A comparative study of several HPLC methods for determining free amino acid profiles in honey.
A study of the viability of three derivatizing reagents for obtaining amino acid profiles in honey through high performance liquid chromatography (HPLC) is presented. A method using diode array detection based on a reaction with diethyl ethoxymethylene malonate (DEMM) and two other methods using fluorescence detection based on derivatization with fluorenylmethyl chloroformate (FMOC-Cl) and 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) have been developed. The three methods yield detection limits close to the ppb level, but vary in relation to other analytical characteristics. The use of methyl chloroformate derivatives allows the profile to be obtained with the greatest sensitivity within a short time frame. On applying such methods to honey samples of diverse botanical origin, we observe that the proline values obtained are always lower than those found using the official spectrophotometric method, thereby underlining the advisability of using HPLC methods to reduce uncertainty in these results.
Bernal
José Luis
JL
Department of Analytical Chemistry, Faculty of Sciences, University of Valladolid, Valladolid E-47005, Spain. jlbernal@qa.uva.es
Nozal
María Jesús
MJ
Toribio
Laura
L
Diego
Juan Carlos
JC
Ruiz
Antonio
A
D000596:Amino Acids / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006722:Honey / Q000032:analysis*; D012680:Sensitivity and Specificity
D000596:Amino Acids