Photo-thermal Effect Of Laser Stimulation Of Biological Cells

With the development of laser medicine in recent years, the laser provides a new way to study the life sciences. The laser is becoming an important means for people to study biological tissue. The interaction of laser and biological tissues has become an important foundation problem. Laser and biological cell interactions will generate the photo-thermal effect; it is one of the main important forms of interaction of laser with biological tissue. The temperature is an important parameter to characterize the photo-thermal effect. According to the tissue temperature rise and duration, the photo-thermal effect of the laser with the organization can be divided into condensation, vaporization, carbonization, cozy and so on. On the electro-physiological structure of the cell level, laser stimulation has gradually become an important means of people to study the function of the cell ion channel. In the infrared laser to stimulate biological cell sodium channel subject to change its channel function, we have established the heat-transfer-model with the thermal interaction between laser and biological cells. Using the finite element simulation techniques analyze thermal process of the interaction between laser and biological cells. This research process is divided into three processing, first to establish a three-dimensional finite element model of interacting heat transfer process between light and biological cells; second, we simulate the process of temperature field of the pulsed laser stimulation of the photo-thermal effect; final termination of laser irradiation, simulation the transient temperature field of process of the cell cooling. On the basis of this study, it was established kinetics process of the sodium channel channels, and studied the electrical activity of the sodium channel which is under the action of the laser to stimulate the cells in the photo-thermal effect.This article briefly discusses the basic theory of ion channels; the progress of biological cells in ion channel research of the laser stimulation, laser and biological tissues; the basic mechanism of thermal.interaction between laser and biological; the light distribution of the biological tissues, the basic theory of heat transfer and the heat transfer equations’solving conditions; cell thermal model of bio-heat transfer equation for the numerical solution of the finite element method; using the finite element analysis of ANSYS workbench software to analyze the process of bio-heat transfer in cylindrical coordinates, to obtain the temperature field distribution of the thermal model of laser irradiation of biological cells. Using the existing biological organizational parameters and laser parameters simulate the heat transfer processing of the model created by the laser irradiated cells. Finally, using the temperature field distribution data of the photo-thermal effect and conducted a preliminary study of the temperature dependence of the sodium channel. The results of the heat transfer simulation in this study show that:The use of light produced by the980nm laser irradiation cell heat transfer model thermal effects is much greater than the effect of845nm laser irradiation; Pulsed laser irradiating the photo-thermal effect of the model have relationship to the chopping frequency of the irradiating laser, the laser chopping frequency of the lower laser radiation the photo-thermal effect generated is more obvious; The photo-thermal effect occurs mainly in the cytosol of light absorption process, the photo-thermal effect of the cytosol plays a dominant role, the cell membrane of the photo-thermal effect is minimal.