The Immersion Cell (p/n PSIMCELL-UN) is a test system designed for ointments, creams, lotions, etc., for quality control purposes. It can be used on a standard dissolution system in combination with small volume paddle and a flat bottom mini dissolution vessel. The ointment is sealed in a delivery chamber where it can only move into the solution through a membrane. One of the recommended membranes for this test is the Hydrophobic Polysulfone, 0.45µm, ø25mm (p/n PSMDC-PS25-045-0100).