The Study Of Electret Fluorouracil Gel Patch

In this paper, we chose 5-fluorouracil (5-FU) as model drug, Azone as chemical enhancer, polypropylene (pp) as the backing layer of the patch and electret material to prepare the negative electret 5-FU gel patches with different surface potential using corona charging method and pharmaceutical method. The formulation prescription, transport mechanism of drug in skin, charge storage stability, piezoelectric properties were studied to explore the safety and effectiveness of the system, as well as the enhancing mechanism of the electrets. Besides, we built the hyperplastic scar model in SD rat and tested the efficacy of the system, in the hope of creating a new method to cure the hyperplastic scar.During the prescription of the patch, we screened the adhesives, moistening agent and the mixed order of components by preliminary experiment. The optimal matrix proportion in the blank gel patch was obtained with orthogonal design. The factors of adhesive and moistening agent were considered according to the skin irritation, adhesive power, skin following, ect. The research results indicated that the 5-FU gel patch has a good quality. The adhesives power, skin following and the other sensory indicators were meet the requirements and the gel patch had the advantage of safety, non-irritation, well-distributed content and good charge storage stability.By the research of piezoelectric, we found that all the negative electrets used in the study could result in the polarization of the model drug and chemical penetration enhancers in patch.In the study of transport mechanism of drug in skin in vitro, drug content in the receptor liquid and the SC stripped skin were studied. The results indicated that reasonable regulation of the external electrostatic field and microcurrent, as well as the polar electric field of the electret could effectively control the release of 5-FU. Both the negative polarity electrets and 3% Azone could enhance the transdermal delivery of the model drug. Electret 5-FU gel patch could not only increase the transdermal permeation of the drug, but also had the long term effect and controlled release of the drug.In this study, we successfully built the hyperplastic scar model in SD rat and tested the efficacy of the system. However, we did not find the positive result of the system. It may be caused by the limitation of the study method, so we should do the advanced research to prove the efficacy of the system in hyperplastic scar.In conclusion, the electret 5-FU gel patch had good charge storage stability, it could effectively accelerate the model drug diffusion from the patch to SC and penetrate through the skin and into therapeutic targets.