A non-thermal microwave plasma sterilisation system using automatic tuning contained within the hand-piece of teh applicator

摘要

This invention relates to a system and method of generating non-thermal plasma using microwave energy and a single or combination of gases for sterilisation of biological tissue and other surfaces where an automatically adjustable tuning mechanism contained inside the applicator or antenna is used to enable the plasma to be effectively struck, maintained, and matched into the treatment tissue or surface to ensure optimal sterilisation effect. A system of introducing controlled levels of moisture into the applicator to assist with the production of hydroxyl radicals is also disclosed. The system comprises: a waveguide antenna structure containing a section of waveguide 280, tuning elements 250, 260, 270, an actuator to control the position of the tuning elements within the waveguide 240, a means of coupling microwave energy into the waveguide 160, 210, 220, and a means of coupling gas into the waveguide 170, 230. The rest of the system consists of a controlled source of modulated microwave energy 10, 20, 30, 40, 50, 60, 70, a means of measuring forward going and reflected microwave energy 80, 90, a means of detecting magnitude and/or phase information 100, a suitable gas or gas mixture, and a means of introducing the gas into the antenna 130, 150, 200, a means controlling the operation of the system, and a user interface unit 120. Apparatus for producing controllable non-thermal plasma comprising a controllable microwave energy source, an antenna, means for automatically matching the microwave energy with antenna structure whereby the control system is integrated into the antenna or hand-piece and is implemented using a combination of analogue components is also claimed.