2-4-dinitrophenylhydrazine and benzaldehyde

Topics: Acetaldehyde; Benzaldehydes; Enzyme Activation; Hydrazones; Monoamine Oxidase; Monoamine Oxidase Inhibitors; Phenylhydrazines; Protein Binding; Spectrophotometry

A simple and high collection efficiency sampling method was developed for the monitoring of carbonyl compounds, i.e., formaldehyde, acetaldehyde, benzaldehyde, acetone and butanone. The determination is based on the reaction of these compounds in a sensitive absorbing solution of 2,4-DNPH. After the completion of the reaction the derivatives were analyzed by the HPLC system without any post sample preparation. The operation conditions of the proposed method were optimized to obtain the highest sampling efficiency within a short analysis time. The collection efficiency for all compounds was in the range of 95 ± 3 % to 99 ± 4 % and the relative standard deviations (n = 15) were less than 10 %. This method was validated and applied to monitor carbonyl compounds in air samples from an occupational environment, the adhesive industry. Formaldehyde was found to be the most abundant carbonyl compound (64 ± 8 to 250 ± 20 ppbv), followed by acetaldehyde (ND to 24 ± 6 ppbv), acetone (ND to 21 ± 5 ppbv) and benzaldehyde (ND to 27 ± 7 ppbv). The sampling of air directly into the absorbing solution was compared with the conventional method of using an adsorbent cartridge, and the results were in good agreement (P > 0.05).

Topics: Acetaldehyde; Acetone; Air Pollutants; Benzaldehydes; Butanones; Chromatography, High Pressure Liquid; Environmental Monitoring; Formaldehyde; Industry; Phenylhydrazines; Reproducibility of Results; Specimen Handling; Temperature; Time Factors; Volatile Organic Compounds; Workplace

A simple and rapid method has been reported for the determination of carbonyl compounds involving reaction with 2,4-dinitrophenylhydrazine and extraction of hydrazones with water-miscible organic solvent acetonitrile when the phase separation occurs by addition of ammonium sulphate, a process called salt-assisted liquid-liquid microextraction. The extract was analyzed by high-performance liquid chromatography with UV detection at 360 nm. The procedure has been optimized with respect to solvent suitable for extraction, salt for phase separation between water and organic solvent, reaction temperature and reaction time. The method has been validated when a linear dynamic range was obtained between the amount of analyte and peak area of hydrazones in the range 7 microg-15 mg L(-1), the correlation coefficient over 0.9964-0.9991, and the limit of detection in the range 0.58-3.2 microg L(-1). Spiked water samples have been analyzed with adequate accuracy, and application of the method has been demonstrated in the analysis of benzaldehyde formed as oxidation product in pharmaceutical preparation where benzyl alcohol is used as preservative, and for a keto drug dexketoprofen.

Topics: Aldehydes; Benzaldehydes; Chemical Fractionation; Chromatography, High Pressure Liquid; Cyclohexanones; Fresh Water; Ketones; Ketoprofen; Molecular Structure; Organic Chemicals; Pharmaceutical Preparations; Phenylhydrazines; Reproducibility of Results; Solvents; Tromethamine; Water; Water Pollutants, Chemical