Demonstration of Tryptamide and its Metabolites with Solid Phase Extraction, TLC, and HPLC in Rats

Tryptamide is a compound of potent anti-inflammatory and analgesic activity. It is now under pharmacokinetic and metabolic studies in animals. We describe here a sor-bent extraction method for TLC and HPLC analysis of tryptamide and its four partially identified conjugated and non-conjugated metabolites in urine, plasma and tissue of rats. The extraction was carried out by passing the samples through pre-cleaned Amberlite XAD= 2 resin columns, washing them with saline and eluting with methanol. The conjugated metabolites were cleaved using beta-gluouronidase and sul-fatase. The HPLC separation was carried out with Lichro-sorb RP-13 and isocratic elution in three solvent systems: I, acetonitrile-water (40:60); I[, acetonitrile-water (24:76); III acetonitile-NH 4 HPO 4 (pH 2.7)06:84). Detection was accomplished with a UV detector at 254 nm.