This work describes a novel microfluidic method to generate uniform water-in-oil (W/O) microspheres using the phase separation technique. Axiomatic design theory (ADT) was employed for the conceptual design of microchannel systems, and ADT verified that the proposed microfluidic system is a decoupled design. The integration of hydrodynamic flow focusing method and crossflow method is realized in a microfluidic device with oil phase and aqueous phase. The immiscible fluids are fed by continuous air pressure. By the hydrodynamic flow focusing method, the width of the dispersed focused aqueous phase is controlled. The focused flow enters T-junction geometry downstream, and the crossflow interferes with the focused flow. By varying the applied pressure to the crossflow, the W/O microspheres are formed at the T-junction. Based on this approach, the size of the W/O microspheres can be successfully controlled from 16 μm to 35 μm in diameter within about 5% of variation. The present method has advantages such as good sphericity, few satellite droplets, active control of the microsphere diameter, and high throughput with the simple and low cost process. To achieve the promising results, this integrating method reveals high potential for production of polymer based microspheres.

References

References
1.
Joscelyne
,
S. M.
, and
Tragardh
,
G.
,
2000
, “
Membrane Emulsification—A Literature Review
,”
J. Membr. Sci.
,
169
(
1
),
pp.
107
117
.10.1016/S0376-7388(99)00334-8
2.
Freitas
,
S.
,
Merkle
,
H. P.
, and
Gander
,
B.
,
2005
, “
Microencapsulation by Solvent Extraction/Evaporation: Reviewing the State of the Art of Microsphere Preparation Process Technology
,”
J. Controlled Release
,
102
,
pp.
313
332
.10.1016/j.jconrel.2004.10.015
3.
Kawakatsu
,
T.
,
Kikuchi
,
Y.
, and
Nakajima
,
M.
,
1997
, “
Regular-Sized Cell Creation in Microchannel Emulsification by Visual Microprocessing Method
,”
J. Am. Oil Chem. Soc.
,
74
(
3
),
pp.
317
321
.10.1007/s11746-997-0143-8
4.
Dendukuri
,
D.
,
Tsoi
,
K.
,
Hatton
,
T. A.
, and
Doyle
,
P. S.
,
2005
, “
Controlled Synthesis of Nonspherical Microparticles Using Microfluidics
,”
Langmuir
,
21
(
6
),
pp.
2113
2116
.10.1021/la047368k
5.
Nisisako
,
T.
,
Torii
,
T.
, and
Higuchi
,
T.
,
2002
, “
Droplet Formation in a Microchannel Network
,”
Lab Chip
,
2
(
1
),
pp.
24
26
.10.1039/b108740c
6.
Guillot
,
P.
, and
Colin
,
A.
,
2005
, “
Stability of Parallel Flows in a Microchannel After a T Junction
,”
Phys. Rev. E
,
72
(
6
), p.
066301
.10.1103/PhysRevE.72.066301
7.
Thorsen
,
T.
,
Maerkl
,
S. J.
, and
Quake
,
S. R.
,
2002
, “
Microfluidic Large-Scale Integration
,”
Science
,
298
(
5593
),
pp.
580
584
.10.1126/science.1076996
8.
Bokenkamp
,
D.
,
Desai
,
A.
,
Yang
,
X.
,
Tai
,
Y. C.
,
Marzluff
,
E. M.
, and
Mayo
,
S. L.
,
1998
, “
Microfabricated Silicon Mixers for Submillisecond Quench-Flow Analysis
,”
Anal. Chem.
,
70
(
2
),
pp.
232
236
.10.1021/ac9708250
9.
Thorsen
,
T.
,
Roberts
,
R. W.
,
Arnold
,
F. H.
, and
Quake
,
S. R.
,
2001
, “
Dynamic Pattern Formation in a Vesicle-Generating Microfluidic Device
,”
Phys. Rev. Lett.
,
86
(
18
),
pp.
4163
4166
.10.1103/PhysRevLett.86.4163
10.
Kawakatsu
,
T.
,
Boom
,
R. M.
,
Nabetani
,
H.
,
Kikuchi
,
Y.
, and
Nakajima
,
M.
,
1999
, “
Emulsion Breakdown: Mechanisms and Development of Multilayer Membrane
,”
AIChE J.
,
45
(
5
),
pp.
967
975
.10.1002/aic.690450507
11.
Kobayashi
,
I.
,
Nakajima
,
M.
,
Chun
,
K.
,
Kikuchi
,
Y.
, and
Fukita
,
H.
,
2002
, “
Silicon Array of Elongated Through-Holes for Monodisperse Emulsion Droplets
,”
AIChE J.
,
48
(
8
),
pp.
1639
1644
.10.1002/aic.690480807
12.
Song
,
K.-Y.
,
Chiao
,
M.
,
Stoeber
,
B.
,
Hafeli
,
U.
,
Gupta
,
M. M.
, and
Zhang
,
W. J.
,
2009
, “
Formation of Uniform Microspheres Using a Perforated Silicon Membrane: A Preliminary Study
,”
J. Med. Devices
,
3
(
3
), p.
034503
.10.1115/1.3212556
13.
