Sprayer for quantitative application of odor stimuli

ABSTRACT A novel device is described for the quantitative application of chemical stimuli. Thedevice uses ultrasound to disperse a solution of volatile chemicals as an aerosol. A motor-drivensyringe controls the rate at which the solution is released from a glass capillary. Vibration of thecapillarydispersesthereleasedsolutionintomicrodropletsthatevaporatecompletelywithinafewcentimeters of the tip. The ratio of chemical stimulus to solvent is maintained until the liquid isdispersedandthereforethereleaserateofthechemicalstimuluscanbesetandcalculatedstraight-forwardly from the dilution factor and the dynamically controllable speed of the syringe plunger.Thesprayerpermitsthedeliveryofchemicalstimulusindependentofrelativevaporpressuresofthecomponents and of environmental factors such as temperature. The sprayer is easy to operate, canbeconstructedfrominexpensivematerials,andcanbeusedtoemitodorstimuliinthewindtunnelor any other bioassay for pheromones and plant volatiles. KEYWORDS pheromones,plantvolatiles,odorquantiÞcation,ultrasound,releaserate,olfactorystimulation