039/b513524a

Christov, 2018, Flow rate-pressure drop relation for deformable shallow microfluidic channels, J. Fluid. Mech., 841, 267, 10.1017/jfm.2018.30

Adzima, 2006, Pressure drops for droplet flows in microfluidic channels, J. Micromech. Microeng., 16, 1504, 10.1088/0960-1317/16/8/010

Cheung, 2012, In situ pressure measurement within deformable rectangular polydimethylsiloxane microfluidic devices, Biomicrofluidics, 6, 026501, 10.1063/1.4720394

Raj, 2017, Hydrodynamics in deformable microchannels, Microfluid. Nanofluid., 21, 70, 10.1007/s10404-017-1908-5

Shidhore, 2018, Static response of deformable microchannels: A comparative modelling study, J. Phys. Condens. Matter., 30, 054002, 10.1088/1361-648X/aaa226

Ottino, 2004, Introduction: Mixing in microfluidics, Phil. Trans. R. Soc. Lond. A, 2004, 923, 10.1098/rsta.2003.1355

Srinivas, 2017, Effect of viscoelasticity on the soft-wall transition and turbulence in a microchannel, J. Fluid. Mech., 812, 1076, 10.1017/jfm.2016.839

Raj, 2018, Flow-induced deformation in a microchannel with a non-Newtonian fluid, Biomicrofluidics, 12, 034116, 10.1063/1.5036632

Patne, 2017, Consistent formulations for stability of fluid flow through deformable channels and tubes, J. Fluid. Mech., 827, 31, 10.1017/jfm.2017.485

Srinivas, 2017, Transitions to different kinds of turbulence in a channel with soft walls, J. Fluid. Mech., 822, 267, 10.1017/jfm.2017.270

Kumaran, 2016, Ultra-fast microfluidic mixing by soft-wall turbulence, Chem. Eng. Sci., 149, 156, 10.1016/j.ces.2016.04.001

Verma, 2013, A multifold reduction in the transition Reynolds number, and ultra-fast mixing, in a micro-channel due to a dynamical instability induced by a soft wall, J. Fluid. Mech., 727, 407, 10.1017/jfm.2013.264

Verma, 2015, Effect of ultra-fast mixing in a microchannel due to a soft wall on the room temperature synthesis of gold nanoparticles, Sadhana-Acad. Proc. Eng. Sci., 40, 973

Terray, 2002, Microfluidic control using colloidal devices, Science, 296, 1841, 10.1126/science.1072133

Baek, 2005, A pneumatically controllable flexible and polymeric microfluidic valve fabricated via in situ development, J. Micromech. Microeng., 15, 1015, 10.1088/0960-1317/15/5/017

Unger, 2000, Monolithic microfabricated valves and pumps by multilayer soft lithography, Science, 288, 113, 10.1126/science.288.5463.113

Holmes, 2013, Control and manipulation of microfluidic flow via elastic deformations, Soft Matter, 9, 7049, 10.1039/C3SM51002F

Holmes, 2019, Elasticity and Stability of Shape Changing Structures, Curr. Opin. Colloid. Interface Sci., 40, 118, 10.1016/j.cocis.2019.02.008

Gomez, 2017, Passive Control of Viscous Flow via Elastic Snap-Through, Phys. Rev. Lett., 119, 144502, 10.1103/PhysRevLett.119.144502

Gomez, 2019, Dynamics of viscoelastic snap-through, J. Mech. Phys. Solids, 124, 781, 10.1016/j.jmps.2018.11.020

Inamdar, T.C. (2018). Unsteady Fluid-Structure Interactions in Soft-Walled Microchannels, Purdue University.

Gomez, M. (2018). Ghosts and Bottlenecks in Elastic Snap-Through, University of Oxford.

