Table 2.

Best fit equations for the preferential interaction co-efficient at constant co-solute chemical potential, Γμ₃, and transfer free energy, Δμ_{2, transfer,} as a function of excipient molality. The preferential interaction co-efficient data for trehalose and NaCl was fitted using a linear fitting algorithm and that for L-arginine.HCl was fitted using a non-linear fitting algorithm in Origin. The error bars in the bracket denote the standard error of fit. Transfer free energy values, Δμ_{2, transfer} were calculated by integrating the fitting equations for ${\mu }_{23,4}$ as a function of excipient molality (m₃) for the indicated combinations of protein and excipient at room temperature using vapor pressure osmometry technique.

		Γμ3 (mol/mol)	Δμ2,transfer (kJ/mol)
Trehalose	mAbA	−93.2 ( ± 0.7) m3	257.2 m3 − 33.0 m32
	mAbB	−106.8 ( ± 0.8) m3	289.6 m3 − 51.8 m32
	mAbC	−153.4 ( ± 0.9) m3	429.3 m3 − 96.1 m32
NaCl	mAbA	−71.9 ( ± 0.2) m3	332.1 m3 − 10.9 m32
	mAbB	−77.6 ( ± 0.1) m3	350.3 m3 − 17.4 m32
	mAbC	−77.0 ( ± 0.2) m3	354.0 m3 − 19.0 m32
L-arginine.HCl	mAbA	−32.2 ( ± 1.1) m3 − 116.4 ( ± 2.7) m32	165.9 m3 + 138.5 m32 − 20.2 m33
	mAbB	−24.4 ( ± 0.9) m3 − 141.8 ( ± 2.2) m32	141.8 m3 + 178.6 m32 − 21.5 m33
	mAbC	−53.5 ( ± 1.2) m3 − 189.1 ( ± 2.9) m32	268.9 m3 + 244.7 m32 − 56.0 m33