ABSTRACT
Objective To develop a light source system for the treatment of rectal cancer photodynamic therapy based on magnetic coupling resonant wireless power supply technology.Methods The proposed system consists of the implant and the external power supply device.The implant includes a light source and a resonant receiving coil.The light source is a 650 nm LED.The light source and the receiving coil were encapsulated with transparent epoxy to benefit the implantation and biocompatibility.The external power supply device was based on the magnetic coupling resonant technology,and the frequencies of the high frequency inverter and the natural frequency of the transmitting coil and the receiving coil were set at the same resonant frequency to ensure the efficient transmission of energy.Results The power density range of the light source is 3～22 mW/cm2 in the vertical distance range of 50～ 180 mm to the plane of the transmitting coil.Conclusions In the proposed light source system,the LED was separated from the power source.The size of the implant is small enough to be implanted,and the external power source can provide a real-time and stable energy supply for the implant.
ABSTRACT
Objective To propose the design of a pulsate blood pump driven by magnetic coupling and verify its feasibility. Methods The blood pump was designed based on the magnetic transmission reciprocating force model and the push-and-pull structure, and the coupling force was calculated by building the magnetic force-driven model. The prototype of the blood pump was then manufactured, on which the extracorporeal circulation simulation test was conducted to obtain the pressure and flow rate. Results Physiological saline was used as the circulation medium. When the afterload was fixed and increase the preload, the output of the blood pump would decrease, but showing no obvious linear trend. While the preload was fixed and increase the afterload, the output of the blood pump was reduced, showing a linear trend. With the driving frequency set as 75 per minute, and the preload and afterload adjusted in the range of 0.665-3.990 kPa (5-30 mmHg) and 5.320-11.970 kPa (40-90 mmHg), respectively, the output of the blood pump could reach 2.0-3.1 L/min while guaranteeing the linear relationship. Conclusions The proposed magnetic coupling-driven pulsate blood pump can basically meet the need of extracorporeal membrane pulmonary circulation, while it still needs further improvement. The research results have a valuable application prospect, especially with great significance in replacement of blood pump currently used in the extra-corporeal membrane oxygenation (ECMO) equipment in clinic.