Mohith, 2019, Recent trends in mechanical micropumps and their applications: A review, Mechatronics, 60, 34, 10.1016/j.mechatronics.2019.04.009

Tavakol, 2014, Buckling of dielectric elastomeric plates for soft, electrically active microfluidic pumps, Soft Matter, 10, 4789, 10.1039/C4SM00753K

Liu, 2017, Deflection behavior of a piezo-driven flexible actuator for vacuum micropumps, Sens. Actuators A-Phys, 267, 30, 10.1016/j.sna.2017.09.029

Bengtsson, 2017, A large-area, all-plastic, flexible electroosmotic pump, Microfluid. Nanofluid., 21, 178, 10.1007/s10404-017-2017-1

2018, Pressure-actuated monolithic acrylic microfluidic valves and pumps, Lab Chip, 18, 662, 10.1039/C7LC01337J

Wu, 2005, TITAN: A conducting polymer based microfluidic pump, Smart Mater. Struct., 14, 1511, 10.1088/0964-1726/14/6/043

Ma, 2019, Piezoelectric peristaltic micropump integrated on a microfluidic chip, Sens. Actuators A-Phys, 292, 90, 10.1016/j.sna.2019.04.005

Iverson, 2008, Recent advances in microscale pumping technologies: A review and evaluation, Microfluid. Nanofluid., 5, 145, 10.1007/s10404-008-0266-8

Jeong, 2005, Fabrication of a peristaltic PDMS micropump, Sens. Actuators A-Phys., 123–124, 453, 10.1016/j.sna.2005.01.035

Xiang, 2016, A micro-cam actuated linear peristaltic pump for microfluidic applications, Sens. Actuators A-Phys, 251, 20, 10.1016/j.sna.2016.09.008

Shutko, 2017, Biocontractile microfluidic channels for peristaltic pumping, Biomed. Microdevices, 19, 72, 10.1007/s10544-017-0216-x

Hatipoglu, 2018, A novel zero-dead-volume sample loading interface for microfluidic devices: Flexible hydraulic reservoir (FHR), J. Micromech. Microeng., 28, 097001, 10.1088/1361-6439/aac333

Lin, 2019, Acoustofluidic stick-and-play micropump built on foil for single-cell trapping, Lab Chip, 19, 3045, 10.1039/C9LC00484J

Zhao, 2017, High-throughput sheathless and three-dimensional microparticle focusing using a microchannel with arc-shaped groove arrays, Sci. Rep., 7, 41153, 10.1038/srep41153

Lenshof, 2010, Continuous separation of cells and particles in microfluidic systems, Chem. Soc. Rev., 39, 1203, 10.1039/b915999c

Dalili, 2018, A review of sorting, separation and isolation of cells and microbeads for biomedical applications: Microfluidic approaches, Analyst, 144, 87, 10.1039/C8AN01061G

Yan, 2015, An integrated dielectrophoresis-active hydrophoretic microchip for continuous particle filtration and separation, J. Micromech. Microeng., 25, 084010, 10.1088/0960-1317/25/8/084010

Yan, 2015, A hybrid dielectrophoretic and hydrophoretic microchip for particle sorting using integrated prefocusing and sorting steps, Electrophoresis, 36, 284, 10.1002/elps.201400397

Zhang, 2016, Fundamentals and applications of inertial microfluidics: A review, Lab Chip, 16, 10, 10.1039/C5LC01159K

Zhang, 2018, Tunable particle separation in a hybrid dielectrophoresis (DEP)-inertial microfluidic device, Sens. Actuators B Chem., 267, 14, 10.1016/j.snb.2018.04.020

Chung, 2019, A Minireview on Inertial Microfluidics Fundamentals: Inertial Particle Focusing and Secondary Flow, Biochip J., 13, 53, 10.1007/s13206-019-3110-1

Irimia, 2007, Continuous inertial focusing, ordering, and separation of particles in microchannels, Proc. Natl. Acad. Sci. USA, 104, 18892, 10.1073/pnas.0704958104

2009, Inertial microfluidics, Lab Chip, 9, 3038, 10.1039/b912547g

Xi, 2017, Soft tubular microfluidics for 2D and 3D applications, Proc. Natl. Acad. Sci. USA, 114, 10590, 10.1073/pnas.1712195114

Hahn, Y.K., Hong, D., Kang, J.H., and Choi, S. (2016). A reconfigurable microfluidics platform for microparticle separation and fluid mixing. Micromachines, 7.

Dickey, 2008, Eutectic gallium-indium (EGaIn): A liquid metal alloy for the formation of stable structures in microchannels at room temperature, Adv. Funct. Mater., 18, 1097, 10.1002/adfm.200701216

Asghari, M., Serhatlioglu, M., Saritas, R., Guler, M.T., and Elbuken, C. (2019). Tape’n Roll Inertial Microfluidics. Sens. Actuators A-Phys., 111630.

