CHAPTER 1 

 INTRODUCTION 



Research Objectives 



The primary goal of this work is to provide a better understanding of the 

 chemical basis for the attraction of mosquitoes to human hosts. Novel studies and 

 approaches were conducted in three areas to meet this goal. The first objective is 

 to determine the best method of sample introduction for analysis. The decision 

 involves balancing sensitivity, resolution, as well as selectivity. Here, selectivity 

 implies sampling in a manner similar to that in which mosquitoes are exposed, i.e. 

 a volatile sample in the gas phase. The second objective of this work is to determine 

 methods to alter attraction. Studies involving changing the matrix conditions of a 

 sample and the effect on attraction will be addressed. The third objective is to 

 determine compounds which emanate from the skin. This objective is closely linked 

 to sampling in that the sampling method ultimately determines how many and which 

 compounds are detected. An important component of this objective is to 

 differentiate between unattractive and attractive components which emanate from 

 the skin. This has been approached by case studies involving the comparison of skin 

 emanations between hosts who differ in attraction to mosquitoes and by monitoring 



