Skip to main content
SpringerLink
Log in

A simple droplet merger design for controlled reaction volumes

  • Research Paper
  • Published:
Microfluidics and Nanofluidics Aims and scope Submit manuscript

Abstract

Droplet microfluidics has been proven to be a viable platform for a variety of reactions by using uniform droplets well encapsulated by an immiscible carrier medium as reaction vesicles. Merging as one of the most basic forms of droplet manipulation is highly demanded in controlling the concentration of reagents for reactions. After preliminary testing of several reported passive merging designs, it is found that most of them are prone to fabrication and operation uncertainties which limit their application for practical use. In this work, we present a simple design for merging variable numbers of droplets with a valve-type function which enables a critical volume limit to be imposed to the final product droplet. When the product droplet reaches the critical volume limit, it will block the exit of the merging chamber serving as the close mode of the valve. As a result, the pressure upstream is built up which forces the product droplet to exit the merger. The relationship between the numbers of droplets merged, the length of input droplets and the length of output droplets is used to tune the design parameters such as the chamber length, pillar array dimensions and bypass channel dimensions according to the desired set of reactions. The simplicity of the design allows for easier design and configuration to a desired purpose and lows down the risk of failures due to fabrication and operation uncertainties. The single-input–single-output design minimizes pressure disturbances from propagating downstream and reduces the complexity of integration into a larger LOC system. The geometry can be scaled up with little to no observable effect on the mode of operation.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

References

  • Abate AR, Hung T, Mary P, Agresti JJ, Weitz DA (2010) High-throughput injection with microfluidics using picoinjectors. Proc Natl Acad Sci 107:19163–19166

    Article  Google Scholar 

  • Basu AS (2013) Droplet morphometry and velocimetry (DMV): a video processing software for time-resolved, label-free tracking of droplet parameters. Lab Chip 13:1892–1901

    Article  Google Scholar 

  • Boybay MS, Jiao A, Glawdel T, Ren CL (2013) Microwave sensing and heating of individual droplets in microfluidic devices. Lab Chip 13:3840–3846

    Article  Google Scholar 

  • Bremond N, Thiam A, Bibette J (2008) Decompressing emulsion droplets favors coalescence. Phys Rev Lett 100:024501

    Article  Google Scholar 

  • Christopher GF, Bergstein J, End NB, Poon M, Nguyen C, Anna SL (2009) Coalescence and splitting of confined droplets at microfluidic junctions. Lab Chip 9:1102–1109

    Article  Google Scholar 

  • Dewan A, Kim J, Mclean RH, Vanapalli SA, Karim MN (2012) Growth kinetics of microalgae in microfluidic static droplet arrays. Biotechnol Bioeng 109:2987–2996

    Article  Google Scholar 

  • Frenz L, Harrak AEI, Pauly M, Colin SB, Griffiths AD, Baret JC (2008) Droplet-based microreactors for the synthesis of magnetic iron oxide nanoparticles. Angew Chem Int Ed 47:6817–6820

    Article  Google Scholar 

  • Garstecki P, Fuerstman MJ, Stone HA, Whitesides GM (2006) Formation of droplets and bubbles in a microfluidic T-junction-scaling and mechanism of break-up. Lab Chip 6:437–446

    Article  Google Scholar 

  • Glawdel T, Elbuken C, Ren C (2011) Passive droplet trafficking at microfluidic junctions under geometric and flow asymmetries. Lab Chip 11:3774–3784

    Article  Google Scholar 

  • Glawdel T, Elbuken C, Ren C (2012) Droplet formation in microfluidic T-junction generators operating in the transitional regime. I. Experimental observations. Phys Rev E 85:016322

    Article  Google Scholar 

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

    Article  Google Scholar 

  • Guo MT, Rotem A, Heyman JA, Weitz DA (2012) Droplet microfluidics for high-throughput biological assays. Lab Chip 12:2146–2155

