32 

 The glass can then attract mosquitoes due to desorption of volatiles from the surface. 



The mass spectrometric detection is then desired to sample in this manner. 



Storage of samples and duration of the attraction once the sample is 



deposited on glass are also concerns. Some experiments involved collection of 



samples at a remote site with subsequent cooling in an acetone/dry ice bath to 



minimize premature desorption of volatiles. Volatile skin emanations, containing 



compounds which are attractive to mosquitoes, are amenable to cold-trapping. 



Experiments involving cold-trapping of emanations in an air stream provided, after 



reconstitution of the sample, approximately 60% attraction compared to direct 



introduction of emanations into an olfactometer [16]. 



Entomological Sampling 



Entomological work consists of determining the response of mosquitoes to 

 various cues. Samples may be pure compounds, mixtures, or skin emanations 

 transferred to a specific surface. The surface used for these experiments is glass due 

 to the ability to transfer attractants to it and subsequently desorb these attractants. 

 Experiments of this nature can be done in a laboratory controlled setting via the use 

 of an olfactometer or directly in the field. 

 Olfactometer 



The olfactometer used for measuring attraction is shown in figure 2-1 [67]. 

 The olfactometer used in these studies consists of three pairs of ports for sample 

 introduction; the figure represents only one pair of these. Each pair of ports 



