NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Liquid-Liquid Phase Separation in Supersaturated Lysozyme Solutions and Associated Precipitate Formation/CrystallizationUsing cloud point determinations, the phase boundaries (binodals) for metastable liquid-liquid (L-L) separation in supersaturated hen egg white lysozyme solutions with 3%, 5%, and 7% (wlv) NaCl at pH= 4.5 and protein concentrations c between 40 and 400 mg/ml were determined. The critical temperature for the binodal increased approximately linearly with salt concentration. The coexisting liquid phases both remained supersaturated but differed widely in protein concentration. No salt repartitioning was observed between the initial and the two separated liquid phases. After the L-L separation, due to the presence of the high protein concentration phase, crystallization occurred much more rapidly than in the initial solution. At high initial protein concentrations, a metastable gel phase formed at temperatures above the liquid binodal. Both crystal nucleation and gel formation were accelerated in samples that had been cycled through the binodal. Solutions in the gel and L-L regions yielded various types of precipitates. Based on theoretical considerations, previous observations with other proteins, and our experimental results with lysozyme, a generic phase diagram for globular proteins is put forth. A limited region in the (T,c) plane favorable for the growth of protein single crystals is delineated.
Document ID
19990047382
Acquisition Source
Marshall Space Flight Center
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Muschol, Martin
(Alabama Univ. Huntsville, AL United States)
Rosenberger, Franz
(Alabama Univ. Huntsville, AL United States)
Date Acquired
August 19, 2013
Publication Date
August 1, 1997
Publication Information
Publication: Journal of Chemical Physics
Publisher: American Institute of Physics
Volume: 107
Issue: 6
ISSN: 0021-9606
Subject Category
Solid-State Physics
Funding Number(s)
CONTRACT_GRANT: NAG8-1161
CONTRACT_GRANT: NAG8-1168
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available