Filter plate method solubility testing

Figure 12 Filter plate method for solubility testing. (1) Add compound dissolved in organic solvent to aqueous buffer. (2) Shake for 90 minutes to allow insoluble compound to precipitate. (3) Apply vacuum to filter solution into collection plate. Precipitates remain on membrane. Analyze filtrate in collection plate to quantify the amount of the compound still in the solution. Source Courtesy of Millipore Corporation, Billerica, Massachusetts, U.S.A.

Figure 4.12 Filter plate method for solubility testing.

Avdeef introduced an alternative approach. Aliquots of DMSO stock solutions are pipetted robotically into incubation well plate containing an aqueous buffer. The concentration of the test compound should be between 50-150 iM in order to keep the DMSO content below 0.5 %. After a time of incubation, the plate is filtered and the solved compound is quantified with an UV plate reader. The method is fast, robust and reported to be reliable (Kerns). 200-300 compounds can be measured per day. Additionally, pH solubility profiles can be set up easily (Kibbey). 

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