DEVELOPMENT OF A TRANSDERMAL DELIVERY DEVICE FOR MELATONIN IN-VITRO STUDY

The present study was undertaken to develop a transdermal delivery dev ice for melatonin and to determine the effects of system design on the release of melatonin. Melatonin(MT) diffusion characteristics from 2 solvents through a series of ethylene vinyl acetate membranes with 4.5 %, 9%, 19%, 28% vinyl acetate were characterized using vertical Franz( R) diffusion cells. The solvent used were 40% (v/v) propylene glycol ( PG) and 40%(v/v) propylene glycol with 30%(w/v) 2-hydroxypropyl-beta-c ytrodextrin. The best release rate (Jss = 0.795 mu g/h/cm(2)) was obta ined from the 40% PG vehicle through the 28% vinyl acetate membrane. M elatonin diffusion through this membrane with an acrylate pressure sen sitive adhesive (PSA) with and without MT loading was also studied. Th e data revealed an interaction between MT and the PSA in the systems w ith MT-loaded adhesive. A MT transdermal delivery device was construct ed based on the above data. Effect of storage time (1 day, 2 days, and 3 days) on the developed device was also investigated. Steady state f lux values of MT did not vary significantly with storage time (p-value = 0.14). The steady state flux was 1.88 +/- 0.6 mu g/hr/cm(2)(n = 9). However, storage time did affect the burst effect of MT. Total amount of MT released in the first hour was 137.4 +/- 25.7 mu g after 3 days , 61.5 +/- 8.9 mu g after 2 days, and 43.8 +/- 20.9 mu g after 1 day.