Microneedle Study Of Transdermal Drug De-Livery Based On Micro-injection Compression Technology

Transdermal drug delivery(TDD)compared with traditional oral and subcutaneous injection methods can prevent the liver from being stimulated by drugs.TDD has the advantages of sustained drug release and long-term drug delivery.Microneedle(MNs)is a new type of transdermal penetration en-hancement technology.MNs deliver drugs efficiently and have the benefits of painless minimally invasive.Microneedle technology is expected to be the main route for transdermal drug delivery.This paper proposes a mi-cro-injection compression molding process based on the micro-injection molding process.The process not only has the advantages of low cost of micro injection molding,simple process and high replication rate,but also superior to micro-injection molding in forming effect.This paper aims to study the advantages of micro-injection compression molding over conventional injection molding processes.The process can not only improve the forming effect,but also can realize the preparation of the flexible substrate microneedle array.The effect of microneedle length on insu-lin transdermal penetration was also investigated.The main research contents are as follows:(1)This paper presents the microscopic mechanism of microinjection compression molding.Designing a microneedle array and a molding die for the micro-injection compression molding process,a triangular pyramid solid microneedle will be designed.The microneedle has a height of 350 ?m and the bottom is an equilateral triangle with a side length of 260 ?m.Force analysis and strength check of designed microneedles by using Abaqus software.The overall structure of the micro-injection compression molding die was opti-mized,and the molding effect of the micro-injection compression molding and micro-injection molding process was analyzed by Moldflow.(2)In this paper,the polymer microneedle molding experimental scheme was designed,and the optimal process parameters of micro-injection compression molding polymer microneedles were obtained.The experimental results were used to analyze the significance of microinjection compression molding for microneedle molding.The paper analyzed the different process parameter combined with the micro-scopic mechanism of micro-injection compression molding.(3)This paper tests the mechanical properties of the prepared polymer microneedles.The feasibility of microneedle was verified by visual observa-tion of skin after microneedle treatment and experiment of insulin transdermal penetration.In the experiment,different types and different sizes of micronee-dles were used to compare the effects of microneedle geometric length on transdermal permeation,and a dimensionless model was established.The op-timal scale analysis was used to draw the corresponding conclusions for transdermal penetration.Research provides a technical basis.