should be completely immersed in the liquid nitrogen
(Fig. 2b).
10. Much attention should be paid in this step due to the vapor
generated from the liquid nitrogen. This vapor could potentially freeze the vaccine formulation at the dropper or pipette
tip, preventing the deposition of the rest of formulation into
the vial. To avoid this issue, try to find the optimum distance
from the bottom of the vial where it is possible to drop the
vaccine without freezing. It is also recommended to use personal protective equipment during this process.
11. The volume of the vaccine formulation should not exceed
250 μL in a 20 mL glass vial to avoid formation of overlapped
thin films.
Acknowledgments
The authors acknowledge that research supporting this work was
funded by a sponsored research agreement from TFF Pharmaceuticals, Inc. (Austin, TX). R.F.A. was supported, in part, by a scholarship from the King Saud University. C.M. was supported, in part,
by TFF Pharmaceuticals.
References
1. Kristensen D, Chen D, Cummings R (2011)
Vaccine stabilization: research, commercialization, and potential impact. Vaccine 29
(41):7122–7124
2. Clausi A, Cummiskey J, Merkley S, Carpenter
JF, Braun LJ, Randolph TW (2008) Influence
of particle size and antigen binding on effectiveness of aluminum salt adjuvants in a model
lysozyme vaccine. J Pharm Sci 97
(12):5252–5262
3. Shi S, Zhu H, Xia X, Liang Z, Ma X, Sun B
(2019) Vaccine adjuvants: understanding the
structure and mechanism of adjuvanticity. Vaccine 37(24):3167–3178
4. Chen D, Kristensen D (2009) Opportunities
and challenges of developing thermostable vaccines. Expert Rev Vaccines 8(5):547–557
5. World Health Organization (2006) In: Galazka
AM (ed) Temperature sensitivity of vaccines.
World Health Organization, Geneva
6. Thakkar SG, Cui Z (2017) Methods to prepare
aluminum salt-adjuvanted vaccines. In: Vaccine
adjuvants, Methods in molecular biology, vol
1494. Springer, New York, pp 181–199
7. Zapata MI, Peck GE, Hem SL, White JL, Feldkamp JR (1984) Mechanism of freeze-thaw
instability of aluminum hydroxycarbonate and
magnesium hydroxide gels. J Pharm Sci 73
(1):3–8
8. Maa YF, Zhao L, Payne LG, Chen D (2003)
Stabilization of alum-adjuvanted vaccine dry
powder formulations: mechanism and application. J Pharm Sci 92(2):319–332
9. Diminsky D, Moav N, Gorecki M, Barenholz Y
(1999) Physical, chemical and immunological
stability of CHO-derived hepatitis B surface
antigen (HBsAg) particles. Vaccine 18
(1–2):3–17
10. Boros CA, Hanlon M, Gold M, Roberton D
(2001) Storage at À3
C for 24 h alters the
immunogenicity of pertussis vaccines. Vaccine
19(25–26):3537–3542
11. Matthias DM, Robertson J, Garrison MM,
Newland S, Nelson C (2007) Freezing temperatures in the vaccine cold chain: a systematic
literature review. Vaccine 25(20):3980–3986
12. Nygaard UC, Samuelsen M, Aase A, Løvik M
(2004) The capacity of particles to increase
allergic sensitization is predicted by particle
number and surface area, not by particle mass.
Toxicol Sci 82(2):515–524
Thin-Film Freeze-Drying Is a Viable Method to Convert Vaccines Containing. . .
497
(Fig. 2b).
10. Much attention should be paid in this step due to the vapor
generated from the liquid nitrogen. This vapor could potentially freeze the vaccine formulation at the dropper or pipette
tip, preventing the deposition of the rest of formulation into
the vial. To avoid this issue, try to find the optimum distance
from the bottom of the vial where it is possible to drop the
vaccine without freezing. It is also recommended to use personal protective equipment during this process.
11. The volume of the vaccine formulation should not exceed
250 μL in a 20 mL glass vial to avoid formation of overlapped
thin films.
Acknowledgments
The authors acknowledge that research supporting this work was
funded by a sponsored research agreement from TFF Pharmaceuticals, Inc. (Austin, TX). R.F.A. was supported, in part, by a scholarship from the King Saud University. C.M. was supported, in part,
by TFF Pharmaceuticals.
References
1. Kristensen D, Chen D, Cummings R (2011)
Vaccine stabilization: research, commercialization, and potential impact. Vaccine 29
(41):7122–7124
2. Clausi A, Cummiskey J, Merkley S, Carpenter
JF, Braun LJ, Randolph TW (2008) Influence
of particle size and antigen binding on effectiveness of aluminum salt adjuvants in a model
lysozyme vaccine. J Pharm Sci 97
(12):5252–5262
3. Shi S, Zhu H, Xia X, Liang Z, Ma X, Sun B
(2019) Vaccine adjuvants: understanding the
structure and mechanism of adjuvanticity. Vaccine 37(24):3167–3178
4. Chen D, Kristensen D (2009) Opportunities
and challenges of developing thermostable vaccines. Expert Rev Vaccines 8(5):547–557
5. World Health Organization (2006) In: Galazka
AM (ed) Temperature sensitivity of vaccines.
World Health Organization, Geneva
6. Thakkar SG, Cui Z (2017) Methods to prepare
aluminum salt-adjuvanted vaccines. In: Vaccine
adjuvants, Methods in molecular biology, vol
1494. Springer, New York, pp 181–199
7. Zapata MI, Peck GE, Hem SL, White JL, Feldkamp JR (1984) Mechanism of freeze-thaw
instability of aluminum hydroxycarbonate and
magnesium hydroxide gels. J Pharm Sci 73
(1):3–8
8. Maa YF, Zhao L, Payne LG, Chen D (2003)
Stabilization of alum-adjuvanted vaccine dry
powder formulations: mechanism and application. J Pharm Sci 92(2):319–332
9. Diminsky D, Moav N, Gorecki M, Barenholz Y
(1999) Physical, chemical and immunological
stability of CHO-derived hepatitis B surface
antigen (HBsAg) particles. Vaccine 18
(1–2):3–17
10. Boros CA, Hanlon M, Gold M, Roberton D
(2001) Storage at À3
C for 24 h alters the
immunogenicity of pertussis vaccines. Vaccine
19(25–26):3537–3542
11. Matthias DM, Robertson J, Garrison MM,
Newland S, Nelson C (2007) Freezing temperatures in the vaccine cold chain: a systematic
literature review. Vaccine 25(20):3980–3986
12. Nygaard UC, Samuelsen M, Aase A, Løvik M
(2004) The capacity of particles to increase
allergic sensitization is predicted by particle
number and surface area, not by particle mass.
Toxicol Sci 82(2):515–524
Thin-Film Freeze-Drying Is a Viable Method to Convert Vaccines Containing. . .
497