Background: Current study is aimed at designing and producing gold-nanoparticle based aptasensor for colorimetric detection of tri-nitro toluene (TNT).

Materials and Methods: Gold-nanoparticles have a wide range of application in designing biosensors for their special and highly sensitive plasmonic characteristics. In the present study, TNT molecule has been detected by designing and producing gold nanoparticle based aptasensor. After synthesizing gold nanoparticles and functionalizing them by ssDNA aptamer having 52 nucleotides, aptasensor performance for detecting target molecule was evaluated. Techniques such as dynamic light scattering (DLS), transmission electron microscope and UV-Vis spectrophotometer were used to characterize the size and shape of nanoparticles, functionalizing them by aptamer, and also their sensitivity to detect target.

Results: UV-Vis spectrophotometer, DLS, and TEM microscopy tests indicated that gold nanoparticles were synthesized with excellent quality and average size of 40 nm. TNT molecule was colorimetric detected with sensitivity of 15 nanomolar using gold nanoparticle based aptasensor.

Conclusion: According to the results it can argue that the strategy promises a novel method in detection due to wide range of such aptasensors detection. .