School of Engineering, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Lab Chip. 2012 Apr 7;12(7):1251-4. doi: 10.1039/c2lc21025h. Epub 2012 Feb 15.
We present a novel optofluidic differential method for carrying out absorbance spectroscopy of sub-nanolitre volumes of liquid samples on a microfluidic chip. Due to the reduction of liquid volume, the absorbance detection in microfluidics is often hindered by either low sensitivity or complex fabrication. To address this issue, we introduced an optofluidic modulator which can be easily integrated into a PDMS (polydimethylsiloxane) based microfluidic chip. The modulator was controlled by the fluid pressure and the absorbance spectrum of the analyte was obtained by taking differential measurements between the analyte and reference medium. An advantage is that this method doesn't need a complicated fabrication step. It is compatible with conventional microfluidic chips and measurements can be carried out on a normal transmission microscope. The performance of the device was tested by measuring solutions containing methylene blue, with concentrations as low as 13 μM.
我们提出了一种新颖的光流体差分式方法，可在微流控芯片上对亚纳升级别的液体样品进行吸光度光谱测量。由于液体体积的减少，微流控中的吸光度检测常常受到灵敏度低或制造复杂的阻碍。为了解决这个问题，我们引入了一种光流体调制器，它可以很容易地集成到基于 PDMS（聚二甲基硅氧烷）的微流控芯片中。该调制器由流体压力控制，通过对分析物和参考介质进行差分测量来获得分析物的吸光度谱。一个优点是，这种方法不需要复杂的制造步骤。它与传统的微流控芯片兼容，并且可以在普通透射显微镜上进行测量。该设备的性能通过测量含有亚甲蓝的溶液进行了测试，浓度低至 13 μM。
