Solubility general equation

A series of studies has been made by Yalkowsky and co-workers. The so-called general solubility equation was used for estimating the solubility of solid nonelectrolytes [17, 18]. The solubility log S (logarithm of solubility expressed as mol/L) was formulated with log P logarithm of octanol/water partition coefficient), and the melting point (MP) as shown in Eq. (11). This equation generally... 

Yang G, Ran Y and Yalkowsky SH. Prediction of the aqueous solubility comparison of the general solubility equation and the method using an amended solvation energy relationship. J Pharm Sci 2002 91 517-33. 

Sanghvi, T., Jain, N Yang, G., Yalkowsky, S. Estimation of aqueous solubility by the general solubility equation (GSE) the easy way. QSAR Comh. Sci. 2003, 22, 258-262. 

Ran, Y., Jain, N., Yalkowsky, S.H. Prediction of aqueous solubility of organic compounds by the general solubility equation (GSEJ./. Chem. Inf. Comput. Sci. 2001, 41, 1208—1217. 

The other term frequently occurring in such equations is the octanol-water partition coefficient, logP. It describes the lipophilicity of the compound. It is related to water solubility by Yalkowski s general solubility equation (GSE) ]33, 34] ... 

Ran, Y. and Yalkowsky, S.H. (2001) Prediction of drug solubility by the general solubility equation (GSE). Journal of Chemical Information and Computer Sciences, 41, 354—357. 

A comprehensive review of this field is beyond the scope of this chapter. As for vapour pressure, the aim is to give easy-to-use tools for non-specialists in the field. The general solubility equation, initially introduced by Yalkowski and Valvany [47], then revised by the same team [48], is probably the simplest ... 

Yalkowsky (1981) has developed equations describing water solubility as a function of both hydrophobicity (locP) and crystal lattice forces. Jain and Yalkowsky (2001) have offered a new general solubility equation, where the molar solubility, %) of a nonelectrolyte can be estimated by... 

Jain et al. (2006) have demonstrated that the general solubility equation is also useful for weak... 

The prediction of aqueous solubility is more complex compared to lipophilicity. Frequently, solubility models incorporate log P as one of the descriptors. Yalkowsky considered a physical model of the solubilization and provided a theoretical basis of the link between log P and solubility of molecules in his General Solubility Equation (GSE). The 2001 version of GSE is amazingly simple ... 

Yalkowsky [29,30] united both of these empiric relations and theoretically derived the general solubility equation (GSE). The derivation of the equation included three hypothetical steps. First, the analyzed crystal was heated until it melted. Next, the melted liquid was cooled to the water temperature, and eventually, the compound was dissolved in water. The equation was revised in 2001 by considering that the complete miscibility of a compound in octanol corresponds to a mole fraction of X0 = 0.5 rather than to X0 = 1 for each component [31]. The current GSE is written as... 

Several approaches have been applied to predict the melting point, but all of them result in prediction errors of 35-45 °C [9, 10] and can therefore not be regarded as accurate enough to be included in solubility calculations. Hence, the prediction of solubility from the general solubility equation (GSE) established by Yalkowsky and coworkers [6] still requires the experimentally determined melting point. Other typical molecular descriptors included in solubility predictions are molecular size, hydrogen bonding, nonspecific van der Waals interactions, aromaticity, flexibility, and dipole moment [11-17]. 

A predictive estimation is available through the use of the General Solubility Equation defined and developed by Yalkowsky et al This simple but effective equation for nonelectrolytes was derived using sound thermodynamic principles to establish the semi-empirical correlation ... 

The luminal oversaturation number is a dimensionless number that cannot be less than unity and distinguishes between drugs that are soluble in the gastrointestinal contents from drugs that are not. The former will dissolve readily, whereas the latter will exist as suspensions that will maintain a saturated solution in the gut until sufficient absorption has taken place so that no suspended particles remain. For the calculation of solubility, the general solubility equation of Jain-Yalkowsky is used [Yalkowsky, 1999 Jain and Yalkowsky, 2001] ... 

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