화학공학소재연구정보센터
Korea-Australia Rheology Journal, Vol.19, No.3, 157-164, November, 2007
Spherical and cylindrical microencapsulation of living cells using microfluidic devices
E-mail:
Microencapsulation of cells within microfluidic devices enables explicit control of the membrane thickness or cell density, resulting in improved viability of the transplanted cells within an aggressive immune system. In this study, living cells (3T3 and L929 fibroblast cells) are encapsulated within a semi-permeable membrane (calcium crosslinked alginate gel) in two different device designs, a flow focusing and a core-annular flow focusing geometry. These two device designs produce a bead and a long microfibre, respectively. For the alginate bead, an alginate aqueous solution incorporating cells flows through a flow focusing channel and an alginate droplet is formed from the balance of interfacial forces and viscous drag forces resulting from the continuous (oil) phase flowing past the alginate solution. It immediately reacts with an adjacent CaCl2 drop that is extruded into the main flow channel by another flow focusing channel downstream of the site of alginate drop creation. Depending on the flow conditions, monodisperse microbeads of sizes ranging from 50-200 μm can be produced. In the case of the microfibre, the alginate solution with cells is extruded into a continuous phase of CaCl2 solution. The diameter of alginate fibres produced via this technique can be tightly controlled by changing both flow rates. Cell viability in both forms of alginate encapsulant was confirmed by a LIVE/DEAD cell assay for periods of up to 24 hours post encapsulation.
  1. Anna SL, Bontoux N, Stone HA, Appl. Phys. Lett., 82(3), 364 (2003)
  2. Chang TMS, Science, 146, 524 (1964)
  3. Fan MY, Lum ZP, Fu XW, Levesque L, Tai IT, Sun AM, Diabetes, 39, 519 (1990)
  4. Hong JS, Cooper-White JJ, Drop formation of a non-Newtonian fluid in a flow-focusing microfluidic channel, in preparation (2007)
  5. Jeong WJ, Kim JY, Kim SJ, Lee SH, Mensing G, Beebe DJ, Lab Chip, 4, 576 (2004)
  6. Jeong WJ, Kim JY, Choo J, Lee EK, Han CS, Beebe DJ, Seong GH, Lee SH, Langmuir, 21(9), 3738 (2005)
  7. Khattak SF, Bhatia SR, Roberts SC, Tissue Eng., 11(5/6), 974 (2005)
  8. Lacy PE, Kostianovsky M, Diabetes, 16, 35 (1967)
  9. Li CH, Microfluidic Lab-on a-chip for chemical and biological analysis and discovery, CRC press (2006)
  10. Lim F, Sun AM, Science, 210, 908 (1980)
  11. Microprobes, Product information MP07013, LIVE/DEAD Reduced Biohazard Viability/Cytotoxicity Kit#1 (L-7013)
  12. Microprobes, Product information MP03224, LIVE/DEAD Viability/ Cytotoxicity Kit for mammalian cells
  13. Rayleigh L, Proc. R. SoC., 29, 71 (1879)
  14. Strand BL, Cell Transplant, 10, 263 (2001)
  15. Sun YL, Ma XJ, Zhou DB, Vacek I, Sun AM, J. Clin. Invest., 98, 1417 (1996)
  16. Sugiura S, Oda T, Izumida Y, Aoyagi Y, Satake M, Ochiai A, Ohkohchi N, Nakajima M, Biomaterials, 26, 3327 (2005)
  17. Utada AS, Lorenceau E, Link DR, Kaplan PD, Stone HA, Weitz DA, Science, 308, 537 (2005)
  18. Xu Q, Appl. Phys. Lett., 85(17), 3726 (2004)