A gas sensor characterized in that the gas sensor has at least:. Certain of these compounds also inhibit leukocyte adhesion and, in particular, leukocyte adhesion mediated by VLA-4. The transistors are exposed to a nitridation ambient which, due to their differences in sizing, results in nitridizing the tunnel oxide in its entirely but only partially nitridizing the gate oxide. A second device is arranged and adapted to apply one or more transient DC voltages to the spiral electrodes in order to urge ions towards the first end of the ion mobility separator or spectrometer.