Compared to conventional bench-top instruments, microfluidic devices possess advantageous characteristics including great portability potential, reduced analysis time (minutes), and relatively inexpensive production, putting them on the forefront of modern analytical chemistry. Fabrication of these devices, however, often involves polymeric materials with less-than-ideal surface properties, spe...

Previous studies have revealed it is possible to separate a high-boiling mixture by gas chromatography in empty fused-silica capillary tubing rather than in columns coated with stationary phase. Chromatographic separation occurs solely on the basis of the different boiling points of the substances separated. The high similarity of such separations to those in classic distillation seems advantag...

1. A microrespirometer suitable for measuring oxygen uptakes from 0.1 to 10lambda per hour is described. 2. The sensitivity of the instrument may be readily altered by substituting different sizes of capillary tubing. 3. By means of replaceable brass plugs the chamber volume of this instrument may be varied from 700 to less than 40lambda. 4. No thermostat is required for the operation of the in...

The desire to make microfluidic technology more accessible to the biological research community has led to the notion of "modular microfluidics", where users can build a fluidic system using a toolkit of building blocks. This paper applies a modular approach for performing droplet-based screening, including the four integral steps of library generation, storage, mixing, and optical interrogatio...

As column volumes continue to decrease, extra-column band broadening has become an increasingly important consideration when determining column performance. Combined contributions due to the injector and connecting tubing in a capillary LC system were measured and found to be larger than expected by Taylor-Aris theory. Variance from sigma-type and tau-type broadening was isolated from eluted pe...

The performance of two capillary electrophoresis (CE) instruments, one commercial and one homemade device, were compared for the determination of derivatised aminated compounds with fluorescein isothiocyanate (FITC). The commercial CE system first uses an argon ion laser as excitation source; the homemade CE device uses an inexpensive blue-light-emitting diode (LED) as the light source and a ch...

This paper describes the first demonstration of temperature control and flow sensing of fluids using integrated circuit (IC)-based microheating elements embedded in microchannels molded in polydimethylsiloxane (PDMS). Fluid channels and connections to capillary tubing are molded in PDMS using a silicon wafer template. The PDMS film is then bonded to an IC that contains the micromachined microhe...

<b><i>Background:</i></b> Frequent blood donors are at high risk of developing iron deficiency. Currently, there is no potent screening during donation to detect deficient erythropoiesis (IDE) before anemia develops and deferral from inevitable. <b><i>Study Design Methods:</i></b> In addition capillary venous hemoglobin, the status 99 frequent was...

Several techniques have been used to treat dry eye, to irrigate the eye surface, or to apply drugs in solution. The commonest method is to apply drops. But a technique is needed for giving solutions over long periods either as drops or continuously. The apparatus described here consists of a replaceable plastic tank under mechanical pressure attached to capillary tubing which is kept in contact...