Tice
,
J. D.
,
Lyon
,
A. D.
, and
Ismagilov
,
R. F.
,
2004
, “
Effects of Viscosity on Droplet Formation and Mixing in Microfluidic Channels
,”
Anal. Chim. Acta
,
507
(
1
),
pp.
73
77
.10.1016/j.aca.2003.11.024
14.
Tice
,
J. D.
,
Song
,
H.
,
Lyon
,
A. D.
, and
Ismagilov
,
R. F.
,
2003
, “
Formation of Droplets and Mixing in Multiphase Microfluidics at Low Values of the Reynolds and the Capillary Numbers
,”
Langmuir
,
19
(
22
),
pp.
9127
9133
.10.1021/la030090w
15.
Van Der Graaf
,
S.
,
Nisisako
,
T.
,
Schroen
,
C. G. P. H.
,
Van Der Sman
,
R. G. M.
, and
Boom
,
R. M.
,
2006
, “
Lattice Boltzmann Simulations of Droplet Formation in a T-Shaped Microchannel
,”
Langmuir
,
22
(
9
),
pp.
4144
4152
.10.1021/la052682f
16.
Van Der Graaf
,
S.
,
Steegmans
,
M. L. J.
,
Van Der Sman
,
R. G. M.
,
Schroen
,
C. G. P. H.
, and
Boom
,
R. M.
,
2005
, “
Droplet Formation in a T-Shaped Microchannel Junction: A Model System for Membrane Emulsification
,”
Colloids Surf., A
,
266
(
1–3
),
pp.
106
116
.10.1016/j.colsurfa.2005.06.019
17.
Shan
,
X. W.
, and
Chen
,
H. D.
,
1993
, “
Lattice Boltzmann Model for Simulating Flows With Multiple Phases and Components
,”
Phys. Rev. E
,
47
(
3
),
pp.
1815
1819
.10.1103/PhysRevE.47.1815
18.
Swift
,
M. R.
,
Orlandini
,
E.
,
Osborn
,
W. R.
, and
Yeomans
,
J. M.
,
1996
, “
Lattice Boltzmann Simulations of Liquid-Gas and Binary Fluid Systems
,”
Phys. Rev. E
,
54
(
5
),
pp.
5041
5052
.10.1103/PhysRevE.54.5041
19.
Ganan-Calvo
,
A. M.
,
1998
, “
Generation of Steady Liquid Microthreads and Micron-Sized Monodisperse Sprays in Gas Streams
,”
Phys. Rev. Lett.
,
80
(
2
),
pp.
285
288
.10.1103/PhysRevLett.80.285
20.
Ganan-Calvo
,
A. M.
, and
Barrero
,
A.
,
1999
, “
A Novel Pneumatic Technique to Generate Steady Capillary Microjets
,”
J. Aerosol Sci.
,
30
(
1
),
pp.
117
125
.10.1016/S0021-8502(98)00029-9
21.
Knight
,
J. B.
,
Vishwanath
,
A.
,
Brody
,
J. P.
, and
Austin
,
R. H.
,
1998
, “
Hydrodynamic Focusing on a Silicon Chip: Mixing Nanoliters in Microseconds
,”
Phys. Rev. Lett.
,
80
(
17
),
pp.
3863
3866
.10.1103/PhysRevLett.80.3863
22.
Kenis
,
P. J. A.
,
Ismagilov
,
R. F.
, and
Whitesides
,
G. M.
,
1999
, “
Microfabrication Inside Capillaries Using Multiphase Laminar Flow Patterning
,”
Science
,
285
(
5424
),
pp.
83
85
.10.1126/science.285.5424.83
23.
Anna
,
S. L.
,
Bontoux
,
N.
, and
Stone
,
H. A.
,
2003
, “
Formation of Dispersions Using “Flow Focusing” in Microchannels
,”
Appl. Phys. Lett.
,
82
(
3
),
pp.
364
366
.10.1063/1.1537519
24.
Suh
,
N. P.
,
1990
,
The Principles of Design
,
Oxford University Press
,
New York
.
25.
Kreith
,
F.
,
2004
,
The CRC Handbook of Mechanical Engineering
(
Handbook Series for Mechanical Engineering
),
CRC Press
,
Boca Raton, FL
.
26.
Song
,
K.-Y.
,
Zhang
,
W.
, and
Gupta
,
M.
,
2011
, “
Incorporation of Axiomatic Design Theory Into Design of a Microchannel System for Uniform and Size-Controllable Microspheres
,”
Int. J. Adv. Manuf. Technol.
,
57
,
pp.
491
499
.10.1007/s00170-011-3324-4
27.
Melamed
,
M. R.
,
Lindmo
,
T.
, and
Mendelsohn
,
M. L.
,
1994
,
Flow Cytometry and Sorting
,
Wiley-Liss
,
New York
.
28.
Kobayashi
,
I.
, and
Nakajima
,
M.
,
2002
, “
Effect of Emulsifiers on the Preparation of Food-Grade Oil-in-Water Emulsions Using a Straight-Through Extrusion Filter
,”
Eur. J. Lipid Sci. Technol.
,
104
(
11
),
pp.
720
727
.10.1002/1438-9312(200211)104:11<720::AID-EJLT720>3.0.CO;2-E
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