[Rapid separation and determination of enterotoxigenic E. coli by capillary zone electrophoresis]

Rapid separation and determination of enterotoxigenic E. coli K88, K99 and 987P with intact cells using capillary zone electrophoresis (CZE) are described. The CZE was performed in a running buffer of 0.05 mol/L Na2CO3-NaHCO3 (pH 9.9), under applied voltage of 14.1 kV and detected by an on-line UV at 210 nm. Results show that K88, K99 and 987P were separated completely. Moreover, each strain presented a characteristic peak and a reproducible retention time (RSD < or = 0.9%). The successful analysis of enterotoxigenic E. coli in the excrement of diarrhea piglets is also discussed. K88 and K99 were detected in the excrement of diarrhea piglets born in 5 d - 6 d, and 30 d - 35 d respectively, and nothing was detected in the excrement of diarrhea piglets born in about 60 d.