For the rapid and sensitive analysis of proteins, and to obtain reproducible results, an apparatus for isotachophoresis, Shimadzu IP-2A, was modified and the electrophoretic conditions were standardized. The apparatus was modified as follows; 1) Two peristaltic pumps were used instead of N
2 gas pressure system, for rinsing and refilling the capillary tube and the electrode chambers. 2) The flow lines were simplified into 3 lines, instead of 10 lines of the commercial apparatus. The electrophoretic conditions were changed as follows; 1) Hexane was overlayed on the electrolyte solutions to minimize the solubilization of CO
2, instead of the use of Ba(OH)
2. 2) The inner surface of the capillary tube was coated with hydroxypropyl methyl cellulose (HPMC), instead of using HPMC-containing leading electrolyte. The amount of the ampholyte mixture (Ampholine pH 3.5-10) to be applied was standardized to be 20μg. From these improvements and standardization, the interruption of electrophoresis by N
2 gas bubbles or by the precipitation of BaCO
3 were avoided and the procedure of isotachophoretic analysis was simplified. Serum proteins as low as 3μg could be separated into 20 UV-absorbing peaks within 16min of running time in good reproducibility.
抄録全体を表示