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AAPS PharmSciTech. 2005 December; 6(4): E641–E648.
Published online 2005 December 21. doi:  10.1208/pt060480
PMCID: PMC2750613

Liposomal dry powders as aerosols for pulmonary delivery of proteins


The purpose of this research was to develop liposomal dry powder aerosols for protein delivery. The delivery of stable protein formulations is essential for protein subunit vaccine delivery, which requires local delivery to macrophages in the lungs. β-Glucuronidase (GUS) was used as a model protein to evaluate dry powder liposomes as inhaled delivery vehicles. Dimyristoyl phosphatylcholine:cholesterol (7[ratio]3) was selected as the liposome composition. The lyophilization of liposomes, micronization of the powders, aerosolization using a dry powder inhaler (DPI), and in vitro aerodynamic fine particle fraction upon collection in a twinstage liquid impinger were evaluated. After lyophilization and jet-milling, the total amount of GUS and its activity, representing encapsulation efficiency and stability, were evaluated. The GUS amount and activity were measured and compared with freshly-prepared liposomes in the presence of mannitol, 43% of initial GUS amount, 29% of GUS activity after lyophilization and 36% of GUS amount, 22% of activity after micronization were obtained. Emitted doses from dry powder inhaler were 53%, 58%, 66%, and 73% for liposome powder:mannitol carrier ratios of 1[ratio]0, 1[ratio]4, 1[ratio]9, and 1[ratio]19. Fifteen percent of the liposome particles were less than 6.4 μm in aerodynamic diameter. The results demonstrate that milled liposome powders containing protein molecules can be aerosolized effectively at a fixed flow rate. Influences of different cryoprotectants on lyophilization of protein liposome formulations are reported. The feasibility of using liposomal dry powder aerosols for protein delivery has been demonstrated but further optimization is required in the context of specific therapeutic proteins.

Keywords: protein, liposome, lyophilization, dry powders, aerosol, pulmonary delivery

