论文部分内容阅读
光热效应是激光与生物组织相互作用中的一个主要因素,但其产生、传输和作用机理尚不十分清晰.本文采用双波长近红外激光辐照和膜片钳技术相结合的方法,选择980nm和845nm两个波长的近红外激光,因其在水中的吸收系数分别为0.502cm-1和0.0378cm-1,接近十倍差异.若溶液是产生光热响应的主要介导物质,则期望这两个波长的激光辐照所产生的溶液温升也将呈现相应的十倍比例关系.研究中把溶液光热响应过程分为温升的建立和耗散两个阶段.在温升建立阶段,理论模型的建立采用长时程(激光作用时程长于介质的热弛豫时间)作用理论的研究结果,实验是使用膜片钳系统来测量细胞外溶液中,已进行温度标定的、充灌溶液的玻璃微电极电导变化,根据这个电导变化来定量研究溶液光热响应与其吸收特性的关联性;在耗散阶段,使用膜片钳系统监测神经细胞的电生理功能变化.理论和实验两方面的结果都表明,溶液对低强度近红外激光的吸收特性决定了其光热响应.这一结果,可以直接用于生物组织光热响应特性相关的机理研究.
The photothermal effect is one of the main factors in the interaction between laser and biological tissue, but its mechanism of production, transmission and mechanism is not yet clear.In this paper, a combination of dual-wavelength near-infrared laser irradiation and patch-clamp technique was used to select 980nm and The near-infrared laser at both wavelengths of 845 nm has a nearly ten-fold difference due to its absorption coefficient in water of 0.502 cm -1 and 0.0378 cm -1, respectively. If the solution is the major mediator of photothermal response, The temperature rise of the solution generated by laser irradiation will also show a ten-fold proportional relationship.The solution is divided into two stages: the establishment of the temperature rise and the dissipation.As the theory The model was established using the long-term (laser-induced duration longer than the thermal relaxation time of the medium) theory of action, using a patch-clamp system to measure the temperature in the extracellular solution, which has been temperature-calibrated, The conductance of the glass microelectrode varies with the change of conductance to quantitatively study the relationship between the photothermal response of the solution and its absorption characteristics. During the dissipative phase, the electrophysiological function of the nerve cell is monitored using a patch clamp system The results of both theoretical and experimental studies show that the absorption characteristics of low intensity NIR laser in solution determine its photothermal response, which can be directly used to study the mechanism of photothermal response of biological tissues.