Rotation based multi-channel bio-luminescence detection system

• Main Authors: Te-chyuan Lee, 李得全
• Other Authors: Shyh-Liang Lou
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/21768204255897014134

碩士 === 中原大學 === 醫學工程研究所 === 96 === This thesis study aims on the design and development of a rotation based multi-channel bio-luminescence detection system. The system mainly consists of a photomultiplier tube (PMT), a tube rotator, a control circuit and a cage. The PMT detects, amplifies and converts light photons to analog voltage signals. A microprocessor, MSP430F1611, is the core component of the control circuit. It transforms the analog signals into digital. The tube rotator includes a dark lucite disk that is rotated by a motor, which is also controlled by microprocessor. On the surface near the edge of the disk, three open holes were designed so that the diameter of the holes is just able to hold the designated tubes. The aforementioned components were assembled within the cage. Effort was made to ensure light photons can not be in and out the cover of the cage is closed. The detected signals are digitally transferred to a computer for curve plotting. The developed system was evaluated in the aspects of the background noise and the stability of the rotation speed. The background noise study was performed in a setup that the cage was closed and then the system was powered on. The result indicated the background noise was about 6 mV. The rotation speed of the lucite disk in the rotator is determined by the microprocessor. It issues a rotation speed index value (RSIV) representing the time duration of each angular movements (or steps). The index value is inversely proportion to the rotation speed. According to the experimental results, the operable RSIV range from 55 to 500 for the tube rotator used in this work. The rotation speed stability was determined by the angular steps that are required to move the disk from one tube hole to the next adjacent one. The study results show that the steps between any two adjacent tube holes are about 63 steps. Based on this finding, an experiment was carried out to study number of rotation cycles required to stabilize the speed when the tube rotator is in rest initially. The results indicate the rotator needs 2~3 cycles to stabilize its rotation speed approximately.