2-4-dinitrophenylhydrazine and methylethyl-ketone

A new continuous-flow gradient-elution micellar electrokinetic capillary chromatography method is developed for the determination of airborne carbonyls after derivatization with 2,4-dinitrophenylhydrazine. A total of 16 carbonyls can be determined with detection limits ranging from 0.94 to 8.50 mg/L, working range from 4.72 to 346 mg/L, and repeatabilities (relative standard deviation, n=5) from 1.23 to 4.6% or 3.93 to 7.6% for migration time and peak area, respectively. Coupling with denuder-filter sampling, a preliminary survey has been conducted to determine gaseous and particulate carbonyls from air sampled at a roadside station. The method is shown to have sufficient sensitivity for 1-h sampling of ambient carbonyls with detection limits ranging from 0.045 to 1.2 microg/m3 and working range from 0.11 to 43.3 microg/m3 at a flow rate of 10 Lpm. The method requires minimal modification of commercially available capillary electrophoresis equipment and can differentiate gaseous and particulate carbonyls to provide essential information and objective data for adopting effective measures to combat the discharge of carbonyl compounds to the atmosphere.

Topics: Acetone; Air Pollutants; Aldehydes; Butanones; Chromatography, Micellar Electrokinetic Capillary; Gases; Hong Kong; Particulate Matter; Phenylhydrazines

The 2,4-dinitrophenylhydrazine (2,4-DNPH) derivatization method mainly used for the determination of airborne formaldehyde was extended for acetaldehyde, acetone, 2-butanone, and cyclohexanone, the next four carbonyl compounds of industrial importance. Sampling devices and sampling conditions were adjusted for the respective limit value regulations. Analytical reliability criteria were established and compared to those of other recommended methods. With a minimum analytical range from one tenth to the 3-fold limit value in all cases and with relative standard deviations below 5%, the adjusted method meets all requirements for the reliable quantification of the four compounds in workplace air as well as in ambient air.

Topics: Acetaldehyde; Air Pollutants; Butanones; Calibration; Chromatography, High Pressure Liquid; Cyclohexanones; Phenylhydrazines; Reproducibility of Results; Sensitivity and Specificity

This noninvasive method for collection and analysis of a wide range of aldehydes and ketones in human breath may enable assessment of lipid peroxidation and metabolic status in vivo. Breath samples are drawn through silica cartridges impregnated with 2,4-dinitrophenylhydrazine, which traps carbonyls as their hydrazone derivatives. The hydrazone derivatives are eluted from the cartridges with acetonitrile, separated by reversed-phase HPLC, and quantified spectrophotometrically. Using this method, we have measured formaldehyde, acetaldehyde, acetone, propanal, 2-butanone, butanal, pentanal, and hexanal. Recoveries of carbonyls added to Douglas bags were > 90%, except for 2-butanone, which was 86.2%. The overall CVs for sampling plus analyzing duplicate aliquots of breath were < 11%. The results indicate that this protocol can be used to monitor changes of carbonyl production by analyzing expired air, which may, with further study, indicate physiological and pathological status.

Topics: Acetaldehyde; Acetone; Aldehydes; Breath Tests; Butanones; Chromatography, High Pressure Liquid; Formaldehyde; Humans; Hydrazones; Ketones; Phenylhydrazines; Specimen Handling; Volatilization