    Article  Google Scholar 

  • He M, Edgar JS, Jeffries GD, Lorenz RM, Shelby JP, Chiu DT (2005) Selective encapsulation of single cells and subcellular organelles into picoliter- and femtoliter-volume droplets. Anal Chem 77:1539–1544

    Article  Google Scholar 

  • Hung LH, Choi KM, Tseng W, Tan Y, Shea KJ, Lee AP (2006) Alternating droplet generation and controlled dynamic droplet fusion in microfluidic device for CdS nanoparticle synthesis. Lab Chip 6:174–178

    Article  Google Scholar 

  • Isgor PK, Marcali M, Keser M, Elbuken C (2015) Microfluidic droplet content detection using integrated capacitive sensors. Sensor Actuat B Chem 210:669–675

    Article  Google Scholar 

  • Jin BJ, Kim YW, Lee Y, Yoo JY (2010) Droplet merging in a straight microchannel using droplet size or viscosity difference. J Micromech Microeng 20:035003

    Article  Google Scholar 

  • Kaler KVIS, Prakash R (2014) Droplet microfluidics for chip-based diagnostics. Sensors (Basel) 14:23283–23306

    Article  Google Scholar 

  • Lee M, Collins JW, Aubrecht DM, Sperling RA, Solomon L, Ha JW, Yi GR, Weitz DA, Manoharan VN (2014) Synchronized reinjection and coalescence of droplets in microfluidics. Lab Chip 14:509–513

    Article  Google Scholar 

  • Li ZG, Ando K, Yu JQ, Liu AQ, Zhang JB, Ohl CD (2011) Fast on-demand droplet fusion using transient cavitation bubbles. Lab Chip 11:1879–1885

    Article  Google Scholar 

  • Lin BC, Su YC (2008) On-demand liquid-in-liquid droplet metering and fusion utilizing pneumatically actuated membrane valves. J Micromech Microeng 18:115005

    Article  Google Scholar 

  • Link D, Anna S, Weitz D, Stone H (2004) Geometrically mediated breakup of drops in microfluidic devices. Phys Rev Lett 92:54503

    Article  Google Scholar 

  • Liu K, Ding H, Chen Y, Zhao X (2007) Droplet-based synthetic method using microflow focusing and droplet fusion. Microfluid Nanofluid 3:239–243

    Article  Google Scholar 

  • Liu Z, Ou J, Samy R, Glawdel T, Huang T, Ren CL (2008) Side-by-side comparison of disposable microchips with commercial capillary cartridges for application in capillary isoelectric focusing with whole column imaging detection. Lab Chip 8:1738–1741

    Article  Google Scholar 

  • Lorenz RM, Fiorini GS, Jeffries GD, Lim DS, He M, Chiu DT (2008) Simultaneous generation of multiple aqueous droplets in a microfluidic device. Anal Chim Acta 630:124–130

    Article  Google Scholar 

  • Luong T, Nguyen N, Sposito A (2012) Thermocoalescence of microdroplets in a microfluidic chamber. Appl Phys Lett 100:254105

    Article  Google Scholar 

  • Mazutis L, Baret JC, Griffiths AD (2009) A fast and efficient microfluidic system for highly selective one-to-one droplet fusion. Lab Chip 9:2665–2672

    Article  Google Scholar 

  • Miller OJ, El Harrak A, Mangeat T, Baret JC, Frenz L, El Debs B, Mayot E, Samuels ML, Rooney EK, Dieu P, Galvan M, Link DR, Griffiths AD (2012) High-resolution dose-response screening using droplet-based microfluidics. Proc Natl Acad Sci 109:378–383

    Article  Google Scholar 

  • Niu X, Gulati S, Edel JB, deMello AJ (2008) Pillar-induced droplet merging in microfluidic circuits. Lab Chip 8:1837–1841

    Article  Google Scholar 

  • Song H, Tice JD, Ismagilov RF (2003) A microfluidic system for controlling reaction networks in time. Angew Chemie 115:791–796

    Google Scholar 

  • Tabeling P (2014) Recent progress in the physics of microfluidics and related biotechnological applications. Curr Opin Biotech 25:129–134

