This study employed density functional theory (DFT) to investigate the adsorption of lung cancer biomarkers in exhaled breath on polyaramid monolayer (2DPA). Specifically, we focused on P-cresol, propanol, acetone, hexanal, nonanal, formaldehyde, and benzene. Furthermore, an examination has conducted to ascertain the most stable configurations of desired biomarkers on the 2DPA substrate. The adsorption energies for the complexes P-cresol/2DPA, propanol/2DPA, acetone/2DPA, hexanal/2DPA, nonanal/2DPA, formaldehyde/2DPA, and benzene/2DPA were calculated to be −0.90, −0.86, −0.83, −0.82, −0.74, −0.56, and − 0.51 eV, respectively. The Hirshfeld charge transfers for the biomarker molecules in their respective complexes with 2DPA P-cresol, propanol, acetone, hexanal, nonanal, formaldehyde, and benzene are 0.02, 0.08, 0.05, 0.02, 0.39, 0.04, and 0.02 electrons, respectively. In addition to examining the target lung cancer biomarkers, the study also investigated the adsorption behavior of four common interfering molecules found in exhaled human breath: nitrogen (N₂), oxygen (O₂), carbon dioxide (CO₂), and water (H₂O). This comparative analysis provided valuable insights into the selectivity of the polyaramid monolayer (2DPA) as a sensing platform and highlighted potential interferences that may arise during its use. The 2DPA used in this study exhibited unique electronic properties and ϕ-type sensor characteristics on its surface. These features allow for the detection of specific lung cancer biomarkers, including P-cresol, hexanal, and nonanal, which were the primary focus of this investigation. Furthermore, the 2DPA monolayer demonstrates suitable adsorption energy, significant changes in electronic attributes, and appropriate recovery time when exposed to P-cresol, propanol, acetone, and hexanal biomarkers. Accordingly, this sensor may be regarded as a device for the expeditious recognition of lung cancer by analyzing exhaled breath, thereby facilitating early treatment and improving patient outcomes.
