An engineered egg is placed in a voltage clamp system and an odorant is dissolved in the buffer solution in which the egg is floating.
"The chief source of methane is natural gas, but it can also be produced from coal. Abundant, cheap, and clean, methane is used widely as a fuel in homes, commercial establishments, and factories; as a safety measure, it is mixed with trace amounts of an odorant to allow its detection."
In this paper, the gene of general odorant binding protein 2 in the antenna of Helicoverpa assulta (Guen?)was cloned and expressed in Escherichia coli.
(2) sorption of odorant molecules into the mucus at the air mucus interface;