Figure 1. A typical commercial capillary zone electrophoresis system (not drawn to scale). The extremities of the capillary are immersed in small vials containing the background electrolyte and two platinum wires connected to a high-voltage power supply that can deliver up to 30000 V. The detector, placed close to one extremity of the capillary, can be either an ultraviolet/visible system (provided with filters or a monochromator) or a diode array detector. Some instruments are provided with a laser-induced fluorescence detector. The carousel for sample loading and the computer that controls the whole unit are not shown. EOF: electroendoosmotic flow.

Figure 2. Capillary zone electrophoresis of the 39 PCR-amplified fragment in 50 mm phosphate buffer in the presence of 7 m urea (apparent pH of 3.0). Conditions were Bio Rad Bio Focus 3000; capillary length, 40 cm; inner diameter, 50 m; injection, 5 s at 10 kV. Separations were done at 150 V cm^–1 at 25°C. (a) Control, wild-type 39; (b) 39 from heterozygous individual. Note the full resolution between the wild-type and mutant strands in (b). (Reproduced with permission from Gelfi et al., 2000b.)

Figure 3. Capillary zone electrophoresis of tryptic digests of -casein. (a) Conditions were: inner diameter, 100 m; capillary length, 37 cm; electrolyte, 80 mm phosphate buffer (pH 2.0). Separations were done at 110 V cm^–1 (current 85 A) and detection was at 214 nm. The three main peaks are fragment -CN (114–169), pI 6.1; fragment -CN (49–97), pI 6.93; and fragment -CN (33–48), pI 3.95. (b) Conditions were: inner diameter, 100 m; capillary length, 37 cm; bath, 50 mm isoelectric aspartic acid (pH roughly the pI value of 2.77) with 0.5% hydroxyethyl cellulose and 5% trifluoroethanol. Separations were done at 600 V cm^–1 (current 58 A). (Reproduced with permission from Righetti et al. (2000).)