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The aim of this study was to use headspace solid phase microextraction (SPME) to reveal the presence of resin in archaeological samples, such as mummification balms, from ancient Egypt. Experiments were first performed with fresh resins of known origin. The SPME fibre readily extracted mono- and sesquiterpenes and, to a lesser extent, diterpenes. Using mass spectra and retention indices of constitutive compounds, qualitative analysis of the volatile fraction allowed us to differentiate resins or gum-resins such as myrrh, olibanum, galbanum, labdanum, mastic, and conifer resins. SPME was then successfully applied to archaeological samples from ancient Egypt in which the presence of resins was detected. Volatile components were desorbed and trapped according to the same SPME procedure as was applied to fresh resins, after a sample preparation consisting of a fine grinding.

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19 F NMR is used for monitoring the in vitro behaviour in locust organs or tissues of an ester with a fluorinated alkoxy structure and a chiral acyl moiety. In carrying out analysis directly in the biological media, the problematic extraction of polar metabolites is avoided, contributing to an easier and more reliable monitoring. Thus, in diluted haemolymph a remarkable enantioselectivity of the transformation is evidenced. Over a four hour period the ester R remains unalterated, while the S enantiomer is completely hydrolyzed. This enantioselectivity is the reverse of the trend which is generally observed in the hydrolysis of esters by lipases.