Biotechnology and Bioprocess Engineering

, Volume 6, Issue 4, pp 213–230

Microencapsulation methods for delivery of protein drugs

Article

Abstract

Recent advances in recombinant DNA technology have resulted in development of many new protein drugs. Due to the unique properties of protein drugs, they have to be delivered by parenteral injection. Although delivery of protein drugs by other routes, such as pulmonary and nasal routes, has shown some promises, to date most protein drugs are administered by parenteral routs. For long-term delivery of protein drugs by parenteral administration, they have been developed, and the currently used microencapsulation methods are reviewed here. The microencapsulation methods have been divided based on the method used. They are: solvent evaporation/extraction; phase separation (coacervation); spray drying; ionotropic gelation/polyelectrolyte complexation; interfacial polymerization; and supercritical fluid precipitation. Each method is described for its applications, advantages, and limitations.

Keywords

protein peptide drug delivery microparticle microencapsulation 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [1]
    Thies, C. (1996) A survey of microencapsulation processes. pp. 1–19. In: S. Benita (ed.).Microencapsulation: Methods and Industrial Applications. Marcel Dekker, Inc., New York, USA.Google Scholar
  2. [2]
    Wang, H. T., E. Schmitt, D. R. Flanagan, and R. J. Linhardt (1991) Influence of formulation methods on the in vitro controlld release of protein from poly(ester) microspheres.J. Controlled Release 17: 23–32.Google Scholar
  3. [3]
    Pradhan, R. S. and R. C. Vasavada (1994) Formulation and in vitro release study on poly(DL-lactide) microspheres containing hydrophilic compounds: glycine homopeptides.J. Controlled Release 30: 143–154.Google Scholar
  4. [4]
    Uchida, T., A. Yagi, Y. Oda, and S. Goto (1996) Microencapsulation of ovalbumin in poly(lactide-co-glycolide) by an oil-in-oil (o/o) solvent evaporation method.J. Microencapsulation 13: 509–518.Google Scholar
  5. [5]
    Morita, T., Y. Sakamura, Y. Horikiri, T. Suzuki, and H. Yoshino (2000) Protein encapsulation into bioegradable microspheres by a novel S/O/W emulsion method using poly(ethylene glycol) as a protein micronization adjuvant.J. Controlled Release 69: 435–444.Google Scholar
  6. [6]
    Kawasima, Y., H. Yamamoto, H. Takeuchi, and Y. Kuno (2000) Mucoadhesive DL-lactide/glycolide copolymer nanospheres coated with chitosan to improve oral delivery of lecatonin.Pharm. Develop. Technol. 5: 77–85.Google Scholar
  7. [7]
    Kawashima, Y., H. Yamamoto, H. Takeuchi, S. Fujioka, and T. Hino (1999) Pulmonary delivery of insulin with nebulized DL-lactide/glycolide copolyer (PLGA) nanospheres to prolong hypoglycemic effect.J. Controlled Release 62: 279–287.Google Scholar
  8. [8]
    Ogawa, Y., H. Okada, M. Yamamoto, and T. Shimamoto (1988) In vivo release of leuprolide acetate from microcapsules prepared with polylactic acids or copoly(lactic/glycolic) acids and in vivo degradation of these polymers.Chem. Pharm. Bull. 36: 2576–2581.Google Scholar
  9. [9]
    Okada, H., T. Heya, Y. Ogawa, and T. Shimamoto (1988) One-month release injectable microcapsules of a luteinizing hormone-releasing hormone agonist (leuprolide acetate) for treating experimental endometriosis in rats.J. Pharmacol. Exp. Ther. 244: 744–750.Google Scholar
  10. [10]
    Lu, W. and T. G. Park (1995) Protein release from poly(lactic-co-glycolic acid) microspheres: protein stability problems.PDA J. Pharm. Sci. Technol. 49: 13–19.Google Scholar
