Monitoring the electroosmotic flow in capillary electrophoresis using contactless conductivity detection and thermal marks.

The fundamental aspects and the capillary electrophoresis usage of thermal marks are presented. The so-called thermal mark is a perturbation of the electrolyte concentration generated by a punctual heating of the capillary while the separation electric field is maintained. The heating pulse is obtained by powering tungsten filaments or surface mount device resistors with 5 V during a few tens to hundreds of milliseconds.

Extending the lifetime of the running electrolyte in capillary electrophoresis by using additional compartments for external electrolysis.

The use of two additional reservoirs to accommodate the electrodes of the power source is proposed to improve the stability of the running electrolyte in capillary electrophoresis. The basic idea is to use salt bridges to connect those reservoirs to the ones containing the capillary ends. Although simple, there are several issues that can be considered in the design and implementation of such system in order to prevent undesired transference of material between the electrolysis and the main reservoirs.

A dry process for production of microfluidic devices based on the lamination of laser-printed polyester films.

A new microfabrication process based on a xerographic process is described. A laser printer is used to selectively deposit toner on a polyester film, which is subsequently laminated against another polyester film. The toner layer binds the two polyester films and allows the blank regions to become channels for microfluidics.