MICROFLUIDIC DEVICES CONNECTED TO CAPILLARIES WITH MINIMAL DEAD VOLUME

摘要

A method is provided for joining a microchip device to a capillary tube. Themicrochip device has a capillary channel opening onto an edge surface of thedevice. A short hole is drilled into the edge surface, aligned with thecapillary channel. The drilling is done with a flat bottom, preferably by atwo-step drilling process. Then, the end of the capillary can be inserted intothe hole so that its end is substantially flush with the flat bottom of thehole, thereby eliminating dead volume. Testing has shown that this connectionprovides very little band broadening of samples transported through thecapillary channel into the capillary tube. The tip of the capillary tube canbe tapered, so that it is suitable for use as an electrospray source for amass spectrometer.