  11. [11]
    Igartua, M., R. M. Hernandez, A. Esquisabel, A. R. Gascon, M. B. Calvo, and J. L. Pedraz (1997) Influence of formulation variables on thein-vitro release of albumin from biodegradable microparticulate systems.J. Microencapsulation 14: 349–356.CrossRefGoogle Scholar
  12. [12]
    Cleland, J. L., A. Mac, B. Boyd, J. Yang, E. T. Duenas, D. Yeung, D. Brooks, C. Hsu, H. Chu, V. Mukku, and A. J. S. Jones (1997) The stability of recombinant human growth hormone in poly(lactic-co-glycolic acid) (PLGA) microspheres.Pharm. Res. 14: 420–425.Google Scholar
  13. [13]
    Sturesson, C. and J. Carlfos (2000) Incorporation of protein in PLG-microspheres with retention of bioactivity.J. Controlled Release 67: 171–178.Google Scholar
  14. [14]
    Morlock, M., H. Koll, G. Winter, and T. Kissel (1997) Microencapsulation of rh-erythropoietin, using biodegradable poly(D,L-lactide-co-glycolide): protein stability and the effects of stabilizing excipients.Eur. J. Pharm. Biopharm. 43: 29–36.Google Scholar
  15. [15]
    Bezemer, J. M., R. Radersma, D. W. Grijpma, P. J. Dijkstra, C. A. van Blitterswijk, and J. Feijen (2000) Microspheres for protein delivery prepared from amphiphilic multiblock copolymers. 1. Influence of preparation techniques on particle characteristics and protein delivery.J. Controlled Release 67: 233–248.Google Scholar
  16. [16]
    Bezemer, J. M., R. Radersma, D. W. Grijpma, P. J. Dijkstra, C. A. van Blitterswijk, and J. Feijen (2000) Microspheres for protein delivery prepared from amphiphilic multiblock copolymers. 2. Modulation of release rate.J. Controlled Release 67: 249–260.Google Scholar
  17. [17]
    Morlock, M., T. Kissel, Y. X. Li, H. Koll, and G. Winter (1998) Erythropoietin loaded microspheres prepared from biodegradable LPLG-PEO-LPLG triblock copolymers: protein stabilization and in-vitro release properties.J. Controlled Release 56: 105–115.Google Scholar
  18. [18]
    Sah, H. (1999) Stabilization of proteins against methylene chloride/water interface-induced denaturation and aggregation.J. Controlled Release 58: 143–151.Google Scholar
  19. [19]
    Gombotz, W. R., M. S. Healy, and L. R. Brown (1991) Very low temperature casting of controlled release microspheres,US Patent 5,019,400.Google Scholar
  20. [20]
    Ting, T., I. Gonda, and E. M. Gripps (1992) Microparticles of PVA for nasal delivery. I. Generation by spray-drying and spray-desolvation.Pharm. Res. 9: 1330–1335.Google Scholar
  21. [21]
    Sam, A. P., F. D. Haan, and C. Dirix (1994) A novel process for manufacturing PLG microparticles by spray desolvation avoiding the use of toxic solvents.Proc. Int. Symp. Controlled Release Bioact. Mater., June 27–30. Nice, France.Google Scholar
  22. [22]
    Tracy, M. A. (1998) Development and scale-up of a microsphere protein delivery system.Biotechnol. Prog. 14: 108–115.Google Scholar
  23. [23]
    Johnson, O. L., J. L. Cleland, H. J. Lee, M. Charnis, E. Duenas, W. Jaworowicz, D. Shepard, A. Shahzamani, A. J. Jones, and S. D. Putney (1996) A month-long effect from a single injection of microencapsulated human growth hormone.Nat. Med. 2: 795–799.Google Scholar
  24. [24]
    Johnson, O. L., W. Jaworowicz, J. L. Cleland, L. Bailey, M. Charnis, E. Duenas, C. Wu, D. Shepard, S. Magil, T. Last, A. J. S. Jones, and S. D. Putney (1997) The stabilization and encapsulation of human growth hormone into biodegradable microspheres.Pharm. Res. 14: 730–735.Google Scholar
  25. [25]
