Abstract:
:An interactive program is described for calculating the second virial coefficient contribution to the thermodynamic nonideality of solutions of rigid macromolecules based on their triaxial dimensions. The FORTRAN-77 program, available in precompiled form for the PC, is based on theory for the covolume of triaxial ellipsoid particles [Rallison, J. M., and S.E Harding. (1985). J. Colloid Interface Sci. 103:284-289]. This covolume has the potential to provide a magnitude for the second virial coefficient of macromolecules bearing no net charge. Allowance for a charge-charge contribution is made via an expression based on Debye-Hückel theory and uniform distribution of the net charge over the surface of a sphere with dimensions governed by the Stokes radius of the macromolecule. Ovalbumin, ribonuclease A, and hemoglobin are used as model systems to illustrate application of the COVOL routine.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Harding SE,Horton JC,Jones S,Thornton JM,Winzor DJdoi
10.1016/S0006-3495(99)77398-4subject
Has Abstractpub_date
1999-05-01 00:00:00pages
2432-8issue
5eissn
0006-3495issn
1542-0086pii
S0006-3495(99)77398-4journal_volume
76pub_type
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