Partial specific volume

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The partial specific volume $\backslash bar\{v\_i\},$ express the variation of the extensive volume of a mixture in respect to composition of the masses. It is the partial derivative of volume with respect to the mass of the component of interest.

:$V=\backslash sum\; \_\{i=1\}^n\; m\_i\; \backslash bar\{v\_i\},$

where $\backslash bar\{v\_i\}$ is the partial specific volume of a component $i$ defined as:

:$\backslash bar\{v\_i\}=\backslash left(\; \backslash frac\{\backslash partial\; V\}\{\backslash partial\; m\_i\}\; \backslash right)\_\{T,P,m\_\{j\backslash neq\; i\}\}.$

The PSV is usually measured in milliLiters (mL) per gram (g), proteins > 30 kDa can be assumed to have a partial specific volume of 0.708 mL/g.{{cite book |last1=Buxbaum |first1=Engelbert |title=Biophysical Chemistry of Proteins |url=https://archive.org/details/biophysicalchemi00buxb_979 |url-access=limited |date=2011 |publisher=Springer |location=New York, Dordrecht, Heidelberg, London |isbn=978-1-4419-7250-7 |pages=[https://archive.org/details/biophysicalchemi00buxb_979/page/n236 237]–249 |chapter=25: Centrifugation|doi=10.1007/978-1-4419-7251-4_25 }} Experimental determination is possible by measuring the natural frequency of a U-shaped tube filled successively with air, buffer and protein solution.{{cite book |author1=Kratky, O. |author2=Leopold, H. |author3=Stabinger, H. |editor1=Hirs, C.H.W. |editor2=Timasheff, S.N. |title=Meth. Enzymol. Vol. 27: Enzyme Structure Part D|date=1973 |isbn=978-0-12-181890-6 |pages= 98–110 |chapter=5: The determination of the partial specific volume of proteins by the mechanical oscillator technique}}