Abstract: The present invention is directed to devices useful for determining the release profile of a macromolecule from a pharmaceutical composition comprising the macromolecule and methods of using the device. Transport of a macromolecule across a semi-permeable barrier is measured as a function of time using the device, the results of which can correlate with an in vivo release of the macromolecule from a pharmaceutical composition, a bioavailability of the macromolecule, or the stability or purity of the pharmaceutical composition comprising the macromolecule.

Abstract: A drug release cell useful in testing the drug release of a product in a liquid includes a first chamber and a second chamber with a membrane positioned in between such that the first chamber is located above the membrane and the second chamber is located below the membrane. The membrane has pores sized to permit a liquid and a released product, such as an insulin suspension, disposed in the second chamber to pass therethrough. When the drug release cell is filled with liquid and product is present in the second chamber the liquid is mixed with a mixing device to circulate the liquid and disperse released media throughout the liquid. Samples are taken at predetermined times from the first chamber through a sampling port to determine the concentration of the product in the liquid. The concentration data may then be utilized to create a drug release profile.