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High-throughput preparation of uniform tiny droplets in multiple capillaries embedded stepwise microchannels


Microfluidic technologies are reliable methods to obtain uniform and tiny droplets, but their application is limited by the capacity of single microchannel and the difficulty in fabrication and operation of large amounts of parallel droplet generators. Here, we reported a microchannel device equipped with multiple capillaries for rupturing the dispersed fluid, which realized droplet generation frequency up to 40 kHz in a single microchannel. The microchannel was operated under jetting flow, which was robust for controlling the droplet size uniformity; therefore, the device did not need highly precise machinery and accurate installation during fabrication. 30–100 μm droplets with CV <5% were successfully prepared in a 20-capillary embedded microchannel device with high throughput, verifying the effectiveness of improving the working ability of micro-channel unit in the scale-up of microfluidic device.

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  1. 1.

    Shang L, Fu F, Cheng Y, Wang H, Liu Y, Zhao Y, Gu Z (2015) Photonic crystal microbubbles as suspension barcodes. J Am Chem Soc 137(49):15533–15539.

  2. 2.

    Wang J, Hu Y, Deng R, Xu W, Liu S, Liang R, Nie Z, Zhu J (2012) Construction of multifunctional photonic crystal microcapsules with tunable shell structures by combining microfluidic and controlled photopolymerization. Lab Chip 12(16):2795–2798.

  3. 3.

    Park JI, Nie Z, Kumachev A, Abdelrahman AI, Binks BP, Stone HA, Kumacheva E (2009) A microfluidic approach to chemically driven assembly of colloidal particles at gas-liquid interfaces. Angew Chem Int Edit 48(29):5300–5304.

  4. 4.

    Sun C, Takegawa N (2018) Calibration of a particle mass spectrometer using polydispersed aerosol particles. Aerosol Sci Technol 53(1):1–7.

  5. 5.

    Shimada M, Chang H, Fujishige Y, Okuyama K (2001) Calibration of polarization-sensitive and dual-angle laser light scattering methods using standard latex particles. J Colloid Interface Sci 241(1):71–80.

  6. 6.

    Fu T, Ma Y, Funfschilling D, Zhu C, Li HZ (2012) Breakup dynamics of slender bubbles in non-newtonian fluids in microfluidic flow-focusing devices. AICHE J 58(11):3560–3567.

  7. 7.

    Walsh PA, Egan VM, Walsh EJ (2009) Novel micro-PIV study enables a greater understanding of nanoparticle suspension flows: nanofluids. Microfluid Nanofluid 8(6):837–842.

  8. 8.

    Nisisako T (2008) Microstructured devices for preparing controlled multiple emulsions. Chem Eng Tech 31(8):1091–1098.

  9. 9.

    Zhu P, Wang L (2016) Passive and active droplet generation with microfluidics: a review. Lab Chip 17(1):34–75.

  10. 10.

    Gu H, Duits MH, Mugele F (2011) Droplets formation and merging in two-phase flow microfluidics. Int J Mol Sci 12(4):2572–2597.

  11. 11.

    Christopher GF, Anna SL (2007) Microfluidic methods for generating continuous droplet streams. J Phys D Appl Phys 40(19):R319–R336.

  12. 12.

    Li W, Young EWK, Seo M, Nie Z, Garstecki P, Simmons CA, Kumacheva E (2008) Simultaneous generation of droplets with different dimensions in parallel integrated microfluidic droplet generators. Soft Matter 4(2):258–262.

  13. 13.

    Shen Q, Zhang C, Tahir MF, Jiang S, Zhu C, Ma Y, Fu T (2018) Numbering-up strategies of micro-chemical process: uniformity of distribution of multiphase flow in parallel microchannels. Chem Eng Process 132:148–159.

  14. 14.

    Yap SK, Wong WK, Ng NXY, Khan SA (2017) Three-phase microfluidic reactor networks – design, modeling and application to scaled-out nanoparticle-catalyzed hydrogenations with online catalyst recovery and recycle. Chem Eng Sci 169:117–127.

  15. 15.

    Sugiura S, Nakajima M, Kumazawa N, Iwamoto S, Seki M (2002) Characterization of spontaneous transformation-based droplet formation during microchannel emulsification. J Phys Chem B 106(36):9405–9409.

  16. 16.

    Sugiura S, Nakajima M, Seki M (2002) Preparation of monodispersed polymeric microspheres over 50 μm employing microchannel emulsification. Ind Eng Chem Res 41(16):4043–4047.

  17. 17.

    Nisisako T, Torii T (2008) Microfluidic large-scale integration on a chip for mass production of monodisperse droplets and particles. Lab Chip 8(2):287–293.

  18. 18.

    Dong P-F, Xu J-H, Zhao H, Luo G-S (2013) Preparation of 10μm scale monodispersed particles by jetting flow in coaxial microfluidic devices. Chem Eng J 214:106–111.

  19. 19.

    Wang K, Lu YC, Xu JH, Tan J, Luo GS (2011) Generation of micromonodispersed droplets and bubbles in the capillary embedded T-junction microfluidic devices. AICHE J 57(2):299–306.

