在藥物使用的範疇中，如果想要使藥品能夠完全的發揮出療效，藥物的控制與釋放一向是研究的重點；並且在過去的研究文獻中發現，藥物載體的粒徑越均一，則在應用於藥物的控制與釋放上就越有優勢，但在過去文獻中所提出的製作方式，均無法有效獲得均一粒徑的載體。本研究設計了三組流道形狀和利用翻模技術製作PDMS微流道晶片，用於生成均一粒徑乳化球，在研究中設計了十字型、T字型 (type 1和type 2)三種不同微流道晶片，希望可以生成均一粒徑的乳化球，並應用於生成均一粒徑光交聯微粒子的製備上。本研究成功利用所設計的PDMS微流道晶片設備，生成均一粒徑乳化球，並且應用在光交聯微粒子上，並且探討了分離相與連續相的流量改變與生成之乳化球大小之關係，粒徑分布大小在40 ~1000 µm之間。由實驗結果中發現，當固定分離相流量時，越大的連續相流量，將得以生成越小的乳化球；相對地，在固定連續相流量的情形下，當分離相的流量越小，所生成的乳化球尺寸也越小。

In this paper the manipulation of UV-polymerizable microparticles, using a microfluidic chip, for the encapsulation of gold nanoparticles is presented. Our strategy is based on hydrodynamic-focusing on the forming of a series of self-assembling sphere structures, the so-called water-in-oil (W/O) emulsions, in the cross-junction microchannel and T-junction microchannel. We have demonstrated that one can control the size of UV-polymerizable microparticles from 40 µm to 1000 µm in diameter (with a variation less than 10%) by altering the relative sheath/sample flow rate ratio. The microfluidic chip is capable of generating relatively uniform micro-droplets and has the advantages of active control of droplet diameter, simple and low cost process, and high throughput.

[1] L. G. Griffith, “Polymeric biomaterials,” Acta Materialia, 48, 263, 2000.
[2] http://www.chemnet.com.tw/magazine/200306/index7.htm
[3] J. L. Hill-West, S. M. Chowdhury, R. C. Dunn and J. A. Hubbell, “Efficacy of a resorbable hydrogel barrier, oxidized regenerated cellulose, and hyaluronic acid in the prevention of ovarian adhesions in a rabbit model,” Fertility and Sterility , 62, 630, 1994.
[4] S. M. Chowdhury and J. A. Hubbell, “Adhesion prevention with ancord release via a tissue-adherent hydrogel,” Journal of Surgical Research, 61, 58, 1996.
[5] J. Elisseeff, W. McIntosh, K. Anseth, S. Riley, P. Ragan and R. Langer, “Photoencapsulation of chondrocytes in poly(ethylene oxide)-based semi-interpenetrating networks,” Journal of Biomedical Materials Research, 51, 164, 2000.
[6] B. A. M. Venhoven, A. J. Gee and C. L. Davidson, “Light initiation of dental resins: dynamics of the polymerization,” Biomaterials, 17, 2313, 1996.
[7] K. T. Nguyen and J. L. West, “Photopolymerization hydrogels for tissue engineering applications,” Biomaterials, 23, 4307, 2002.
[8] A. B. Scranton, C. N. Bowman and R. W. Peiffer, “Photopolymerization fundamentals and applications,” New Orleans: ACS Publishers, 1996.
[9] C. Decker, “UV-curing chemistry: past, present, and future,” Journal of Coatings Technology, 59, 97, 1987.
[10] J. P. Fisher, D. Dean, P. S. Engel and A. G. Mikos, “Photoinitiated polymerization of biomaterials,” Annual Review of Materials Research, 31, 171, 2000.
[11] S. J. Byrant, C. R. Nuttelman and K. S. Anseth, “Cytocompatibility of UV and visible kight photoinitiating systems on cultured NIH/3T3 fibroblasts in vitro,” Journal of Biomaterials Science, Polymer Edition, 11, 439, 2000.
[12] J. L. West and J. A. Hubbell, “Separation of the arterial wall from blood contact using hydrogel barriers reduces intimal thickening after balloon injuries in the rat: the roles of medial and luminal factors in arterial healing,” Proceedings of the National Academy of Sciences of the United States of America, 93, 13188, 1996.
[13] A. S. Sawhney and C. P. Pathak, “Optimization of photopolymerized bioerodible hydrogel properties for adhesion prevention,” Journal of Biomedical Materials Research, 28, 831, 1994.
[14] J. Lee, C. W. Macosko and D. W. Urry, “Swelling behavior of crosslinked elastomeric polypentapeptide-based hydrogels,” Macromolecule, 34, 4114, 2001.
[15] B. K. Mann, A. S. Gobin, A. T. Tsai, R. H. Schmedlen and J. L. West, “Smooth muscle cell growth in photopolymerized hydrogels with cell adhesive and proteolytically degradable domains: synthetic ECM analogs for tissue engineering,” Biomaterials, 22, 3045, 2001.
[16] D. A. Drew and R. T. Lahey, “Phase distribution mechanisms in two-phase flow in a circular pipe,” Journal of Fluid Mechanics, 117, 91, 1982.
[17] R. T. Lahey and D. A. Drew, “The aanalysis of two-phase flow and heat transfer using a multidimensional, four field, two fluid model,” Nuclear Engineering and Design, 204, 29, 2001.
