Determination of bupivacaine and three of its metabolites in rat urine by capillary electrophoresis

✍ Scribed by Mark A. Schieferecke; Kieran J. McLaughlin; Alexander A. Faibushevich; Professor Craig E. Lunte

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 625 KB
• Volume: 19
• Category: Article
• ISSN: 0173-0835
• DOI: 10.1002/elps.1150191633

✦ Synopsis

Determination of bupivacaine and three of its metabolites in rat urine by capillary electrophoresis

A capillary electrophoretic (CE) method for the analysis of urinary extracts of the local anesthetic, bupivacaine, and its three main metabolites, desbutylbupivacaine, 3'-hydroxybupivacaine, and 4'-hydroxybupivacaine, in rat urine has been developed. The limits of detection were 0.22 VM for desbutylbupivacaine and bupivacaine, 0.15 p~ for 3'-hydroxybupivacaine, and 0.16 p~ for 4'-hydroxybupivacaine. The linear range was from 0.7 VM to 16.8 p~ for all four compounds. Migration time and peak height reproducibilities, and extraction efficiencies were determined for all four compounds. Peak height reproducibilities (n = 5) for the overall method were improved through the use of prilocaine as an internal standard. Peak height reproducibilities were 5.6% RSD for desbutylbupivacaine and bupivacaine, and 9.9% RSD for 3'-hydroxybupivacaine and 4'-hydroxybupivacaine. Migration time reproducibilities (n = 5) were 2.4% for all compounds. Urine samples were collected from rats administered therapeutic doses of bupivacaine and extracted using a solid-phase extraction method (SPE). Separation of bupivacaine and its metabolites was achieved in 15 min.