Design Of Remote Controlled Capsule Based On Micro-thruster

Recently there has been an increased interest in optimizing drug therapy by studying regional drug absorption (RDA). The goal of this ongoing research is to deposit clinical drug candidates absorbed in the critical residence areas from the gastrointestinal (GI) tract. With fierce competition in the field of international pharmacy and the great risk of drug research, human drug absorption studies develop further. However, conventional intubation or perfusion make the volunteers uncomfortable,and even make them traumatic.Because of the presence of catheter, the normal function of the GI tract has been changed, making drug absorption data inaccuracy.Therefore, more and more research organizations adobt Site-Specific Delivery Capsule (SSDC) to abtain drug absorption data.As the core part of SSDC,remote controlled capsule (RCC) grows rapidly. However, most RCCs commercially available or in development are compromised by incomplete or slow drug delivery, and thus are less desirable in RDA study.With the development of the micro-thruster, we propose that the micro-thruster will be used in RCC. Based on the SSDC we have completed, a novel micro-thruster for drug release in RCC has been designed.In this paper, the prototype in vitro of RCC based on micro-thruster was designed. It mainly includes micro-thruster, wireless remote controlled device, power modules, et.al. The working principle is that the remote controlled circuit gets start to work by the external magnetic field generator, and then the micro-thruster is triggered to produce high-energy gas to complete the drug release. This paper discussed how to realize the key technologies of the RCC, such as the micro-thruster, wireless remote control, and also the structure, micro-machining, dynamics analysis in gastrointestinal tract about the micro-thruster and wireless remote controlled circuit was discussed in details.As the RCC will be used in the human body, it must be a very high reliability. In this paper, assembly process of RCC was introduced in details and the various considerations of the assembly process were pointed out. At the same time, we have proposed the design of the reliability, and analyzed the reliability of the shell and micro-thruster. Low power design was proposed too. In addition, detailed tests in vitro about RCC were carried out. Through the ignition experiments, we proved the reliability of micro-thruster. The ignition voltage recorded in the experiment has proven its low power consumption. Experiment to magnetic switch on the remote controlled device has proved that the design of the magnetic holding switch can be used to maintain the wireless remote control with high trigger rate. Shell reliability experiment has proved it has a good seal. Finally, release experiments in vitro have demonstrated drug release by thruster has high safety. The mass of the theoretical propellant was optimized, and the difference between the theoretical and experimental value has been detailedly analyzed. Finally, it proved that the prototype in vitro of RCC based on micro-thruster can complete the drug release.The system of RCC based on micro-thruster has simple structure, and reliable performance, so it can complete the drug release excellently, and also it has solved the problems about the current RCC, such as uncompleted drug release, low trigger rate. RCCs based on micro-thruster will be expected to clinical application by further experiments.