Journal of Chromatography, 403 ( 1987) 47-6 1 Elsevier Science Publishers B.V., Amsterdam - Printed in The Netherlands CHROM. 19 645 CARRIER-FREE ZONE ELECTROPHORESIS, DISPLACEMENT ELECTRO- PHORESIS AND ISOELECTRIC FOCUSING IN A HIGH-PERFORMANCE ELECTROPHORESIS APPARATUS STELLAN HJERTEN*, KARIN ELENBRING. FERENC KILAR* and JIA-LI LIAO** Institute zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA qf Biochemistry, University of C’ppsalu, Biomedical Centre, P.O. Box 576. S-751 23 Uppsala (Swe- den) and ALBERT J. C. CHEN, CHRISTOPHER J. SIEBERT and MING-DE ZHU*** Bio-Rad Laboratories, 1414 Harbor Way South, Richmond, CA 94801 !U.S.A.) (Received April 22nd, 1987) SUMMARY A characteristic feature of high-performance electrophoresis (HPE), the elec- trophoretic counterpart of high-performance liquid chromatography (HPLC), is that the separation chamber is a thin-walled, narrow-bore (0.05-0.3 mm) glass or fused- silica capillary tube for rapid dissipation of the Joule heat in order to minimize thermal zone deformation even at high field strengths. This paper is centered around the usefulness of HPE for separation in a carrier-free medium (i.e., in buffer alone) and deals with both zone electrophoresis, isoelectric focusing and displacement elec- trophoresis. Examples are given of analytical and micropreparative separations of inorganic and organic ions, proteins, viruses and bacteria. The run times are 5-30 min. Discontinuous buffer systems have up to now been used exclusively for the separation of proteins by electrophoresis in polyacrylamide gels (“disc electropho- resis”). However, the Ornstein and Davis discontinuous buffer system has been modi- fied to adapt it to carrier-free zone electrophoresis in order to achieve automatic sharpening of the starting zone. Very high resolution of serum proteins was obtained when they were subjected to free high-performance disc electrophoresis in such a modified buffer system. To show that the HPE apparatus permits electrophoresis also in a gel medium, a polyacrylamide electrophoresis in SDS is presented. This experiment illustrates the difference between electropherograms obtained zyxwvutsrqponmlkjihgfedcbaZYXWVUTSR in free solution and- in a molecular- sieving medium. * Permanent address: Department of Neurology and Psychiatry, University of Pks, Medical School, P&s, Hungary. * Permanent address: Biology Department, Jinan University, Guangzhou, China. *** Permanent address: Central Laboratory, Academy of Traditional Chinese Medicine, Beijing, China. 0021-9673/8?/$03.50 (0 1987 Elsevier Science Publishers BV