Chromatography Forum

Hi ,

How would you tackle a force deg study (acid ,base and peroxide) with a API that was insoluble in water, since 0.1M conc are aqueous
Use organic and solvents but how would these be use as acid ,base and peroxide conditons


Much appreciated

I'd use some amount of organic, water-miscible solvent such as methanol, ethanol, acetonitrile, DMF or the like to dissolve the compound and then add the aqueous stressing agent. You may have to experiment a bit with the amount of organic so that the compound does not precipitate upon addition of the aqueous part.
Final concentration of your stressing agent of course will depend upon the mixing ratio organic/aqueous, but does this matter? You want to see the right amount of degradation (which, by the way, may need considerable time for optimization of the stressing conditions), so I wouldn't worry if the final concentration is 0.1M or 0.08M or whatever.