Related Experiment Video
Updated: Feb 1, 2026

Freezing, Thawing, and Packaging Cells for Transport
Published on: July 2, 2008
Freeze/thaw of IGG solutions
Jacqueline Horn1, Sampeeti Jena2, Alptekin Aksan2
1Department of Pharmacy-Pharmaceutical Technology and Biopharmaceutics, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.
In this communication, the effect of mannitol and trehalose crystallization on the unfolding of IgG1, a monoclonal antibody, in the frozen state with repeat freeze/thaw under different pH conditions was explored. Formulations were annealed at -20 °C for 20 h five times (interrupted by freeze/thaw). This was done to induce excipient crystallization. Characterization of the frozen-thawed samples was performed by circular dichroism, particle analysis, and size exclusion chromatography. At a pH of 3, formation of insoluble and soluble aggregates was observed however, these could be reduced by the use of a surfactant. Cryoprotectant free formulations showed higher monomer content after freeze/thaw. At pH5, a single freeze/thaw cycle did not result in a significant increase in particle numbers. At pH range of 4-7 however, aggregate formation in the size range of 1-25 µm was observed after 5freeze/thaw cycles.
In this communication, the effect of mannitol and trehalose crystallization on the unfolding of IgG1, a monoclonal antibody, in the frozen state with repeat freeze/thaw under different pH conditions was explored. Formulations were annealed at -20 °C for 20 h five times (interrupted by freeze/thaw). This was done to induce excipient crystallization. Characterization of the frozen-thawed samples was performed by circular dichroism, particle analysis, and size exclusion chromatography. At a pH of 3, formation of insoluble and soluble aggregates was observed however, these could be reduced by the use of a surfactant. Cryoprotectant free formulations showed higher monomer content after freeze/thaw. At pH5, a single freeze/thaw cycle did not result in a significant increase in particle numbers. At pH range of 4-7 however, aggregate formation in the size range of 1-25 µm was observed after 5freeze/thaw cycles.
Related Concept Videos
Transcytosis of IgG
IgG molecules from a mother undergo transcytosis starting around 13 weeks of gestation. The amount of IgG transferred and entering the fetal blood circulation increases with...
Freezing Point Depression and Boiling Point Elevation
The boiling point of a liquid is the temperature at which its vapor pressure is equal to ambient atmospheric pressure. Since the vapor pressure of a solution is lowered due to the presence of nonvolatile solutes, it stands to reason that the solution’s boiling point will subsequently be increased. Vapor pressure increases with temperature, and so a solution will require a higher temperature than will pure solvent to achieve any given vapor pressure, including one...
Phase Transitions: Melting and Freezing
Ideal Solutions
General Properties of Solutions
Solution Formation
This selective...

