摘要 |
The separations resulting from capillary electrophoresis performed in a microbore capillary tube (35) are detected on-line by focusing a light beam (63) in the form of a line or sheet of light (63) on the capillary passage (36) in which the separations (55a-c) take place so that the width of the sheet of light encompasses the length of the passage in which separations of interest are expected to take place. The separations form concentration gradients (16) in the capillary passage (36) encompassed by the light beam and cause refraction of portions of the light beam and variations in the intensity of the light beam due to such refraction. Alternately, the separated components (55a-d) may absorb light of certain frequencies so if the light beam includes light of the certain frequencies, variation in the intensity of the light beam is caused by such absorbance. The variation in the intensity of light along the width of the light beam after passage through the sample (125) is sensed and is indicative of the concentration gradients (160, 161). By using a reagent (125) which reacts with an analyte not having an isoelectric point to form a product having an isoelectric point (100, 101), such analyte may be detected and measured by isoelectric focusing techniques. |