    Cleland, J. L., O. L. Johnson, S. Putney, and A. J. S. Jones (1997) Recombinant human growth hormone poly-(lactic-co-glycolic acid) microsphere formulation development.Adv. Drug Delivery Rev. 28: 71–84.Google Scholar
  26. [26]
    Lee, H. J., G. Riley, O. Johnson, J. L. Cleland, N. Kim, M. Charnis, L. Bailey, E. Duenas, A. Shahzamani, M. Marian, A. J. Jones, and S. D. Putney (1997)In vivo characterization of sustained-release formulations of human growth hormone.J. Pharmacol. Exp. Ther. 281: 1431–1439.Google Scholar
  27. [27]
    Johnson, O. L. and M. A. Tracy (1999) Peptide and protein drug delivery. pp. 816–833. In: E. Mathiowitz (ed.).Encyclopedia of Controlled Drug Delivery. Jone Wiley & Sons Inc., New York, USA.Google Scholar
  28. [28]
    Nihant, N., S. Stassen, C. Grandfils, R. Jerome, and P. Teyssie (1994) Microencapsulation by coacervation of PLGA: III. Characterization of the final microspheres.Polym. Int. 34: 289–299.Google Scholar
  29. [29]
    Kas, H. S. and L. Oner (2000) Microencapsulation using coacervation. pp. 301–328. In: D. L. Wise (ed.),Handbook of Pharmaceutical Controlled Release Technology. Marcel Dekker, Inc., New York, USA.Google Scholar
  30. [30]
    Burgess, D. J. and A. J. Hickey (1994) Microsphere technology and applications. pp. 1–29. In: J. Swarbrick and J. C. Boylan (eds.).Encyclopedia of Pharmaceutical Technology. Marcel Dekker, Inc., New York, USA.Google Scholar
  31. [31]
    Wu, W. S. (1995) Preparation, characterization, and drug delivery applications of microspheres based on biodegradable lactic/glycolic acid polymers. pp. 1151–1200. In: D. L. Wise (ed.).Encyclopedic Handbook of Biomaterials and Bioengineering. Marcel Dekker, New York, USA.Google Scholar
  32. [32]
    Bakan, J. A. (1986) Microencapsulation. pp. 412–429. In: L. Lachman H. A. Lieberman, and J. L. Kanig (eds.).The Theory and Practice of Industrial Pharmacy. Lea & Febiger, Philadelphia, USA.Google Scholar
  33. [33]
    Sanders, L. M., J. S. Kent, G. I. McRae, B. H. Vickery, T. R. Tice, and D. H. Lewis (1984) Controlled release of LHRH analogue from PLGA microspheres.J. Pharm. Sci. 73: 1294–1297.Google Scholar
  34. [34]
    Ruiz, J. M., B. Tissier, and J. P. Bencit (1989) Microencapsulation of peptide: a study of the phase separation of PLGA copolymers 50/50 by silicone oil.Int. J. Pharm. 49: 69–77.Google Scholar
  35. [35]
    Ruiz, J. M. and J. P. Benoit (1991) In vivo peptide release from PLGA copolymer 50/50 microspheres.J. Controlled Release 16: 177–186.Google Scholar
  36. [36]
    Stassen, S., N. Nihant, V. Martin, C. Grandfils, R. Jerome, and R. Teyssie (1994) Microencapsulation by coacervation of PLGA: 1. Physicochemical characeristics of the phase separation process.Polymer 35: 777–785.Google Scholar
  37. [37]
    Nihant, N., C. Grandfils, R. Jerome, and P. Teyssie (1995) Microencapsulation by coacervation of PLGA: IV. Effect of the processing parameters on coacervation and encapsulation.J. Controlled Release 35: 117–125.Google Scholar
  38. [38]
    Thomasin, C., P. Johansen, R. Alder, R. Bemsel, G. Hottinger, H. Altorfer, A. D. Wright, G. Wehrli, H. P. Merkle, and B. Gander (1996) A contribution to over-coming the problem of residual solvents in biodegradable microspheres prepared by coacervation.Eur. J. Pharm. Biopharm. 42: 16–24.Google Scholar
  39. [39]
    Thomasin, C., G. Corradin, M. Ying, H. P. Merkle, and B. Gander (1996) Tetanus toxoid and synthetic malaria antigen containing poly(lactide)/poly(lactide-co-gly-colide) microspheres: Importance of polymer degradation and antigen release for immune response.J. Controlled Release 41: 131–145.Google Scholar