  20. 20.

    Wang K, Xie L, Lu Y, Luo G (2013) Generation of monodispersed microdroplets by temperature controlled bubble condensation processes. Lab Chip 13(1):73–76.

  21. 21.

    Yang L, Wang K, Mak S, Li Y, Luo G (2013) A novel microfluidic technology for the preparation of gas-in-oil-in-water emulsions. Lab Chip 13(17):3355–3359.

  22. 22.

    Li YK, Liu GT, Xu JH, Wang K, Luo GS (2015) A microdevice for producing monodispersed droplets under a jetting flow. RSC Adv 5(35):27356–27364.

  23. 23.

    Li YK, Wang K, Xu JH, Luo GS (2016) A capillary-assembled micro-device for monodispersed small bubble and droplet generation. Chem Eng J 293:182–188.

  24. 24.

    Li YK, Wang K, Luo GS (2017) Microdroplet generation with dilute surfactant concentration in a modified T-junction device. Ind Eng Chem Res 56(42):12131–12138.

  25. 25.

    Nisisako T, Ando T, Hatsuzawa T (2012) High-volume production of single and compound emulsions in a microfluidic parallelization arrangement coupled with coaxial annular world-to-chip interfaces. Lab Chip 12(18):3426–3435.

  26. 26.

    Kim M, Pan M, Gai Y, Pang S, Han C, Yang C, Tang SK (2015) Optofluidic ultrahigh-throughput detection of fluorescent drops. Lab Chip 15(6):1417–1423.

  27. 27.

    Lim J, Caen O, Vrignon J, Konrad M, Taly V, Baret JC (2015) Parallelized ultra-high throughput microfluidic emulsifier for multiplex kinetic assays. Biomicrofluidics 9(3):034101.

  28. 28.

    Wang K, Lu YC, Xu JH, Luo GS (2009) Determination of dynamic interfacial tension and its effect on droplet formation in the T-shaped microdispersion process. Langmuir 25(4):2153–2158.

  29. 29.

    Wang K, Zhang L, Zhang W, Luo G (2016) Mass-transfer-controlled dynamic interfacial tension in microfluidic emulsification processes. Langmuir 32(13):3174–3185.

  30. 30.

    Ushikubo FY, Birribilli FS, Oliveira DRB, Cunha RL (2014) Y- and T-junction microfluidic devices: effect of fluids and interface properties and operating conditions. Microfluid Nanofluid 17(4):711–720.

  31. 31.

    Wehking JD, Gabany M, Chew L, Kumar R (2013) Effects of viscosity, interfacial tension, and flow geometry on droplet formation in a microfluidic T-junction. Microfluid Nanofluid 16(3):441–453.

  32. 32.

    Utada AS, Fernandez-Nieves A, Gordillo JM, Weitz DA (2008) Absolute instability of a liquid jet in a coflowing stream. Phys Rev Lett 100(1):014502.

  33. 33.

    Utada AS, Fernandez-Nieves A, Stone HA, Weitz DA (2007) Dripping to jetting transitions in coflowing liquid streams. Phys Rev Lett 99(9):094502.

  34. 34.

    Li S, Xu J, Wang Y, Luo G (2009) A new interfacial tension measurement method through a pore array micro-structured device. J Colloid Interface Sci 331(1):127–131.

  35. 35.

    Dangla R, Kayi SC, Baroud CN (2013) Droplet microfluidics driven by gradients of confinement. Proc Natl Acad Sci 110(3):853–858.

  36. 36.

    Muluneh M, Issadore D (2013) Hybrid soft-lithography/laser machined microchips for the parallel generation of droplets. Lab Chip 13(24):4750–4754.

  37. 37.

    Amstad E, Chemama M, Eggersdorfer M, Arriaga LR, Brenner MP, Weitz DA (2016) Robust scalable high throughput production of monodisperse drops. Lab Chip 16(21):4163–4172.

  38. 38.

    Han T, Zhang L, Xu H, Xuan J (2017) Factory-on-chip: modularised microfluidic reactors for continuous mass production of functional materials. Chem Eng J 326:765–773.

  39. 39.

    Conchouso D, Castro D, Khan SA, Foulds IG (2014) Three-dimensional parallelization of microfluidic droplet generators for a litre per hour volume production of single emulsions. Lab Chip 14(16):3011–3020.

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We gratefully acknowledge the supports of the National Natural Science Foundation of China (21991104, 21776150) and National Key R&D Program of China (2017YFB0307102) on this work.

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Correspondence to Kai Wang or Guangsheng Luo.

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Article Highlights

1. Mass preparation of uniform droplets at 30-100 μm was realized by using low-cost microchannel device.

2. The jetting flow pattern was robust for controlling the droplet size and uniformity.

3. Droplet generation frequency up to 40 kHz was realized for a single microchannel embedded with 10-capillaries.

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Cui, Y., Li, Y., Wang, K. et al. High-throughput preparation of uniform tiny droplets in multiple capillaries embedded stepwise microchannels. J Flow Chem (2020).

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  • Droplet generation
  • High throughput
  • Microfluidics
  • Emulsification