CHAPTERS 

 IDENTIFICATION OF SKIN EMANATIONS 



Introduction 



This chapter addresses issues concerning emanations from the skin. The 

 practical aspects of CI and EI analyses, as they pertain to this work, will be 

 presented in this section. The results cover the qualitative identification of 

 components which are detectable via desorption from handled glass beads. Two case 

 studies are presented involving human subjects. The first study compares differences 

 in the mass spectra of two human subjects who differ significantly in their attraction 

 of mosquitoes. The second case study will compare results obtained from the mass 

 spectra of handled beads to the attraction reported by bio-assay in an olfactometer 

 for samples collected on different days from the same human subject. 



Sample Introduction and Separation 



The concerns regarding sample introduction were partially addressed in 

 Chapters 1 and 2. The most important criterion was detection with as little sample 

 modification as possible, mimicking the response of mosquito chemosensilla to 

 volatilized compounds. Due to this principle, methods involving dissolution of 

 emanations into solvents were avoided; this limited the possibility of discriminating 



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