Pi Xitian

Design of site specific delivery capsule based on MEMS

Site specific delivery capsule (SSDC) is a new method to realize non-invasive drug delivery to the selected sites of the human alimentary tract. With SSDC, non-invasive regional drug absorption (RDA) studies are taken to provide the pharmacokinetics data for oral drug formulation development. In this research, a new SSDC has been developed based on MEMS technology. An innovative drug release actuator was designed with simple and reliable structure, which includes a micro-heater array, an elastomeric bellows and a piston. The power of the compressed elastomeric bellows driven the piston to expelled drug out of the capsule. Piston was adhibited to the micro-heater array by low melting point adhesive. The power consumption of the micro-heater array has been decreased to 450 mJ by MEMS technology. A magnetic marker monitoring (MMM) system was developed to monitor the location of the capsule inside the human alimentary tract by providing three- dimensional location data. We get the pharmacokinetic characteristics data of aminophylline (150 mg) in the proximal small intestine of 12 healthy volunteers with the SSDC.

A Novel Remote Controlled Capsule for Human Drug Absorption studies

Remote Controlled Capsule (RCC) is a new method to realize non-invasive drug delivery to the selected sites of human gastro-intestinal (GI) tract. With RCC, Human Drug Absorption (HDA) studies are taken easily to obtain data on the intestinal absorption of a drug in humans. In this paper, a new RCC system has been designed based on MEMS technology to provide for the delivery of a wide range of different drug formulations, for example, solution, powder and granulate, into any region of the gut. A magnetic Marker Monitoring (MMM) system was developed to monitor the location of the capsule inside the gut. A novel method to indicating the drug release, called as Indicating System based on Abrupt Movement of Marker (ISAMM), was proposed in this study. High reliability of the RCC system has been proved by animal experiments.