Freeze-concentrated glass-like transition temperature of carbohydrate–phosphate buffered saline systems and impact on collapse of freeze-dried solids

Phosphate buffered saline (PBS) and carbohydrates are used to freeze-dried biomaterials. It has been suggested that PBS reduces the freeze-concentrated glass-like transition temperature ( T g ′ ) of carbohydrate solutions and that freeze-dried solids collapse readily during freeze-drying. In order t...

Full description

Saved in:
Bibliographic Details
Published in:Journal of thermal analysis and calorimetry 2020-10, Vol.142 (2), p.809-817
Main Authors: Yamamoto, Yukino, Hagura, Yoshio, Kawai, Kiyoshi
Format: Article
Language:English
Subjects:
Alcohols
Analytical Chemistry
Biological products
Biomedical materials
Buffers
Carbohydrates
Chemistry
Chemistry and Materials Science
Dextrins
Dextrose
Freeze drying
Glucose
Inorganic Chemistry
Inulin
Maltodextrin
Measurement Science and Instrumentation
Phosphates
Physical Chemistry
Polymer Sciences
Polyols
Sucrose
Sugar
Transition temperature
Trehalose
Water activity
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Phosphate buffered saline (PBS) and carbohydrates are used to freeze-dried biomaterials. It has been suggested that PBS reduces the freeze-concentrated glass-like transition temperature ( T g ′ ) of carbohydrate solutions and that freeze-dried solids collapse readily during freeze-drying. In order to obtain more insight into the subject, the effect of PBS on the T g ′ of trehalose solution was systematically investigated. The T g ′ of trehalose solution was found to be independent of the trehalose content. The T g ′ of trehalose–PBS solution, on the other hand, decreased with decreasing trehalose content. The behavior was described as a T g ′ curve for a trehalose–PBS pseudobinary system. The T g ′ curve was analyzed using the modified Gordon–Taylor equation, and the T g ′ of PBS was extrapolated to be 195.0 K. In order to compare the plasticizing effect of PBS, the T g ′ values of other carbohydrate materials including sugar alcohols (glucose, maltitol, sucrose, inulin, and maltodextrin) were also investigated. It was found that freeze-concentrated trehalose was more sensitive to the plasticizing effect of PBS than the other sugars. Finally, trehalose and trehalose–PBS solutions with varying trehalose content were freeze-dried, and their water activity ( a w ) and apparent volume ratio against pre-dried (frozen) solids ( V FD V F −1 ) were evaluated. Freeze-dried trehalose samples had low a w values and high V FD V F −1 values. Freeze-dried trehalose–PBS samples, on the other hand, had significantly higher a w values and lower V FD V F −1 values than freeze-dried trehalose samples depending on the trehalose content. These results corresponded to the T g ′ and initial solute content.
ISSN:1388-6150
1588-2926
DOI:10.1007/s10973-020-09626-7