Solubility tests - Shake flask

The shake flask method is the basic way of performing a solubility test. It requires simple equipment such as lockable flasks (conical flask, laboratory bottle, falcon tube), an oscillating shaker, an oven or incubator, syringes and syringe filters.

In a typical solubility test an excess amount of your compound is introduced into the flasks and covered with biorelevant medium of your choice (usual volumes are between 10 and 20 ml). The flasks are locked and can then be slightly shaken to improve wetting of your compound. Then the flasks are placed inside an oven/incubator on a shaker. The oven should be adjusted to the required temperature (usually 37° C) and the shaker should be turned on. To assess equilibrium solubility, the samples are taken after 24 hours of incubation. Alternatively, if you wish to find out more about the dynamics of the compound solubility, you can take samples at different time points.

The shake flask method requires sample filtration to separate non-dissolved compound from the solution. A simple way of filtering your samples is to use a syringe and syringe filters.


Sandra Klein: The Use of Biorelevant Dissolution Media to Forecast the In Vivo Performance of a Drug (2010)

Nikoletta Fotaki and Maria Vertzoni: Biorelevant Dissolution Methods and Their Applications in In Vitro - In Vivo Correlations for Oral Formulations (2010)