  40. [40]
    Li, J. K., N. Wang, and X. S. Wu (1997) A novel biodegradable system based on gelatin nanoparticles and poly(lactic-co-glycolic acid) microspheres for protein and peptide drug delivery.J. Pharm. Sci. 86: 891–895.Google Scholar
  41. [41]
    Pettit, D. K., J. R. Lawter, W. J. Huang, S. C. Pankey, N. S. Nightlinger, D. H. Lynch, J. A. Schuh, P. J. Morrissey, and W. R. Gombotz (1997) Characterization of poly(glycolide-co-D,l-lactide)/poly(D,l-lactide) microspheres for controlled release of GM-CSF.Pharm. Res. 14: 1422–1430.Google Scholar
  42. [42]
    McGee, J. P., S. S. Davis, and D. T. O'Hagan (1995) Zero order release of protein from PLGA microparticles prepared using a modified phase separation technique.J. Controlled Release 34: 77–86.Google Scholar
  43. [43]
    Wang, N. and X. S. Wu (1998) A novel approach to stabilization of protein drugs in PLGA microspheres using agarose hydrogel.Int. J. Pharm. 166: 1–14.Google Scholar
  44. [44]
    Wang, N., X. S. Wu, and J. K. Li (1999) A heterogeneously structured composite based on poly(lactic-co-glycolic acid) microspheres and poly(vinyl alcohol) hydrogel nanoparticles for long-term protein drug delivery.Pharm. Res. 16: 1430–1435.Google Scholar
  45. [45]
    Andrianov, A. K., J. Chen, and L. G. Payne (1998) Preparation of hydrogel microspheres by coacervation of aqueous polyphosphazene solutions.Biomaterials 19: 109–115.Google Scholar
  46. [46]
    Brown, K. E., K. Leong, C. Huang, R. Dalal, G. D. Green, H. B. Haimes, P. A. Jimenez, and J. Bathon (1998) Gelatin/chondroitin 6-sulfate microspheres for the delivery of therapeutic proteins to the joint.Arthritis Rheum. 41: 2185–2195.Google Scholar
  47. [47]
    Thomasin, C., B. Gander, and H. P. Merkle (1993) Coacervation of biodegradable polyesters for microencapsulation: A physicochemical approach.Proc. Int. Symp. Controlled Release Bioact. Mater., July 25–30. Washington D.C., USA.Google Scholar
  48. [48]
    Takada, S., Y. Uda, H. Toguchi, and Y. Ogawa (1995) Application of a spray drying technique in the production of TRH-containing injectable sustained-release microparticles of biodegradable polymers.PDA J. Pharm. Sci. Technol. 49: 180–184.Google Scholar
  49. [49]
    FDA (1999) Guidance for industry; Impurities: Residual solvents; VICH GL18.Google Scholar
  50. [50]
    Jizomoto, H. (1985) Phase separation induced in gelatin-based coacervation systems by addition of water-soluble nonionic polymers. II: Effect of molecular weight.J. Pharm. Sci. 74: 469–472.Google Scholar
  51. [51]
    Jizomoto, H. (1984) Phase separation induced in gelatin-based coacervation systems by addition of water-soluble nonionic polymers: I. Microencapsulation.J. Pharm. Sci. 73: 879–882.Google Scholar
  52. [52]
    Giunchedi, P. and U. Conte (1995) Spray-drying as a preparation method of microparticulate drug delivery systems: an overview.S.T.P. Pharma Sci. 5: 276–290.Google Scholar
  53. [53]
    Pavanetto, E., B. Conti, I. Genta, and P. Giunchedi (1992) Solvent evaporation, solvent extraction and spray drying for polylactide microsphere preparation.Int. J. Pharm. 84: 151–159.Google Scholar
  54. [54]
    Wan, L. S. C., P. W. S. Heng, and C. G. H. Chia (1992) Plasticizers and their effects on microencapsulation process by spray-drying in an aqueous system.J. Microencapsulation 9: 53–62.Google Scholar
  55. [55]
