图生一 Propellants 国生 ©Raoult'slaw ©Formulation of MDI P.=N.P9=po ·Solution aerosols na+np P.=N,Po=m po ·Suspension aerosols na+np P=P+P 国丝生一 图上生 ©Formulation of MDI ©Formulation of MDI ·Solution aerosols ·Suspension aerosols Reduce initial particle size to less than 5um ·Propellant Control moisture content ·Cosolvent Use drug derivatives having minimum solubility ·Surfactant Adjust density of propellant and drug particles Use dispersing agents 国生一 圆生 ©Valve ©Container ·Plastic coated glass Metal (aluminum)container ·Plastic container 55 Shanghai Jiao Tong University Propellants Raoult’s law a b b a b b b b b a a b a a a a P P P P n n n P N P P n n n P N P         0 0 0 0 Shanghai Jiao Tong University Formulation of MDI • Solution aerosols • Suspension aerosols Shanghai Jiao Tong University Formulation of MDI • Solution aerosols • Propellant • Cosolvent • Surfactant Shanghai Jiao Tong University Formulation of MDI • Suspension aerosols • Reduce initial particle size to less than 5um • Control moisture content • Use drug derivatives having minimum solubility • Adjust density of propellant and drug particles • Use dispersing agents Shanghai Jiao Tong University Container • Plastic coated glass • Metal (aluminum) container • Plastic container Shanghai Jiao Tong University Valve