Basic Research On Evaluation Of Tumor With PDT Real-time Dynamic Treating Effect

Photodynamic Therapy(PDT) is a new method to kill tumor selectively, by using light, photosensitizer and oxygen. The photodynamic reaction will produce reactive oxygen species. PDT has advantages of good selectivity, however it also has some small side effects. In the clinical, PDT is lack of effective in vivo real-time evaluation methods. This paper is aimed at designing a system to monitor the singlet oxygen in the process of tumor treated with PDT.The main work of this paper includes: 1. Design the overall structure of the system, including photoelectric detection system, amplifying system and data acquisition system. The photoelectric detection part was using photomultiplier tube. The data acquisition part was based on data acquisition card. The Labview was used as the software development platform for real-time display and signal storage. 2. Cadence software system was used to design the PCB for the system core circuit part. An experiment was designed to find out the optimum control voltage range. 3. Design a metal shield for photomultiplier tube, which was used for reducing background noise and shielding the electromagnetic wave interference. The operation panel of the system and a weak fluorescence detection system instrument were built. 4. The verification experiment was designed. The fluorescence quantum dot concentration gradient experiments proved that the system was effective and the fluorescence signal could be converted to a corresponding electrical signal. Moreover, the output voltage value had a good consistency between the fluorescence intensity. The luminol chemical luminescence experiment showed that the fluorescence intensity had a positive correlation with the amount of a certain concentration of oxidant.The paper finally constructed a weak fluorescence signal acquisition system based on minimally invasive optical fiber probe. The feasibility of the system was validated by experiments. The paper provides the foundation for the basic research on evaluation of tumor with PDT real-time dynamic treating effect and the favorable conditions for the further study.