    Steber, W., R. Fishbein, and S. M. Cady (1989) Compositions for parenteral administration and their use.US Patent 4,837,381.Google Scholar
  56. [56]
    Mathiowitz, E., H. Bernstein, S. Giannos, P. Dor, T. Turek, and R. Langer (1992) Polyanhydride microspheres. IV. Morphology and characterization of systems made by spray drying.J. Appl. Polym. Sci. 45: 125–134.Google Scholar
  57. [57]
    Gander, B., E. Wehrli, R. Alder, and H. P. Merkle (1995) Quality improvement of spray-dried, protein-loaded D,L-PLA microspheres by appropriate polymer solvent selection.J. Microencapsulation 12: 83–97.Google Scholar
  58. [58]
    Gander, B., P. Johansen, H. Nam-Tran and H. P. Merkle (1996) Thermodynamic approach to protein microencapsulation into poly(D,l-lactide) by spray drying.Int. J. Pharm. 129: 51–61.Google Scholar
  59. [59]
    Bittner, B., B. Ronneberger, R. Zange, C. Volland, J. M. Anderson, and T. Kissel (1998) Bovine serum albumin loaded poly(lactide-co-glycolide) microspheres: the influence of polymer purity on particle characteristics.J. Microencapsulation 15: 495–514.Google Scholar
  60. [60]
    Burgess, D. J. and S. Ponsart (1998) Beta-glucuronidase activity following complex coacervation and spray drying microencapsulation.J. Microencapsulation 15: 569–579.Google Scholar
  61. [61]
    Witschi, C. and E. Doelker (1998) Influence of the microencapsulation method and peptide loading on PLA and PLGA degradation during in vitro testing.J. Controlled Release 51: 327–341.Google Scholar
  62. [62]
    Bittner, B., M. Morlock, H. Koll, G. Winter, and T. Kissel (1998) Recombinant human erythropoietin (rhEPO) loaded poly(lactide-co-glycolide) microspheres: influence of the encapsulation technique and polymer purity on microsphere characteristics.Eur. J. Pharm. Biopharm. 45: 295–305.Google Scholar
  63. [63]
    Bittner, B. and T. Kissel (1999) Ultrasonic atomization for spray drying: a versatile technique for the preparation of protein loaded biodegradable microspheres.J. Microencapsulation 16: 325–41.Google Scholar
  64. [64]
    Baras, B., M. A. Benoit, and J. Gillard (2000) Parameters influencing the antigen release from spray-dried poly(Dl-lactide) microparticles.Int. J. Pharm. 200: 133–145.Google Scholar
  65. [65]
    Baras, B., M. A. Benoit, and J. Gillard (2000) Influence of various technological parameters on the preparation of spray-dried poly(epsilon-caprolactone) microparticles containing a model antigen.J. Microencapsulation 17: 485–498.Google Scholar
  66. [66]
    Takenaka, H., Y. Kawashima, and S. Y. Lin (1981) Polymorphism of spray-dried microencapsulated sulfamethoxazole with cellulose acetate phthalate and colloidal silica, montmorillonite, or talc.J. Pharm. Sci. 70: 1256–1260.Google Scholar
  67. [67]
    Bodmeier, R. and H. Chen (1988) Preparation of biodegradable polylactide microparticles using a spray-drying technique.J. Pharm. Pharmacol. 40: 754–757.Google Scholar
  68. [68]
    Lim, F. and A. M. Sun (1980) Microencapsulated islets as bioartificial endocrine pancreas.Science 210: 908–910.Google Scholar
  69. [69]
    Dulieu, C., D. Poncelet, and R.J. Neufeld (1999) Encapsulation and immobilization techniques. pp. 3–17. In: W. M. Kuhtreiber, R. P. Lanza, and W. L. Chick (eds.).Cell Encapsulation Technology and Therapeutics. Birkhauser, Boston, USA.Google Scholar
  70. [70]
    Acarturk, E. and S. Takka (1999) Calcium alginate microparticles for oral administration: II. Effect of formulation factors on drug release and drug entrapment efficiency.J. Microencapsulation 16: 291–301.Google Scholar
