基于流式细胞仪的折射率渐变微流体透镜的仿真及试验验证

Considered as new transformation optofluidic devices, Liquid Gradient Refractive Index (L-GRIN) microlens can implement adjustable focusing and interference capabilities. It has become a hot investigation in the joint application of optofluidics with biomedicine because of its small size, easy of modularization, and having the potential to turn Lab-on-Chip of flow cytometer which integrates the characteristics of flow injection, reaction, separation and detection into reality. However, how to accurate control the micro- and nanoscale flow and realize controllable and predictable optical characteristic of microlens is one key issues needed to be solved in the study and application of microlens. Trigged by our preliminary results obtained from theoretical analysis and device design, we expect to establish a connection between the diffusion convection process of fluid dynamics and the optical property of microlens by checking the effect of various liquid/device factors, including the structure and size of device, the flow velocity, concentration and temperature of liquids, etc., on the diffusion convection process of liquids, as well as the features of wave-manipulation of L-GRIN microlens under different conditions. This project is expected to provide more understanding to the optical response mechanism of L-GRIN microlens, and contribute to its optical characteristics with high control accuracy, and the realization of Lab-on-Chip of flow cytometry with tunable microlens.

基于折射率渐变微流体（L-GRIN）的微透镜作为一种新型的转换光学器件，能实现光束动态聚焦、干涉等功能。因其尺寸微小、易于模块化，有望实现集进样、反应、分离、检测等多种功能于一体的快速、高效、低功耗型流式细胞“芯片实验室”（Lab-on-Chip），成为光流控技术在生物医学领域的研究热点。然而如何在微纳尺度下对流体流动状态进行精确控制，实现微透镜的功能可控、可预测成为微透镜发展与应用亟待解决的难题。基于我们前期理论分析及器件设计的初步结果，本项目拟研究微通道中流体扩散对流动力学过程及其折射率渐变机理。通过探测不同流体/器件因素，包括器件结构、尺寸、流体流速、浓度、温度等对流体扩散对流过程及微透镜光束调控效果的影响，深入探讨其内在关联，从微观层次上揭示微透镜的光学响应机制，实现微透镜的功能可控，开发出基于流式细胞仪的光束动态可调的微流体光学控制平台。

基于折射率渐变微流体（L-GRIN）的微透镜作为一种新型的转换光学器件，能实现对光束动态、实时的整形功能。因其尺寸微小、易于模块化，有望实现集进样、反应、分离、检测等多种功能于一体的快速、高效、低功耗型流式细胞“芯片实验室”（Lab-on-Chip），成为光流控技术在生物医学领域的研究热点。本项目建立了光流体理论模型，研究微通道中流体扩散对流动力学过程及其折射率渐变机理；开发出基于微流体芯片的光学高速成像平台：通过探测不同流体/器件因素，包括器件结构、尺寸、流体流速、浓度、温度等对流体扩散对流过程及微透镜光束调控效果的影响，实现微透镜μm级精度的聚焦功能；另外，利用模型计算不同尺寸微纳米粒子在光流体环境中的受力，预测其运动轨迹；设计出基于流体力学及等离子共振效应的光流体芯片，利用微流体粘弹性力及光学剪切力对细胞分类，并用探测系统实现对所分离细胞信息的实时收集与分析；基于该探测系统设计纳米级“流式细胞仪”。