POLAROGRAPHIC-BEHAVIOR AND DETERMINATION OF BECLOMETHASONE DIPROPIONATE

The polarographic behaviour of beclomethasone dipropionate in Britton- Robinson buffers containing 40% methanol as a solubilizer has been stu died. Over the pH range 1.8-12, a cathodic wave was produced, which wa s characterised as being irreversible, diffusion controlled and free f rom adsorption phenomena. The number of electrons involved in the redu ction was found through comparative study with spironolactone. Using d irect current polarographic mode, the limiting current concentration p lot is rectilinear over the range 2.5 X 10(-5) to 4 x 10(-4) mol/l wit h a detection limit of 2.5 x 10(-6) mol/l. A method has been developed for the determination of the drug in aerosols and creams, the results being in agreement with those obtained by the official method.