Abstract: Microfluidic devices provide substances to a mass spectrometer. The microfluidic devices include first and second surfaces, at least one microchannel formed by the surfaces, and an outlet at an edge of the surfaces which is recessed back from an adjacent portion of the edge. Hydrophilic surfaces and/or hydrophobic surfaces guide substances out of the outlet. A source of electrical potential can help move substances through the microchannel, separate substances and/or provide electrospray ionization.

Abstract: Microfluidic devices provide substances to a mass spectrometer. The microfluidic devices include first and second surfaces, at least one microchannel formed by the surfaces, and an outlet at an edge of the surfaces. Some embodiments also include a tip surface with one or more surface features for helping guide substances from the outlet of the device toward a mass spectrometer. In some embodiments, the surface feature(s) includes a groove, which may be hydrophilic along all or part of its length. Hydrophilic surfaces and/or hydrophobic surfaces may also help guide substances out of the outlet and/or toward the mass spectrometer. In some embodiments, the outlet and/or the tip surface is recessed back from an adjacent portion of the edge. A source of electrical potential can help move substances through the microchannel, separate substances and/or provide electrospray ionization.

Abstract: Microfluidic devices provide substances to a mass spectrometer. The microfluidic devices include first and second surfaces, at least one microchannel formed by the surfaces, and an outlet at an edge of the surfaces which is recessed back from an adjacent portion of the edge. Hydrophilic surfaces and/or hydrophobic surfaces guide substances out of the outlet. A source of electrical potential can help move substances through the microchannel, separate substances and/or provide electrospray ionization.

Abstract: A method of fabricating a micromachine includes the step of constructing a low surface energy film on the micromachine. The micromachine is then rinsed with a rinse liquid that has a high surface energy, relative to the low surface energy film, to produce a contact angle of greater than 90.degree. between the low surface energy film and the rinse liquid. This relatively large contact angle causes any rinse liquid on the micromachine to be displaced from the micromachine when the micromachine is removed from the rinse liquid. In other words, the micromachine is dried by dewetting from a liquid-based process. Thus, a separate evaporative drying step is not required, as the micromachine is removed from the liquid-based process in a dry state. The relatively large contact angle also operates to prevent attractive capillary forces between micromachine components, thereby preventing contact and adhesion between adjacent microstructure surfaces.