Yeo, 2016, Triple-State Liquid-Based Microfluidic Tactile Sensor with High Flexibility, Durability, and Sensitivity, ACS Sens., 1, 543, 10.1021/acssensors.6b00115

Xu, 2014, Soft microfluidic assemblies of sensors, circuits, and radios for the skin, Science, 344, 70, 10.1126/science.1250169

Jung, 2015, Highly stable liquid metal-based pressure sensor integrated with a microfluidic channel, Sensors, 15, 11823, 10.3390/s150511823

Alfadhel, 2018, Inkjet printed polyethylene glycol as a fugitive ink for the fabrication of flexible microfluidic systems, Mater. Des., 150, 182, 10.1016/j.matdes.2018.04.013

Kim, 2018, Soft, Skin-Interfaced Microfluidic Systems with Wireless, Battery-Free Electronics for Digital, Real-Time Tracking of Sweat Loss and Electrolyte Composition, Small, 14, e1802876, 10.1002/smll.201802876

Ota, 2014, Highly deformable liquid-state heterojunction sensors, Nat. Commun., 5, 5032, 10.1038/ncomms6032

Wang, Q.F., Gao, M., Zhang, L.J., Deng, Z.S., and Gui, L. (2019). A Handy Flexible Micro-Thermocouple Using Low-Melting-Point Metal Alloys. Sensors, 19.

Yoon, 2017, Microfluidic capacitive sensors with ionic liquid electrodes and CNT/PDMS nanocomposites for simultaneous sensing of pressure and temperature, J. Mater. Chem. C, 5, 1910, 10.1039/C6TC03994D

Sun, 2018, Highly transparent and flexible circuits through patterning silver nanowires into microfluidic channels, Chem. Commun., 54, 4923, 10.1039/C8CC01438H

Fallahi, 2017, Preparation and properties of electrically conductive, flexible and transparent silver nanowire/poly (lactic acid) nanocomposites, Org. Electron., 44, 74, 10.1016/j.orgel.2017.01.043

Satoungar, 2016, Effect of Different Mediated Agents on Morphology and Crystallinity of Synthesized Silver Nanowires Prepared by Polyol Process, J. Nanomater., 2016, 5, 10.1155/2016/4354136

Azizi, H., Fallahi, H., Ghasemi, I., Karrabi, M., and Nazemian, M. (2014, January 6–9). Silane Modification of Carbon Nanotubes and Preparation of Silane Cross-Linked LLDPE/MWCNT Nanocomposites. Proceedings of the 11th International Seminar on Polymer Science and Technology, Tehran, Iran.

Wu, 2018, Bioinspired Universal Flexible Elastomer-Based Microchannels, Small, 14, e1702170, 10.1002/smll.201702170

Silva, 2016, Generation of micro-sized PDMS particles by a flow focusing technique for biomicrofluidics applications, Biomicrofluidics, 10, 014122, 10.1063/1.4943007

Pinho, 2019, Flexible PDMS microparticles to mimic RBCs in blood particulate analogue fluids, Mech. Res. Commun., 100, 103399, 10.1016/j.mechrescom.2019.103399

Hasan, 2018, One-step fabrication of flexible nanotextured PDMS as a substrate for selective cell capture, Biomed. Phys. Eng. Express, 4, 025015, 10.1088/2057-1976/aa89a6

Minev, 2015, Biomaterials. Electronic dura mater for long-term multimodal neural interfaces, Science, 347, 159, 10.1126/science.1260318

Jeong, J.-W., McCall, J.G., Zhang, Y., Huang, Y., Bruchas, M., and Rogers, J.A. (2015, January 21–25). Soft microfluidic neural probes for wireless drug delivery in freely behaving mice. Proceedings of the 2015 Transducers-2015 18th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS), Anchorage, AK, USA.

Sim, 2017, Microfluidic neural probes: In vivo tools for advancing neuroscience, Lab Chip, 17, 1406, 10.1039/C7LC00103G

Liu, 2019, Ultrastretchable and Wireless Bioelectronics Based on All-Hydrogel Microfluidics, Adv. Mater., 31, e1902783, 10.1002/adma.201902783

Yuk, 2016, Skin-inspired hydrogel–elastomer hybrids with robust interfaces and functional microstructures, Nat. Commun., 7, 12028, 10.1038/ncomms12028

Guo, 2019, Conductive Polymer Hydrogel Microfibers from Multiflow Microfluidics, Small, 15, e1805162, 10.1002/smll.201805162