Surface characterisation of freeze-dried protein/carbohydrate mixtures
Millqvist-Fureby, Anna LU ; Malmsten, Martin LU and Bergenståhl, Björn LU
(1999)
In International Journal of Pharmaceutics
191(2).
p.103-114
- Abstract
In the present investigation freeze-drying of proteins (BSA or trypsin) together with various carbohydrates, i.e. lactose, sucrose, mannitol, α-cyclodextrin and dextrin, has been studied with particular emphasis on the surface composition of the freeze-dried powders. The proteins were found to be over-represented on the powder surface as compared to the bulk concentration of protein. The mechanism behind the surface accumulation is believed to be that proteins adsorb preferentially over carbohydrates to the ice/liquid interface in the frozen sample. The degree of surface accumulation depended on the carbohydrate used, and was increased in annealed samples compared to reference samples. The activity of trypsin was fairly well preserved... (More)
In the present investigation freeze-drying of proteins (BSA or trypsin) together with various carbohydrates, i.e. lactose, sucrose, mannitol, α-cyclodextrin and dextrin, has been studied with particular emphasis on the surface composition of the freeze-dried powders. The proteins were found to be over-represented on the powder surface as compared to the bulk concentration of protein. The mechanism behind the surface accumulation is believed to be that proteins adsorb preferentially over carbohydrates to the ice/liquid interface in the frozen sample. The degree of surface accumulation depended on the carbohydrate used, and was increased in annealed samples compared to reference samples. The activity of trypsin was fairly well preserved (58-90%) in the freeze-dried powders, but depended on the carbohydrate excipient, whilst the surface composition had little effect on the activity. The activity preservation was improved when the protein concentration was raised from 1 to 10% in the solids. The surface composition of powders containing mixtures of mannitol and dextrin as excipients depended on the ratio between the two carbohydrates, with the lowest surface coverage of protein obtained in 50/50 mixtures. Copyright (C) 1999 Elsevier Science B.V.
(Less)
- author
- Millqvist-Fureby, Anna
LU
; Malmsten, Martin
LU
and Bergenståhl, Björn
LU
- publishing date
- 1999-11-30
- type
- Contribution to journal
- publication status
- published
- keywords
- BSA, ESCA, Freeze-drying, Surface analysis, Trypsin
- in
- International Journal of Pharmaceutics
- volume
- 191
- issue
- 2
- pages
- 12 pages
- publisher
- Elsevier
- external identifiers
-
- scopus:0032744304
- pmid:10564837
- ISSN
- 0378-5173
- DOI
- 10.1016/S0378-5173(99)00285-9
- language
- English
- LU publication?
- no
- id
- 9207b163-00d9-40be-9ed6-001e7a0c4f79
- date added to LUP
- 2025-04-14 17:32:07
- date last changed
- 2025-04-23 11:24:09
@article{9207b163-00d9-40be-9ed6-001e7a0c4f79,
abstract = {{<p>In the present investigation freeze-drying of proteins (BSA or trypsin) together with various carbohydrates, i.e. lactose, sucrose, mannitol, α-cyclodextrin and dextrin, has been studied with particular emphasis on the surface composition of the freeze-dried powders. The proteins were found to be over-represented on the powder surface as compared to the bulk concentration of protein. The mechanism behind the surface accumulation is believed to be that proteins adsorb preferentially over carbohydrates to the ice/liquid interface in the frozen sample. The degree of surface accumulation depended on the carbohydrate used, and was increased in annealed samples compared to reference samples. The activity of trypsin was fairly well preserved (58-90%) in the freeze-dried powders, but depended on the carbohydrate excipient, whilst the surface composition had little effect on the activity. The activity preservation was improved when the protein concentration was raised from 1 to 10% in the solids. The surface composition of powders containing mixtures of mannitol and dextrin as excipients depended on the ratio between the two carbohydrates, with the lowest surface coverage of protein obtained in 50/50 mixtures. Copyright (C) 1999 Elsevier Science B.V.</p>}},
author = {{Millqvist-Fureby, Anna and Malmsten, Martin and Bergenståhl, Björn}},
issn = {{0378-5173}},
keywords = {{BSA; ESCA; Freeze-drying; Surface analysis; Trypsin}},
language = {{eng}},
month = {{11}},
number = {{2}},
pages = {{103--114}},
publisher = {{Elsevier}},
series = {{International Journal of Pharmaceutics}},
title = {{Surface characterisation of freeze-dried protein/carbohydrate mixtures}},
url = {{http://dx.doi.org/10.1016/S0378-5173(99)00285-9}},
doi = {{10.1016/S0378-5173(99)00285-9}},
volume = {{191}},
year = {{1999}},
}