Development and Validation of an LC-UV Method for Quantitation of 4-Bromo-2,5-Dimethoxyamphetamine (DOB), 4-Bromo-2,5-Dimethoxyphenetylamine (2C-B), Methylphenidate, Fenproporex and Amfepramone

A sensitive and reliable isocratic LC-UV method was developed and validated for quantification of 4-bromo-2,5-dimethoxyamphetamine (DOB), 4-bromo-2,5-dimethoxyphenetylamine (2C-B), amfepramone (diethylpropione, DEP), fenproporex (FEN) and methylphenidate (MPH). Although these substances are not usually associated, the fact that the same method could be used to analyze five different amphetamines would be very helpful in forensic analysis. The validation parameters accessed were linearity, specificity, precision, accuracy, limit of detection, limit of quantification and robustness. During the evaluation of selectivity, benzaldehyde (BZ) and N-methyl-diethanolamine (MDEA), two out of nine related substances tested, did not show good resolution from DOB and FEN, respectively. However, commercial preparations containing DEP, FEN and MPH were analyzed and no interference from their excipients was noticed. Through this method, these five amphetamine derivatives studied were simultaneously identified and quantified. The developed method is easy to implement, fast and suitable for use in routine laboratory analysis. The only limitation would be the quantitation of DOB and FEN in the presence of large amounts of BZ and MDEA, respectively.