High-performance liquid chromatographic determination of N1-alkylnicotinamide in urine

✍ Scribed by Teruhisa Hirayama; Koichi Yoshida; Kazuhiko Uda; Motoshi Nohara; Shozo Fukui

• Publisher: Elsevier Science
• Year: 1985
• Tongue: English
• Weight: 481 KB
• Volume: 147
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(85)90015-6

✦ Synopsis

A simple high-performance liquid chromatographic method has been developed for determining N1-alkylnicotinamides, including C1-C5 alkyl derivatives, in urine. N1-Alkylnicotinamides were reacted with acetophenone in strong alkali medium at 0 degrees C and then formic acid was added. The reaction mixture was heated in acidic medium at above 93 degrees C, and the fluorescent product, 1-alkyl-7-phenyl-1,5-dihydro-5-oxo-1,6-naphthyridine, was chromatographed by HPLC, using a Zorbax SCX-300 column with a mixed mobile phase of acetonitrile-0.04 M ammonium phosphate, monobasic. N1-Alkylnicotinamides can be determined as 1,6-naphthyridine derivatives by a fluorometric detector at a level of 100 pg (signal/noise = 2). Recoveries of N1-alkylnicotinamides in urine were satisfactory. Interfering reaction products from NAD+ and NADP+ were clearly eliminated for determination of N1-alkylnicotinamides without pentyl derivatives.