[18] T. C. Kuo, A. S. Yang and C. C. Chieng, ‘‘Bubble size and system pressure effects on phase distribution for two phase turbulent bubbly flows,’’ Journal of Mechanical Engineering Science, 215, 121, 2001.
[19] M. Ishii, “Thermal-fluid dynamics of two-phase flow,” Eyrolles, Paris, 1975.
[20] M. Ishii and K. Mishima, “Two-fluid model hydrodynamic constitutive relation,” Nuclear Engineering and Design, 82, 107, 1984.
[21] M. Ishii and N.Zuber, “Drag coefficient and relative velocity in bubbly, droplet or particulate flows,” AIChE Journal, 25, 843, 1979.
[22] R. T. Lahey, “The analysis of phase separation and phase distribution phenomena using two-fluid models,” Nuclear Engineering and Design, 122, 17, 1990.
[23] P. J. C. Taylor, “A device for counting small particles suspended in a fluid through a tube,” Nature, 171, 37, 1953.
[24] W. H. Coulter, “High speed automatic blood cell and cell size analyzer,” Proceedings of the National Electronics Conference, 1034, 1956.
[25] K. Seiler, D. J. Harrison and A. Manz, “Planar chips technology for miniaturization and integration of separation techniques into monitoring systems,” Journal of Chromatography, 593, 253, 1992.
[26] F. F. Mandy, M. Bergeron and T. Minkus, “Principles of flow cytometry,” Transfusion Science, 16, 303, 1995.
[27] P. L. Judson and L. L. Van, “Flow cytometry,” Primary Care Update for OB/GYNS, 4, 87, 1997.
[28] B. C. Ferrari, G. Vesey, K. A. Davis, M. Gucci and D. Veal, “A novel two-color flow cytometric assay for the detection of cryptosporidium in environmental water samples,” Cytometry, 41, 216, 2000.
[29] R. Rong, J. W. Choi and C. H. Ahn, “A functional magnetic bead biocell sorter using fully integrated magnetic micro nano tips,” IEEE Micro Electro Mechanical Systems, 530, 2003.
[30] C. B. Fuh, H. Y. Tsai and J. Z. Lai, “Development of magnetic split-flow thin fractionation for continuous particle separation,” Analytica Chimica Acta, 497, 115, 2003.
[31] M. Ozkan, M. Wang, C. Ozkan, R. Flynn, A. Birkbeck and S. Esener, “Optical manipulation of objects and biological cells in microfluidic devices,” Biomedical Microdevices, 5, 61, 2003.
[32] I. Doh and Y. H. Cho, “A continuous cell separation chip using hydrodynamic dielectrophoresis process,” Sensors and Actuators A, 121, 59, 2005.
[33] F. Arai, A. Ichikawa, M. Ogawa, T. Fukuda, K. Horio and K. Itoigawa, “High-speed separation system of randomly suspended single living cells by laser trap and dielectrophoresis,” Electrophoresis, 22, 283, 2001.
[34] X. B. Wang, J. Vykoukal, F. F. Becker and P. R. C. Gascoyne, “Separation of polystyrene microbeads using dielectrophoretic/gravitational field-flow-fractionation,” Biophysical Journal, 74, 2689, 1998.
[35] Y. C. Tan, J. S. Fisher, A. I. Lee, V. Cristiniab and A. P. Lee, “Design of microfluidic channel geometries for the control of droplet volume, chemical concentration, and sorting,” Lab On a Chip, 4, 292, 2004.
[36] Y. C. Tan and A. P. Lee, “Microfluidic separation of satellite droplets as the basis of a monodispersed micron and submicron emulsification system,” Lab On a Chip, 5, 1178, 2005.
[37] S. L. Anna, N. Bontoux and H. A. Stone, “Formation of dispersions using “flow focusing” in microchannels,” Applied Physics Letter, 82, 364, 2003.
[38] V. Cristini and Y. C. Tan, “Theory and numerical simulation of droplet dynamics in complex flows-a review,” Lab on a Chip, 4, 257, 2004.
[39] W. J. Jeong, J. Y. Kim, J. Choo, E. K. Lee, C. S. Han, D. J. Beebe, G. H. Seong and S. H. Lee, “Continuous fabrication of biocatalyst immobilized microparticles using photopolymerization and immiscible liquids in microfluidic systems,” Langmuir, 21, 3738, 2005.
[40] T. R. Hsu, “MEMS & Microsystems Design and Manufacture,” McGraw-Hill, Boston, 2002.
[41] D. J. Campbell, K. J. Beckman, C. E. Calderon, P. W. Doolan, R. H. Moore, A. B. Ellis and G. C. Lisensky, “Replication and compression of bulk surface structures with polydimethylsiloxane elastomer,” Journal of Chemical Education, 76, 537, 1999.
[42] D. Armani, C. Liu and N. Aluru, “Re-configurable fluid circuits by PDMS elastomer micromachining,” IEEE Micro Electro Mechanical Systems, 222, 1999.
[43] M. J. Owen and P. J. Smith, “Plasma treatment of polydimethylsiloxane,” Journal of Adhesion Science and Technology, 8, 1063, 1994.