Two different experimental approaches were employed to gain insight into the molecular interactions of nicotin e and pyridine with simple and well-characterized materials. We investigated nicotine desorption from Teflon and cotton surfaces in a flow chamber experiment and developed an ATR-FTIR spectrophotometric method to study the molecular association of pyridine with materials representative of certain indoor surfaces (cellulose and gypsum). The experimental results suggest the presence of two sorptive states for volatile amines. Spectroscopic evidence for acid-base interactions with surfaces is consistent with the observed desorption behavior.