Electrochemical genosensor based on template assisted synthesized polyaniline nanotubes for chronic myelogenous leukemia detection.

This work reports a facile approach to synthesize polyaniline nanotubes (PANI-NT) by using manganese oxide as sacrificial templates. This template assisted polyaniline nanotubes (t-PANI-NT) were utilized as electrode material after deposition onto the indium tin oxide (ITO) coated glass substrates by using the electrophoretic technique. The structural, morphological and electrochemical characterizations of the t-PANI-NT show relatively better results compared to chemically synthesized PANI-NT (c-PANI-NT). Moreover, the t-PANI-NT/ITO electrode exhibits improved electron transfer coefficient (α = 0.63) and charge transfer rate constant (ks = 0.05912 s-1) in comparison to c-PANI-NT/ITO electrode (α = 0.56 and ks = 0.06548 s-1). The obtained t-PANI-NT/ITO electrodes have been further immobilized with biotinylated DNA sequence, specific to chronic myelogenous leukemia (CML) by using avidin-biotin as a cross-linking agent. Electrochemical impedance spectroscopy studies revealed that the genosensor displays linearity in wide range of target DNA concentration (10-6 to 10-16 M) with an outstanding differentiation ability and low detection limit of 10-16 M. The experimental results of this highly sensitive and specific genosensor with clinical samples of CML positive patients and control negative patients indicate its potential for clinical diagnostics.