Quantitative gas chromatographic analysis of plant cuticular waxes containing long-chain aldehydes

Abstract

The gas chromatographic quantification of long-chain aldehydes occurring in the cuticular waxes of numerous plant species is often non-reproducible when silylating or methylating derivatization reagents are applied. It is shown that, depending on reaction conditions, more than 50% of the aldehydes present in a sample may be lost when total wax extracts are analysed after silylation. A method involving the separation of the sample into two fractions by a simple solid phase extraction step has been developed. The fraction containing the long-chain aldehydes can be analysed without derivatization. Extensive tests using analytical standards and authentic wax samples demonstrated that this method (applicable to sample sizes in the range from 0.2–0.5 mg of wax) allows for the quantitative and reproducible analysis of long-chain aldehydes. © 1998 John Wiley & Sons, Ltd.