液体环境对光镊稳定捕获的影响

发布时间：2018-04-10 22:40

本文选题：光镊 + 热梯度力　；参考：《纳米技术与精密工程》2017年06期

【摘要】：具有高精度和高灵敏度的光镊技术在生物领域,特别是生物单分子力谱测量中,有着广泛和重要的应用.对微米量级粒子的稳定捕获是光镊技术开展应用研究的基础.非水环境在生物单分子研究领域越来越受到重视,本文对不同液体环境影响光阱稳定捕获的热力学因素进行研究,结合热力学仿真建立了热梯度力模型,分析了微球在向会聚光束焦点横向运动过程中受到的热梯度力的变化,并与T矩阵理论仿真得到的光阱力空间分布进行比较,总结了液体环境影响热梯度力的关键参数.在异丙醇环境里捕获直径为5μm硅球的实验中,5μm硅球无法进入光阱.针对这一实验现象,结合实验中微球的运动状态,通过分析仿真的光阱力和热梯度力在空间上的分布差异,给出了合理的解释,证明了上述理论的可行性,为评估不同溶液环境里激光热效应对光阱捕获微球的影响提供了分析方法.
[Abstract]:Optical tweezers with high accuracy and sensitivity are widely used in biological field, especially in the measurement of biomolecular force spectrum.The stable capture of micron particles is the basis for the application of optical tweezers.Non-aqueous environment has been paid more and more attention in the field of biomolecular research. In this paper, the thermodynamic factors that affect the stability of optical trap in different liquid environments are studied, and the thermal gradient force model is established based on thermodynamic simulation.The variation of thermal gradient force in the transverse motion of the microsphere toward the focal point of convergent beam is analyzed and compared with the spatial distribution of optical trap force obtained by T-matrix theory. The key parameters of the influence of liquid environment on thermal gradient force are summarized.In the experiment of trapping 5 渭 m silicon spheres in isopropanol environment, the 5 渭 m silicon spheres cannot enter the optical trap.According to the experimental phenomenon and the motion state of the microspheres in the experiment, through analyzing the spatial distribution difference between the simulated optical trap force and the thermal gradient force, the reasonable explanation is given, and the feasibility of the above theory is proved.It provides an analytical method for evaluating the effect of laser thermal effect on the trapping microspheres in different solution environments.
【作者单位】：精密测试技术及仪器国家重点实验室(天津大学);加拿大英属哥伦比亚大学化学系;
【基金】：国家自然科学基金资助项目(61223008) 天津市自然科学基金资助项目(15JCZDJC31600)
【分类号】：TN24

【相似文献】