The Design For The Efficient Vitro Drug Delivery Device

A lot of assistance has been brought to mankind by the traditional syringe when injection.But there exist some problems in the practical use of the syringe.such as sharing needling may make infectious disease spread,pains,and long-term injection may produce the adverse factors such as subcutaneous nodules.Needle-free injector solve all the problems which the traditional syringe has,and Needle-free injector makes drug diffusion faster,also more healthier.In this thesis, one mathematical model of injection pressure for the needle-free injector powered by spring considering about the impact space between the the piston and the ampoule mandrel is built according to the process of the injection. The structure parameters are obtained by the simulation values. The needle-free injector powered by spring is made with the simulation results. The prototype has been given the functions of dose adjusting and once drug delivery injection repeatedly, and the insurance can avoid the error operation by the operator. Finally, the injection pressure model is verified with the prototype. The optimizing impact space can be confirmed from the jet pressure test.Another mathematical model of injection pressure for the needle-free injector powered by electromagnetic considering about the inductance of the coil is bulit according to the process of the injection. The structure parameters are obtained by the simulation values. The key parameters affecting the peak force of the motor are contrasted and analysed in the simulation. The needle-free injector powered by electromagnetic is made with the simulation results, and the controlled circuit which can operate by single key and inject continuously is made by the time-relay modules. Finally, the injection pressure model is verified with the prototype for the mathematical model. And injection depth and injection breadth are tested by the gel injection experiments...