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Selected References

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1. Ahmed T. Clinical testing of aerosol drugs. Boca Raton, FL: CRC Press; 1990. pp. 208–242.
2. Schreier H, Gonzales-Rothi RJ, Stecenko AA. Pulmonary delivery of liposomes. J Control Release. 1993;24:209–223. doi: 10.1016/0168-3659(93)90180-D. [Cross Ref]
3. Zeng XM, Martin GP, Marriott C. The controlled drug delivery to the lung. Int J Pharm. 1995;124:149–164. doi: 10.1016/0378-5173(95)00104-Q. [Cross Ref]
4. Gilbert BE, Wyde PR, Wilson SZ, Robins RK. Aerosol and intraperitoneal administration of ribavarin and ribavarin triacetate: pharmacokinetics and protection of mice against intracerebral infection with influenza A/WDN virus. Antimicrob Agents Chemother. 1991;35:1448–1453. [PMC free article] [PubMed]
5. Parthasarathy R, Gilbert B, Mehta K. Aerosol delivery of liposomal all-trans retinoic acid to the lungs. Cancer Chemother Pharmacol. 1999;43:277–283. doi: 10.1007/s002800050895. [PubMed] [Cross Ref]
6. Suntres ZE, Shek PN. Alleviation of paraquat-induced lung injury by pretreatment with bifunctional liposomes containing α-tocopherol and glutathione. Biochem Pharmacol. 1996;52:1515–1520. doi: 10.1016/S0006-2952(96)89626-2. [PubMed] [Cross Ref]
7. Briscoe P, Caniggia I, Graves A, et al. Delivery of superoxide dismutase to pulmonary epithelium via pH-sensitive liposomes. Am J Physiol. 1995;268:L374–L380. [PubMed]
8. Thibeault DW, Rezaiekhaligh M, Mabry S, Beringer T. Prevention of chronic pulmonary oxygen toxicity in young rats with liposome-encapsulated catalase administered intratracheally. Pediatr Pulmonol. 1991;11:318–327. doi: 10.1002/ppul.1950110408. [PubMed] [Cross Ref]
9. Saari M, Vidgren MT, Kiskinen MO, Turjanmaa VHM, Neiminen MM. Pulmonary distribution and clearance of 2 beclomethasone liposome formulations in healthy volunteers. Int J Pharm. 1999;181:1–9. doi: 10.1016/S0378-5173(98)00398-6. [PubMed] [Cross Ref]
10. Lange CF, Hancock REW, Samuel J, Finlay WH. In vitro delivery and regional airway surface liquid concentration of a liposomal cationic peptide. J Pharm Sci. 2001;90:1647–1657. doi: 10.1002/jps.1115. [PubMed] [Cross Ref]
11. Niven RW, Speer M, Schreier H. Nebulization of liposomes. I. Effects of lipid compositions. Pharm Res. 1992;9:515–520. doi: 10.1023/A:1015844430695. [PubMed] [Cross Ref]
12. Hickey AJ, Dunbar CA. A new millennium for inhaler technology. Pharm Technol. 1997;21:116–125.
13. Shreier H, Mobley WC, Concessio N, Hickey AJ, Niven RW. Formulation and in vitro performance of liposome powder aerosols. STP Pharma Sciences. 1997;4:38–44.
14. Lo Y, Tsai J, Kuo J. Liposomes and saccharides as carriers in spraydried powder formulations of superoxide dismutase. J Control Release. 2004;94:259–272. doi: 10.1016/j.jconrel.2003.09.019. [PubMed] [Cross Ref]
15. Joshi MR, Misra A. Liposomal budesonide for dry powder inhaler: preparation and stabilization. AAPS PharmSciTech. 2001;2:E25–E25. doi: 10.1208/pt020425. [PMC free article] [PubMed] [Cross Ref]
16. Joshi M, Misra A. Disposition kinetics of ketotifen from liposomal dry powder for inhalation in rat lung. Clin Exp Pharmacol Physiol. 2003;30:153–156. doi: 10.1046/j.1440-1681.2003.03813.x. [PubMed] [Cross Ref]
17. Jendle JH, Karlberg B, Arborelius M. An exploration of intrapulmonary insulin administration in anaesthetized and mechanically ventilated pigs. Scand J Clin Lab Invest. 1996;56:251–258. doi: 10.3109/00365519609088614. [PubMed] [Cross Ref]
18. Patton JS, Trinchero P, Platz RM. Bioavailability of pulmonary delivered peptides and proteins: α-interferon, calcitonins, and parathyroid hormone. J Control Release. 1994;28:79–85. doi: 10.1016/0168-3659(94)90155-4. [Cross Ref]
19. Colthorpe P, Farr SJ, Smith IJ, Wyatt D, Taylor G. The influence of regional deposition on the pharmacokinetics of pulmonary-delivered human growth hormone in rabbits. Pharm Res. 1995;12:356–359. doi: 10.1023/A:1016292232513. [PubMed] [Cross Ref]
