소수성 가소제 Diethylphthalate가 Ethylcellulose 필름으로부터의 살리씰산 방출에 미치는 영향

Effect of Diethylphthalate on the Release of Salicylic Acid from Ethylcellulose Films

Release characteristics of salicylic acid from ethylcellulose(EC) films containing varying ratio of dieththylphthalate (DEP) were studied. Mathematical analysis of the release data showed that the release behavior actually conforms with the Higuchi's diffusion-controlled model. The release rate constants(k) were independent from the film thickness and the pH of release medium, but were proportional to the concentration of salicylic acid itself. The logarithm of the release rate constant (log k) increased as the concentration of DEP was increased. In conclusion, hydrophobic plastisizer DEP seemed to be very useful in controlling release rate constant of slightly soluble drugs as like salicylic acid without changing it's release characteristics.