Permeation Characteristic of Silk Micro-Particle Controlling by External Electric Field

Transdermal iontophoresis is the system that delivers the ionic active ingredient through skin controlling by applying low-level electric current. In this research work, silk micro-particle (MS) was selected as active ingredient. MS loaded gelatin hydrogel (MS/Ge) was prepared for facial mask application. The effect of crosslinking agent and electrical voltage on physical, chemical and permeation characteristic of MS from gelatin hydrogel (Ge) was investigated. The passive and iontophoresis permeation characteristic was conducted by Modified Franz Diffusion Cell at pH 7.4, 37 °C for 24 h under applying electrical voltage of 0, 0.01. 0.05, 0.1 and 0.3 V. To study the effect of crosslinking agent, Ge was prepared at various amount of crosslinker (5, 10, 15, and 20 %(w/w) for MS/Ge/Ga_1, MS/Ge/Ga_2, MS/Ge/Ga_3 and MS/Ge/Ga_4, respectively). The %swelling of MS/Ge was first characterized. The % swelling of MS/Ge/Ga_1, MS/Ge/Ga_2, MS/Ge/Ga_3 and MS/Ge/Ga_4 was 1533.55%, 1154.71%, 1200.76% and 1026.59%, respectively. The amount of MS permeation increased with hydrogel mesh size which corresponds to % swelling of Ge. For iontophoresis permeation, the amount of MS permeation was higher than passive permeation due to electro-repulsive force and expansion of hydrogel pore size. The permeation kinetic was calculated. The permeation was controlled by nonfickian diffusion. The amount of micro silk particle permeation was controlling by amount of crosslinker and electrical voltage. Micro silk particle loaded gelatin hydrogel will be alternative material for cosmetic product.