In situ continuous derivatization/pre-concentration of carbonyl compounds with 2,4-dinitrophenylhydrazine in aqueous samples by solid-phase extraction Application to liquid chromatography determination of aldehydes.
A rapid and straightforward continuous solid-phase extraction system has been developed for in situ derivatization and pre-concentration of carbonyl compounds in aqueous samples. Initially 2,4-dinitrophenylhydrazine, the derivatizing agent, was adsorbed on a C(18) mini-column and then 15-ml of sample were continuously aspirated into the flow system, where the derivatization and pre-concentration of the analytes (low-molecular mass aldehydes) were performed simultaneously. Following elution, 20 microl of the extract were injected into a LC-DAD system, in which hydrazones were successfully separated in 12 min on a RP-C(18) column using a linear gradient mobile phase of acetonitrile-water of 60-100% acetonitrile for 8 min, flowing at 0.5 ml/min. The whole analytical process can be accomplished within ca. 35 min. Under optimum conditions, limits of detection were obtained between 0.3 and 1.0 microg/l and RSDs (inter-day precision) from 1.2 to 4.6%. Finally, some applications on water samples are presented with recoveries ranged from 95.8 to 99.4%.
Baños
Clara-Eugenia
CE
Department of Analytical Chemistry, Marie-Curie Building (Annex), Campus of Rabanales, University of Córdoba, E-14071 Córdoba, Spain.
Silva
Manuel
M
D000447:Aldehydes / Q000302:isolation & purification*; D002853:Chromatography, Liquid / Q000379:methods; D006834:Hydrazines / Q000737:chemistry*; D006835:Hydrazones / Q000737:chemistry; D052616:Solid Phase Extraction / Q000379:methods*; D018508:Water Purification / Q000379:methods
D000447:Aldehydes; D006834:Hydrazines; D006835:Hydrazones; C446799:dinitrophenylhydrazine