Photoacousto-photothermal effect and temperature monitoring of tissues subjected to graphene oxide

Tissue local temperature information is necessary for guiding treatment parameters in photothermal therapy. Therefore, a temperature monitoring method suitable for the treatment process is needed for monitoring tissue temperature in real time. In this study, a temperature monitoring system based on PID on the photothermal effect of graphene oxide on tissue was proposed. Graphene Oxide (GO) has high photothermal conversion performance and low cytotoxicity under near infrared laser irradiation at 808nm. The photoacoustic imaging system and infrared thermal imager were employed to monitor the effect of GO as a photothermal agent on the photoacoustic signal and temperature of tissues. Firstly, the relationship between the intensity of photoacoustic signal and the temperature of tissues under the action of GO was established. Then, the PID feedback algorithm was applied to monitor and regulate the temperature change of tissues by the intensity of photoacoustic signal, so as to achieve the purpose of photothermal treatment. The results show that GO can enhance the photoacoustic signal of the tissue under laser irradiation and improve the temperature of the irradiated tissue. The system can effectively monitor and regulate the tissue temperature to achieve the therapeutic effect of tumor with little effect on normal tissue.