20. Lizio R, Klenner T, Borchard G, et al. Systemic delivery of the GnRH antagonist cetrorelix by intratracheal instillation in anesthetized rat. Eur J Pharm Sci. 2000;9:253–258. doi: 10.1016/S0928-0987(99)00067-6. [PubMed] [Cross Ref]
21. Folkesson HG, Westrom BR, Pierzynowski SG, Svendsen J, Karlsson BW. Lung to blood passage of albumin and a nonapeptide after intratracheal instillation in the young developing pig. Acta Physiol. Scand. 1993;147:173–178. doi: 10.1111/j.1748-1716.1993.tb09486.x. [PubMed] [Cross Ref]
22. Russo DM, Kozlova N, Lakey DL, Kernodle D. Naive human T cells develop into Th1 effectors after stimulation with mycobacterium tuberculosis-infected macrophages or recombinant Ag85 proteins. Infect Immun. 2000;68:6826–6832. doi: 10.1128/IAI.68.12.6826-6832.2000. [PMC free article] [PubMed] [Cross Ref]
23. Lowry OH, Rosebrough NJ, Farr AL, Randall RJ. Protein measurement with the folin phenol reagent. J Biol Chem. 1951;193:265–275. [PubMed]
24. Combie J, Blake JW, Nugent TE, Tobin T. Morphine glucuronide hydrolysis: superiority of beta-glucuronidase from patella vulgata. Clin Chem. 1982;28:83–86. [PubMed]
25. Fisherman WH. Methods for determination of enzyme activity-III Hydrolases: β-Glucuronidase. In: Bergmeywe HU, editor. Methods of Enzymatic Analysis Volume 2. 2nd ed. New York, NY: Academic Press, Inc; 1974. pp. 929–943.
26. Stewart JC. Colorimetric determination of phospholipids with ammonium ferrothiocyanate. Anal Biochem. 1980;104:10–14. doi: 10.1016/0003-2697(80)90269-9. [PubMed] [Cross Ref]
27. Leonard A, Dufourc EJ. Interactions of cholesterol with the membrane lipid matrix: a solid state NMR approach. Biochimie. 1991;73:1295–1302. doi: 10.1016/0300-9084(91)90092-F. [PubMed] [Cross Ref]
28. Colletier JP, Chaize B, Winterhalter M, Fournier D. Protein encapsulation in liposomes: efficiency depends on interaction between protein and phospholipid bilayer. BMC Biotechnol. 2002;2:9–17. doi: 10.1186/1472-6750-2-9. [PMC free article] [PubMed] [Cross Ref]
29. Flores H, Ellington AD. Increasing the thermal stability of an oligomeric protein, beta-glucuronidase. J Mol Biol. 2002;315:325–337. doi: 10.1006/jmbi.2001.5223. [PubMed] [Cross Ref]
30. Hellman K, Miller DS, Cammack KA. The effects of freeze-drying on the quaternary structure of L-asparaginase from Erwinia Carotovora. Biochim Biophys Acta. 1983;749:133–142. [PubMed]
31. Clark AR, Egan M. Modeling the deposition of inhaled powdered drug aerosols. J Aerosol Sci. 1994;25:175–186. doi: 10.1016/0021-8502(94)90189-9. [Cross Ref]
32. The United States Pharmacopoeia and National Formulary. USP24. Rockville, MD: United States Pharmacopoeial Convention; 2000. pp. 1895–1912.
33. Hickey AJ, Swift D. Measurements of Pharmaceutical Diagnostic Aerosols. In: Baron PA, Willeke K, editors. Aerosol Measurement: Principles, Techniques and Applications. New York: Wiley; 2001. pp. 1031–1052.
34. Bell JH, Hartley PS, Cox JSG. Dry powder aerosols. I. A new powder inhalation device. J Pharm Sci. 1971;60:1559–1564. doi: 10.1002/jps.2600601028. [PubMed] [Cross Ref]
35. Winden EC, Zhang W, Crommelin DJ. Effect of freezing rate on the stability of liposomes during freeze-drying and rehydration. Pharm Res. 1997;14:1151–1160. doi: 10.1023/A:1012142520912. [PubMed] [Cross Ref]
36. Hatley RHM, Blair JA. Stabilization and delivery of labile materials by amorphous carbohydrates and their derivatives. J Mol Catal, B Enzym. 1999;7:11–19. doi: 10.1016/S1381-1177(99)00018-1. [Cross Ref]
37. Zeng XM, Martin GP, Marriot C. Effects of molecular weight of polyvinylpyrrolidone on the glass transition and crystallization of co-lyophilized sucrose. Int J Pharm. 2001;218:63–73. doi: 10.1016/S0378-5173(01)00613-5. [PubMed] [Cross Ref]
38. Shamblin SL, Huang EY, Zografi G. The effects of co-lyophilized polymeric additives on the glass transition temperature and crystallization of amorphous sucrose. J Therm Anal. 1996;47:1567–1579. doi: 10.1007/BF01992846. [Cross Ref]

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