A green impedimetric aptasensor for non-invasive and high-selective detection of tramadol validated by molecular dynamic simulation.

Although the dosage controlling of tramadol (TRA) as a banned deadly drug in human biofluids is medicolegally important a biocompatible method for its high-selective detection with fewer false interferences has been scarcely reported. Herein, a new impedimetric aptasensor is introduced by utilizing the aptamer (Apt) sequence with high affinity to TRA for the first time to non-invasively measure it. An oriented nanolayer of Au nanoparticles (AuNPs) is easily formed on the surface by the electrodeposition technique to high-densely load the Apt and embed the novel aptasensing interface via a user-friendly methodology. The visual interaction of Apt with its target has been explored using molecular dynamic (MD) simulation to confirm how Apt traps TRA in its arm. The aptasensor measured TRA in a concentration range of 50 pM to 1.3 nM with a limit of detection (LOD) of 16.66 pM in buffer. It also rendered good accuracy and recovery for human salivary and urinary analysis. In addition, the greenness profile of the proposed methodology has been validated with two international common indexes. The developed aptasensor promises a reasonable capability for TRA monitoring in real clinical or street narcotic samples according to green analytical chemistry (GAC).