Potential sensing materials for ethanol were selected using a directed approach that focussed on the chemical nature of the target analyte (ethanol) and design constraints of the application. Using this directed approach, one polymeric material, polyaniline (PANI), was chosen as the base case, which was subsequently modified by changing the functional groups on the PANI backbone. This resulted in three potential polymeric materials: PANI, poly (o-anisidine) (PoANI), and poly (2,5-dimethyl aniline) (P25DMA). These three polymers were then doped with different metal oxide nanoparticles: aluminum oxide (Al­₂O₃), copper oxide (CuO), nickel oxide (NiO), titanium dioxide (TiO₂), and zinc oxide (ZnO). In total, twenty-six potential polymeric and nanocomposite sensing materials were evaluated for their sensitivity and selectivity to ethanol, with respect to methanol, acetone, and benzene, as typical interferents. Of these potential sensing materials, four polymeric nanocomposites had the required high sensitivity and selectivity towards ethanol for the application (transdermal ethanol detection).