| abstract |
This invention relates to a method and an analytical device for the determination of solubility of a compound. The basic method involves determinig solubility of a compound by measuring the UV spectrum of a reference solution of the compound, under conditions avoiding or suppressing precipitation, and comparing it to the UV spectrum of a saturated sample solution of the compound. Variations of the basic method include: (a) making reference solutions either by dilution of the sample solution to the point where precipitation is avoided, or by adding a water-miscible cosolvent to the sample solution so that precipitation is suppressed, and comparing the UV absorbances of the compound under reference conditions to the compound in a saturated solution, (b) determining the true aqueous solubility from the effect on the pKa that results from dissolving the compound in an aqueous solution containing some DMSO (typically 0.1 - 5% v/v), and (c) correcting concentrations determined from the UV absorbance values for impurities. |