Watts Benjamin R, Zhang Zhiyi, Xu Chang Qing, Cao Xudong, Lin Min
Department of Engineering Physics, McMaster University, Hamilton, Canada.
Electrophoresis. 2014 Feb;35(2-3):271-81. doi: 10.1002/elps.201300195. Epub 2013 Oct 7.
SU-8-based photonic-microfluidic integrated devices with on-chip beam shaping and collection capabilities were demonstrated in a scattering detection and counting application. Through the proper deployment of the tailored beam geometries via the on-chip excitation optics, excellent CV values were measured for 1, 2, and 5 μm blank beads, 16.4, 11.0, and 12.5%, respectively, coupled with a simple free-space optical detection scheme. The performance of these devices was found dependent on the combination of on-chip, lens-shaped beam geometry and bead size. While very low CVs were obtained when the combination was ideal, a nonideal combination could still result in acceptable CVs for flow cytometry; the reliability was confirmed via devices being able to resolve separate populations of 2.0 and 5.0 μm beads from their mixture with low CV values of 15.9 and 18.5%, respectively. On-chip collection using integrated on-chip optical waveguides was shown to be very reliable in comparison with a free-space collection scheme, yielding a coincident rate of 94.2%. A CV as low as 19.2% was obtained from the on-chip excitation and collection of 5 μm beads when the on-chip lens-shaped beam had a 6.0-μm beam waist.
基于SU-8的光子微流体集成器件具有片上光束整形和收集能力，已在散射检测和计数应用中得到展示。通过片上激发光学器件对定制光束几何形状的适当部署，对于1μm、2μm和5μm的空白微珠，分别测得优异的变异系数（CV）值为16.4%、11.0%和12.5%，同时采用了简单的自由空间光学检测方案。发现这些器件的性能取决于片上透镜形光束几何形状和微珠尺寸的组合。当组合理想时可获得非常低的变异系数，而不理想的组合仍能得到可接受的流式细胞术变异系数；通过器件能够从2.0μm和5.0μm微珠的混合物中分辨出不同群体，其变异系数分别低至15.9%和18.5%，从而证实了可靠性。与自由空间收集方案相比，使用集成片上光波导进行片上收集被证明非常可靠，重合率为94.2%。当片上透镜形光束的束腰为6.0μm时，对5μm微珠进行片上激发和收集可获得低至19.2%的变异系数。
