Design and Simulation of Microneedle Arrays for Transdermal Drug Delivery by Electroporation

Abstract

Transdermal drug delivery is one of the most efficiency way in transporting drug into human body Compared to traditional method transdermal drug delivery features in fast less side effect specific drug control In modern medicine the main idea not only focus on the efficiency of treatment but also puts emphasize at patient’s feeling Microneedle can reduce painful feeling apparently compares to traditional subcutaneous injection due to its small diameter Furthermore microneedle is an effective tool which has been under developed in past decades Besides drug delivery microneedle can applied to gene therapy target treatment against cancer especially for carcinoma and for vaccine Microneedle can be divided into several types due to its pathway such as hollow coat and poke dissolving Hollow microneedle combines with microfluidic and microneedle patch form a whole device Although hollow microneedle reveals good efficiency in drug delivery there are still some disadvantages In this article the aim is addressing design concept of “coat and poke” microneedle which combines with electric field “Coat and poke” microneedle type is with protein-based drug coated or DNA-based vaccine at the surface of microneedle As microneedle is made of metal material which is electrically conductive it can exert electric field in human skin conducts electroporation to enhance efficiency of drug delivery Furthermore microneedle is in micro diameter (100~500μm) while it provides sufficient mechanical strength to penetrate skin without mechanical fracture and prevent patient feeling painful In this study microneedle with shorter length(8°) show the greater ability to resist mechanical failure Besides diameter material selection is also a critical factor of design Three types of material are chosen which are Titanium Beta-21S Stainless Steel 316L Ni-Co-Cr-Mo alloy Among these materials Titanium Beta-21S shows the widest range of application so this material is recommended to microneedle application To evaluate efficiency of drug delivery diluted species and electric field distribution are important things for indicating which kinds of microneedle is better Three kinds of design are applied rectangular array hexagon array with 4 potentials and hexagon array with 6 potentials From the simulation result hexagon array with 4 potentials can provide the largest effective volume formed by concentration and electric field at time=9s so that it reveals the appropriate moment to conduct electric field to reach greater efficiency Combined with different physics this study addresses design concept of microneedle array and hope that it can be applied in future

Date of Award	2019
Original language	English
Supervisor	Han-Sheng Chuang (Supervisor)