  71. [71]
    Peters, M. C., B. C. Isenberg, J. A. Rowley, and D. J. Mooney (1998) Release from alginate enhances the biological activity of vascular endothelial growth factor.J. Biomater. Sci. Polym. Ed. 9: 1267–1278.Google Scholar
  72. [72]
    Kikuchi, A., M. Kawabuchi, A. Watanabe, M. Sugihara, Y. Sakurai, and T. Okano (1999) Effect of Ca2+-alginate gel dissolution on release of dextran with different molecular weights.J. Controlled Release 58: 21–28.Google Scholar
  73. [73]
    Thu, B., P. Bruheim, T. Espevik, O. Smidsrod, G. Skjak-Braek, and P. Soon-Shiong (1996) Alginate polycation microcapsules. I. Interaction between alginate and polycation.Biomaterials 17: 1031–1040.Google Scholar
  74. [74]
    Takka, S. and F. Acarturk (1999) Calcium alginate microparticles for oral administration: I. Effect of sodium alginate type on drug release and drug entrapment efficiency.J. Microencapsulation 16: 275–290.Google Scholar
  75. [75]
    Polk, A., B. Amsden, K. D. Yao, T. Peng, and M. F. A. Goosen (1994) Controlled release of albumin from chitosan-alginate microcapsules.J. Pharm. Sci. 83: 178–185.Google Scholar
  76. [76]
    Shiraishi, S., T. Imai, and M. Otagiri (1993) Controlled release of indomethacin by chitosan-polelectrolyte complex: optimization and in vivo/in vitro encapsulation.J. Controlled Release 25: 217–225.Google Scholar
  77. [77]
    Mi, F.-L., S.-S. Shyu, C.-Y. Kuan, S.-T. Lee, K.-T. Lu, and S.-E. Jang (1999) Chitosan-polyelectrolyte complexation for the preparation of gel beads and controlled release of Anticancer drug. I. Effect of phosphorous polyelectrolyte complex and enzymatic hydrolysis of polymer.J. Appl. Polym. Sci. 74: 1868–1879.Google Scholar
  78. [78]
    Fernandez-Urrusuno, R., P. Calvo, C. Remunan-Lopez, J. L. Vila-Jato, and M. J. Alonso (1999) Enhancement of nasal absorption of insulin using chitosan nanoparticles.Pharm. Res. 16: 1576–1581.Google Scholar
  79. [79]
    Calvo, P., C. Remunan-Lopez, J. L. Vila-Jato, and M. J. Alonso (1997) Chitosan and chitosan/enthylene oxide-propylene oxide block copolymer nanoparticles as novel carriers for proteins and vaccines.Pharm. Res. 14: 1431–1436.Google Scholar
  80. [80]
    Calvo, P., C. Remunan-Lopez, J. L. Vila-Jato, and M. J. Alonso (1997) Novel hydrophilic chitosan-polyethylene oxide nanoparticles as protein carriers.J. Appl. Polym. Sci. 63: 125–132.Google Scholar
  81. [81]
    Aydin, Z. and J. Akbuga (1996) Chitosan beads for the delivery of salmon calcitonin: Preparation and release characteristics.Int. J. Pharm. 131: 101–103.Google Scholar
  82. [82]
    Long, D. D. (1996) Chitosan-carboxymethylcellulose hydrogels as supports for cell immobilization.J.M.S.-Pure Appl. Chem. A33: 1875–1884.CrossRefGoogle Scholar
  83. [83]
    Tomida, H., C. Nakamura, and S. Kiryu (1994) A novel method for the preparation of controlled release theophylline capsules coated with a polyelecrolyte complex of kappa-carrageenan and chitosan.Chem. Pharm. Bull. 42: 979–981.Google Scholar
  84. [84]
    Patil, R. T. and T. J. Speaker (2000) Water-based microsphere delivery system for proteins.J. Pharm. Sci. 89: 9–15.Google Scholar
  85. [85]
    Sriamornsak, P. and J. Nunthanid (1998) Calcium pectinate gel beads for controlled release drug delivery: I. Preparation and in vitro release studies.Int. J. Pharm. 160: 207–212.Google Scholar
  86. [86]
    Kedzierewicz, F., C. Lombry, R. Rios, M. Hoffman, and P. Maincent (1999) Effect of the formulation on the in-vitro release of propranolol from gellan beads.Int. J. Pharm. 178: 129–136.Google Scholar
