화학공학소재연구정보센터
Macromolecular Research, Vol.26, No.12, 1143-1149, December, 2018
Interfacial Compression-Dependent Merging of Two Miscible Microdroplets in an Asymmetric Cross-Junction for In Situ Microgel Formation
E-mail:,
Controlling the merging of different microdroplets in a microfluidics system could generate a multitude of complex droplets because of their inherent surface tension, but poses a significant challenge because of their high surface tension. Here, a novel microfluidic merging technique is introduced using an asymmetric cross-junction geometry which increases the interfacial compression between two microdroplets. Microdroplets of two viscous polymer solutions, oxidized dextran (ODX) and N-carboxyethyl chitosan (N-CEC), which can undergo a crosslinking reaction via Schiff base formation, are allowed to merge at the asymmetric cross-junction without the assistance of additional merging schemes. The N-CEC and ODX microdroplets being formed at their orifices contact at a more favorable position to overcome their interfacial tension through this asymmetric geometry, until the interfacial layer breaks and pushes the former (with higher viscosity) into the latter. On the other hand, a typical symmetric cross-junction geometry cannot induce merging, because of insufficient interfacial compression generated by direct collision between two droplets. The merged N-CEC and ODX droplets soon become completely homogeneous via diffusion, ultimately leading to in situ microgel formation. Changing the concentration of ODX further controls the crosslinking density of the microgels. In addition, the viability of cells encapsulated within the microgels is well maintained, demonstrating the biocompatibility of the entire process. Taken together, the microfluidic merging technique introduced here could be broadly applicable for engineering cell-encapsulated microgels for biomedical applications.
  1. Thorsen T, Roberts RW, Arnold FH, Quake SR, Phys. Rev. Lett., 86, 4163 (2001)
  2. Cramer C, Fischer P, Windhab EJ, Chem. Eng. Sci., 59(15), 3045 (2004)
  3. Anna SL, Bontoux N, Stone HA, Appl. Phys. Lett., 82, 364 (2003)
  4. Nabavi SA, Vladisavljevic GT, Manovic V, Chem. Eng. J., 322, 140 (2017)
  5. Chan HF, Ma S, Tian J, Leong KW, Nanoscale, 9, 3485 (2017)
  6. Tyowua AT, Yiase SG, Binks BP, J. Colloid Interface Sci., 488, 127 (2017)
  7. Zhang Q, Savagatrup S, Kaplonek P, Seeberger PH, Swager TM, ACS Cent. Sci., 3, 309 (2017)
  8. Seiffert S, Romanowsky MB, Weitz DA, Langmuir, 26(18), 14842 (2010)
  9. Teh SY, Lin R, Hung LH, Lee AP, Lab Chip, 8, 198 (2008)
  10. Sun M, Bithi SS, Vanapalli SA, Lab Chip, 11, 3949 (2011)
  11. Tan YC, Ho YL, Lee AP, Microfluid. Nanofluid., 3, 495 (2007)
  12. Yang CH, Lin YS, Huang KS, Huang YC, Wang EC, Jhong JY, Kuo CY, Lab Chip, 9, 145 (2009)
  13. Liu K, Ding HJ, Chen Y, Zhao XZ, Microfluid. Nanofluid., 3, 239 (2007)
  14. Bremond N, Thiam AR, Bibette J, Phys. Rev. Lett., 100, 024501 (2008)
  15. Lin BC, Su YC, J. Micromech. Microeng., 18, 115005 (2008)
  16. Link DR, Anna SL, Weitz DA, Stone HA, Phys. Rev. Lett., 92, 054503 (2004)
  17. Tan YC, Fisher JS, Lee AI, Cristini V, Lee AP, Lab Chip, 4, 292 (2004)
  18. Sato H, Matsumura H, Keino S, Shoji S, J. Micromech. Microeng., 16, 2318 (2006)
  19. Ziaie B, Baldi A, Lei M, Gu Y, Siegel RA, Adv. Drug Deliv. Rev., 56, 145 (2004)
  20. Kim S, Oh J, Cha C, Colloids Surf. B: Biointerfaces, 147, 1 (2016)
  21. Gach PC, Iwai K, Kim PW, Hillson NJ, Singh AK, Lab Chip, 17, 3388 (2017)
  22. Um E, Park JK, Lab Chip, 9, 207 (2009)
  23. Christopher GF, Bergstein J, End NB, Poon M, Nguyen C, Anna SL, Lab Chip, 9, 1102 (2009)
  24. Tan YC, Ho YL, Lee AP, Microfluid. Nanofluid., 3, 495 (2007)
  25. Okushima S, Nisisako T, Torii T, Higuchi T, Langmuir, 20(23), 9905 (2004)
  26. Chu LY, Utada AS, Shah RK, Kim JW, Weitz DA, Angew. Chem.-Int. Edit., 46, 8970 (2007)
  27. Chokkalingam V, Weidenhof B, Kramer M, Herminghaus S, Seemann R, Maier WF, ChemphysChem, 11, 2091 (2010)
  28. Chokkalingam V, Weidenhof B, Kramer M, Maier WF, Herminghaus S, Seemann R, Lab Chip, 10, 1700 (2010)
  29. Jin BJ, Kim YW, Lee Y, Yoo JY, J. Micromech. Microeng., 20, 035003 (2010)
  30. Fidalgo LM, Abell C, Huck WT, Lab Chip, 7, 984 (2007)
  31. Niu X, Gulati S, Edel JB, deMello AJ, Lab Chip, 8, 1837 (2008)
  32. Sivasamy J, Chim YC, Wong TN, Nguyen NT, Yobas L, Microfluid. Nanofluid., 8, 409 (2010)
  33. Gu H, Duits MHG, Mugele F, Int. J. Mol. Sci., 12(4), 2572 (2011)
  34. Lee M, Collins JW, Aubrecht DM, Sperling RA, Solomon L, Ha JW, Yi GR, Weitz DA, ManoharanVN, Lab Chip, 14, 509 (2014)
  35. Zagnoni M, Cooper JM, Lab Chip, 9, 2652 (2009)
  36. Guzman AR, Kim HS, de Figueiredo P, Han A, Biomed. Microdevices, 17, 35 (2015)
  37. Varma VB, Ray A, Wang ZM, Wang ZP, Ramanujan RV, Sci. Rep., 6, 37671 (2016)
  38. Jung J, Kim K, Choi SC, Oh J, Biotechnol. Lett., 36(7), 1549 (2014)
  39. Weng L, Romanov A, Rooney J, Chen W, Biomaterials, 29, 3905 (2008)
  40. Jung J, Oh J, Biomicrofluidics, 8, 036503 (2014)
  41. Oh J, Kim K, Choi S, Jung J, Dig. J. Nanomater. Biostruct., 9, 739 (2014)
  42. Tice JD, Song H, Lyon AD, Ismagilov RF, Langmuir, 19(22), 9127 (2003)
  43. Berry JD, Neeson MJ, Dagastine RR, Chan DYC, Tabor RF, J. Colloid Interface Sci., 454, 226 (2015)
  44. Fordham S, Proc. Royal Soc. A, 194, 1 (1948)