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Title: Buffer effects on protein sieving losses in ultrafiltration and their relationship to biophysical properties
Abstract The design of effective ultrafiltration/diafiltration processes for protein formulation requires the use of membranes with very high protein retention. The objective of this study was to examine the effects of specific buffers on the retention of a model protein (bovine serum albumin) during ultrafiltration. Albumin retention at pH 4.8 was significantly reduced in phosphate buffer compared with that in acetate, citrate, and histidine. This behavior was consistent with a small change in the effective albumin hydrodynamic diameter as determined by dynamic light scattering. The underlying conformational changes leading to this change in diameter were explored using circular dichroism spectroscopy and differential scanning calorimetry. These results provide important insights into the factors controlling protein retention during ultrafiltration and diafiltration.  more » « less
Award ID(s):
2310832 1841474
PAR ID:
10644482
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Biotechnology Progress
Volume:
40
Issue:
6
ISSN:
8756-7938
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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