  87. [87]
    Brissova, M., I. Lacik, A. C. Powers, A. V. Anilkumar, and T. Wang (1998) Control and measurement of permeability for design of microcapsule cell delivery system.J. Biomed. Mater. Res. 39: 61–70.Google Scholar
  88. [88]
    Lacik, I., M. Brissova, A. V. Anilkumar, A. C. Powers, and T. Wang (1998) New capsule with tailored properties or the encapsulation of living cells.J. Biomed. Mater. Res. 39: 52–60.Google Scholar
  89. [89]
    Bano, M. C., S. Cohen, K. B. Visscher, H. R. Allcock, and R. Langer (1991) A novel synthetic method for hybridoma cell encapsulation.Biotechnology 9: 468–471.Google Scholar
  90. [90]
    Cohen, S., M. C. Bano, K. B. Visscher, M. Chow, H. R. Allcock, and R. Langer (1990) Ionically cross-linkable polyphosphazene: a novel polymer for microencapsulation.J. Am. Chem. Soc. 112: 7832–7833.Google Scholar
  91. [91]
    Kwok, K. M., M. J. Groves, and D. J. Burgess (1991) Production of 5–15 μm diameter alginate-polylysine microcapsules by an air-atomization technique.Pharm. Res. 8: 341–344.Google Scholar
  92. [92]
    Gharapetian, H., N. A. Davis, and A. M. Sun (1986) Encapsulation of viable cells within polyacrylate membranes.Biotechnol. Bioeng. 28: 1595–1600.Google Scholar
  93. [93]
    Guiseley, K. B. (1989) Chemical and physical properties of algal polysaccharides used for cell immobilization.Enzyme Microb. Technol. 11: 706–716.Google Scholar
  94. [94]
    Lanza, R. R. and W. L. Chick (1997) Transplantation of encapsulated cells and tissues.Surgery 121: 1–9.Google Scholar
  95. [95]
    Bodmeier, R. and O. Paeratakul (1991) A novel multiple-unit sustained release indmethacin-hydroxypropyl methylcellulose delivery system prepared by ionotropic gelation of sodium alginate at elevated temperatures.Carbohydr. Polym. 16: 399–408.Google Scholar
  96. [96]
    Pillay, V. C., M. Dangor, T. Govender, K. R. Moopanar, and N. Hurbans (1998) Inotropic gelation: encapsulation of indomethacin in calcium alginate gel discs.J. Microencapsulation 15: 215–226.Google Scholar
  97. [97]
    Sezer, A. D. and J. Akbuga (1999) Release characteristics of chitosan treated alginate beads: I. Sustained release of a macromolecular drug from chitosan treated alginate beads.J. Microencapsulation 199: 195–203.Google Scholar
  98. [98]
    Hearn, E. and R. J. Neufeld (2000) Poly (methylene coguanidine) coated alginate as an encapsulation matrix for urease.Process Biochem. 35: 1253–1260.Google Scholar
  99. [99]
    Wang, T., I. Lacik, M. Brissova, A. V. Anikumar, A. Prokop, D. Hunkeler, R. Green, K. Shahrokhi, and A. C. Powers (1997) An encapsulation system for the immuno-isolation of pancreatic islets.Nat. Biotechnol. 15: 358–362.Google Scholar
  100. [100]
    Yang, H., R. James, and J. Wright (1999) Calcium alginate. pp. 79–89. In: W. M. Kuhtreiber, R. P. Lanza, and W. L. Chick (eds.),Cell Encapsulation Technology and Therapeutics. Birkhauser, Boston, USA.Google Scholar
  101. [101]
    Soon-Shiong, P., M. Otterlie, G. Skjak-Braek, O. Smidsrod, R. Heintz, R. P. Lanza, and T. Espevik (1991) An immunologic basis for the fibrotic reaction to implanted microcapsules.Transplant. Proc. 23: 758–759.Google Scholar
  102. [102]
    Clayton, H. A., N. J. M. London, P. S. Colloby, P. R. E. Bell, and R. F. L. James (1991) The effect of capsule composition on the biocompatibility of alginate-poly-l-lysine capsules.J. Microencapsulation 8: 221–233.Google Scholar
  103. [103]