    Article  Google Scholar 

  • Tan YC, Fisher JS, Lee AI, Cristini V, Lee AP (2004) Design of microfluidic channel geometries for the control of droplet volume, chemical concentration, and sorting. Lab Chip 4:292–298

    Article  Google Scholar 

  • Tan YC, Ho YL, Lee AP (2007) Droplet coalescence by geometrically mediated flow in microfluidic channels. Microfluid Nanofluid 3:495–499

    Article  Google Scholar 

  • Trivedi V, Doshi A, Kurup GK, Ereifej E, Vandevord PJ, Basu AS (2010) A modular approach for the generation, storage, mixing, and detection of droplet libraries for high throughput screening. Lab Chip 10:2433–2442

    Article  Google Scholar 

  • van Steijn V, Kleijn CR, Kreutzer MT (2010) Predictive model for the size of bubbles and droplets created in microfluidic T-junctions. Lab Chip 10:2513–2518

    Article  Google Scholar 

  • Venkatachalam C, Weidenhof B, Krämer M, Maier WF, Herminghaus S, Seemann R (2010) Optimized droplet-based microfluidics scheme for sol–gel reactions. Lab Chip 10:1700–1705

    Article  Google Scholar 

  • Wheeler AR, Throndset WR, Whelan RJ, Leach AM, Zare RN, Liao YH, Farrell K, Manger ID, Daridon A (2003) Microfluidic device for single-cell analysis. Anal Chem 75:3581–3586

    Article  Google Scholar 

  • White FM (1991) Viscous fluid flow, 2nd edn. McGraw-Hill, New York

    Google Scholar 

  • Xiong B, Ren K, Shu Y, Chen Y, Shen B, Wu H (2014) Recent developments in microfluidics for cell studies. Adv Mater 26:5525–5532

    Article  Google Scholar 

  • Xu L, Lee H, Panchapakesan R, Oh KW (2012) Fusion and sorting of two parallel trains of droplets using a railroad-like channel network and guiding tracks. Lab Chip 12:3936–3942

    Article  Google Scholar 

  • Yang L, Wang K, Tan J, Lu Y, Luo G (2011) Experimental study of microbubble coalescence in a T-junction microfluidic device. Microfluid Nanofluid 12:715–722

    Article  Google Scholar 

  • Yoon DH, Jamshaid A, Ito J, Nakahara A, Tanaka D, Akitsu T, Sekiguchi T, Shoji S (2014) Active microdroplet merging by hydrodynamic flow control using a pneumatic actuator-assisted pillar structure. Lab Chip 14:3050–3055

    Article  Google Scholar 

Download references

Acknowledgements

The authors gratefully acknowledge the support from Canada Natural Sciences and Engineering Council of Canada, Canada Foundation for Innovation, Canada Research Chair program and Advanced Electrophoresis Solutions Ltd, through grants to Dr. Carolyn L. Ren. A. Brukson acknowledges the support of Waterloo Institute of Nanotechnology through a fellowship.

Author information

Authors and Affiliations

  1. Department of Mechanical and Mechatronics Engineering, University of Waterloo, 200 University Ave W., Waterloo, ON, N2L 3G1, Canada

    Xiaoming Chen, Alexander Brukson & Carolyn L. Ren

Authors
  1. Xiaoming Chen
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Alexander Brukson
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Carolyn L. Ren
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Carolyn L. Ren.

Additional information

This article is part of the topical collection “2016 International Conference of Microfluidics, Nanofluidics and Lab-on-a-Chip, Dalian, China” guest edited by Chun Yang, Carolyn Ren and Xiangchun Xuan.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (AVI 3811 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Chen, X., Brukson, A. & Ren, C.L. A simple droplet merger design for controlled reaction volumes. Microfluid Nanofluid 21, 34 (2017). https://doi.org/10.1007/s10404-017-1875-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s10404-017-1875-x

Keywords

Search

Navigation