The adsorption of NOx (NO2/N2O4) gas on a Langmuir-Blodgett (LB) monolayer film of terbium bisphthalocyanine (TbPc(2)) was studied. The LB film was fabricated onto an interdigitated gold electrode, and the adsorption-desorption process was monitored by the change in electrical conductivity during gas exposure. The kinetics of the gas adsorption and desorption processes, as well as the reversibility of the response, were studied as a function of temperature (293-398 K). The data can be rationalized in terms of the Temkin isotherm, and the activation energy for the process was in agreement with those reported for crystals and thick films.