    Shu, X. Z. and K. J. Zhu (2000) A novel approach to prepare tripolyphosphate/chitosan complex beads for controlled release drug delivery.Int. J. Pharm. 201: 51–58.Google Scholar
  104. [104]
    Whateley, T. L. (1996) Microcapsules: preparation by interfacial polymerization and interfacial complexation and their application. pp. 349–375. In: S. Benita (ed.).Microencapsulation: Methods and Industrial Applications. Dekker, New York, USA.Google Scholar
  105. [105]
    Mathiowitz, E. and M. R. Kreitz (1999). Microencapsulation. pp. 493–546. In: E. Mathiowitz (ed.),Encyclopedia of Controlled Drug Delivery. Jone Wiley & Sons, Inc., New York, USA.Google Scholar
  106. [106]
    Watnasirichaikul, S., N. M. Davies, T. Rades, and I. G. Tucker (2000) Preparation of biodegradable insulin nanocapsules from biocompatible microemulsions.Pharm. Res. 17: 684–689.Google Scholar
  107. [107]
    Debenedetti, P. G., J. W. Tom, S. Yeo, and G. Lim (1993) Application of supercritical fluids for the production of sustained delivery devices.J. Controlled Release 24: 27–44.Google Scholar
  108. [108]
    Knutson, B. L., P. G. Debenedetti, and J. W. Tom (1996) Preparation of microparticulates using supercritical fluids. pp. 89–125. In: S. Cohen and H. Bernstein (eds.),Microparticulate Systems for the Delivery of Proteins and Vaccines. Marcel Dekker, Inc., New York, USA.Google Scholar
  109. [109]
    Ghaderi, R., P. Artursson, and J. Carlfors (1999) Preparation of biodegradable microparticles using solution-enhanced dispersion by supercritical fluids (SEDS).Pharm. Res. 16: 676–681.Google Scholar
  110. [110]
    Tom, J. W., G.-B. Lim, P. G. Debenedetti, and R. K. Prud'homme (1993) Application of supercritical fluids in the controlled release of drugs. In: E. Kiran and J. E. Brennecke (eds.),ACS Symposium Series 514: Supercritical Fluid Engineering Science fundamentals and applications. American Chemical Society, Washington, D.C., USA.Google Scholar
  111. [111]
    Soppimath, K. S., T. M. Aminabhavi, A. R. Kulkarni, and W. E. Rudzinski (2001) Biodegradable polymeric nanoparticles as drug delivery devices.J. Controlled Release 70: 1–20.Google Scholar
  112. [112]
    Debenedetti, P. G., J. W. Tom, and S. Yeo (1993) Supercritical fluids: A new medium for the formulation of particles of biomedical interest.Proc. Int. Symp. Controlled Release Bioact. Mater., July 25–30. Washington D.C., USA.Google Scholar
  113. [113]
    Winters, M. A., B. L. Knutson, P. G. Debenedetti, H. G. Sparks, T. M. Przybycien, C. L. Stevenson, and S. J. Prestrelski (1996) Precipitation of proteins in supercritical carbon dioxide.J. Pharm. Sci. 85: 586–594.Google Scholar
  114. [114]
    Randolph, T. W., A. D. Randolph, M. Mebes, and S. Yeung (1993) Sub-micrometer-sized biodegradable particles of PLA via the gas antisolvent spray precipitation process.Biotechnol. Prog. 9: 429–435.Google Scholar
  115. [115]
    Young, T.J., K.P. Johnston, K. Mishima, and H. Tanaka (1999) Encapsulation of lysozyme in a biodegradable polymer by precipitation with a vapor-over-liquid anti-solvent.J. Pharm. Sci. 88: 640–650.Google Scholar
  116. [116]
    Bodmeier, R., H. Wang, D. J. Dixon, S. Mawson, and K. P. Johnston (1995) Polymeric microspheres prepared by spraying into compressed carbon dioxide.Pharm. Res. 12: 1211–1217.Google Scholar

Copyright information

© The Korean Society for Biotechnology and Bioengineering 2001

Authors and Affiliations

  1. 1.Departments of Pharmaceutics and Biomedical EngineeringPurdue UniversityWest LafayetteUSA

Personalised recommendations