Department of Chemistry, Faculty of Science, Tallinn University of Technology, Tallinn, Estonia.
Anal Chem. 2009 Oct 15;81(20):8590-5. doi: 10.1021/ac9015825.
A new sample introduction/analysis approach was developed by combining a digital microfluidic (DMF) device with a portable capillary electrophoresis (CE) analyzer based on short separation capillary and contactless conductivity detection. The DMF sample injection was performed by transporting sample and buffer droplets in succession under the CE capillary inlet end allowing the capillary to be immersed into the sample/buffer droplet, and CE separation was performed by applying a high voltage between the (grounded) buffer droplet and CE outlet reservoir. Electrowetting on dielectric (EWOD) phenomenon was used for droplets actuation. With the use of the DMF sampler, CE separation of a mixture of vitamins was achieved. A droplet evaporation process with simultaneous concentration of sample in the droplet was monitored. It was found that the concentration process closely followed the theoretically predicted function.
一种新的样品引入/分析方法是通过将数字微流控（DMF）装置与基于短分离毛细管和非接触式电导检测的便携式毛细管电泳（CE）分析仪相结合而开发的。DMF 样品的进样是通过在 CE 毛细管入口端连续输送样品和缓冲液滴来实现的，允许毛细管浸入样品/缓冲液滴中，CE 分离是通过在（接地的）缓冲液滴和 CE 出口储液器之间施加高压来实现的。电润湿（EWOD）现象用于控制液滴的运动。使用 DMF 采样器，实现了维生素混合物的 CE 分离。监测了在液滴中同时浓缩样品的液滴蒸发过程。结果发现，浓缩过程非常符合理论预测的函数。
