Quantitative response in ion mobility spectrometry with atmospheric pressure chemical ionization in positive polarity as a function of moisture and temperature.

Response of an ion mobility spectrometer at ambient pressure was quantitatively determined for fourteen chemicals from five chemical families spanning a range of proton affinities and temperature from 30 to 175 °C with moisture from 1 to 1 × 10 ppm in purified air. Peak intensities, drift times and reduced mobility coefficients were determined for hydrated protons from aNi ion source and for protonated monomers and proton bound dimers of alcohols, aldehydes, acetates, ketones, and organophosphates. These measurements permitted the determination of response factors with atmospheric pressure chemical ionization and the influence of moisture and temperature on APCI response with correlation to computational models of hydration values.