0000000000810357
AUTHOR
W. Dünges
showing 3 related works from this author
A Universal and Sensitive Method for Gas Chromatographic Determination of Volatile Substrates and Metabolites
1978
The concentration of solutes from aqueous solutions in the μl range is still a problem in gas chromatographic trace analysis (e.g. J.S. Fritz, Acc. Chem. Res. 10, 67, 1977).
Reflux reactions for chromatography
1976
Reactions under pressure are mainly used to prepare derivatives before chromatographic analysis because of the lack of microequipment. A ml-refluxer has been designed to allow reactions under atmospheric pressure for volumes from 0.2 to 5 cm3. The reaction temperature is determined by the boiling point of the solvent thus derivatives of heat sensitive compounds can be made in the micro scale. With the aid of the ml-refluxer large series of derivatisations can be carried out and hence the reaction parameters can be optimized. This is shown at the example of the alkylation of barbituric acids for gas chromatography, where thus only N,N′-derivatives were obtained. The reliability of the appara…
Alkylation of acidic organic compounds for gas chromatographic analysis
1973
A new alkylation method is proposed. Organic solutions of fatty acids, phenols or barbituric acids are refluxed with an alkylating reagent and solid K2CO3. The reaction mixture is injected directly into the gas chromatograph. The scope of this convenient method for quantitative and qualitative analyses is considerable as different classes of alkylating agents can be used.