Microfluidic devises connected to fused-silica capillaries with minimal dead volume
Microfluidic devises connected to fused-silica capillaries with minimal dead volume
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DOI：
10.1021/ac981419z
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发表时间：
1999-08-01
影响因子：
7.4
通讯作者：
Harrison, DJ
中科院分区：
文献类型：
--
作者：
Bings, NH;Wang, C;Harrison, DJ
通过使用200微米的碳化钨钻头在微流控装置边缘钻孔，已将熔融石英毛细管连接到微流控装置上用于毛细管电泳。标准的尖头钻头钻出的孔底部呈圆锥形，在连接处导致0.7纳升的几何死体积，并且在与0.2纳升的样品塞一起使用时会出现明显的谱带展宽。在连接到芯片的熔融石英毛细管上获得的理论塔板数约为预测值的16 - 25%。用平头钻头去除圆锥形区域后，谱带展宽基本消除（平均观察到预测理论塔板数的98%）。所有测量都是在装置从毛细管末端进行电喷雾操作时进行的。平底连接的有效死体积极小，使得微流控装置能够连接到各种各样的外部检测器。
Fused-silica capillaries have been connected to microfluidic devices for capillary electrophoresis by drilling into the edge of the device using 200-mu m tungsten carbide drills. The standard pointed drill bits create a hole with a conical-shaped bottom that leads to a geometric dead volume of 0.7 nL at the junction, and significant band broadening when used with 0.2-nL sample plugs. The plate numbers obtained on the fused-silica capillary connected to the chip were about 16-25% of the predicted numbers. The conical area was removed with a flat-tipped drill bit and the band broadening was substantially eliminated (on average 98% of the predicted plate numbers were observed). All measurements were made while the device was operating with an electrospray from the end of the capillary. The effective dead volume of the flat-bottom connection is minimal and allows microfluidic devices to be connected to a wide variety of external detectors.