The template assisted electrochemical deposition technique was used for the synthesis of gold nanotubes
array (AuNTsA). The morphological structure of the synthesized AuNTsA was observed by scanning
electron microscopy and found that the individual nanotubes are around 1.5 μm in length with a diameter
of 200 nm. Nanotubes are vertically aligned to the Au thick film, which is formed during the
synthesis process of nanotubes. The electrochemical performance of the AuNTsA was compared with the
bare Au electrode and found that AuNTsA has better electron transfer surface than bare Au electrode
which is due to the high surface area. Hence, the AuNTsA was used as an electrode for the fabrication of
DNA hybridization biosensor for detection of Mycobacterium Tuberculosis DNA. The DNA hybridization
biosensor constructed by AuNTsA electrode was characterized by cyclic voltammetry technique with Fe
(CN)6
3/4 as an electrochemical redox indicator. The selectivity of the fabricated biosensor was illustrated
by hybridization with complementary DNA and non-complementary DNA with probe DNA immobilized
AuNTsA electrode using methylene blue as a hybridization indicator. The developed electrochemical
DNA biosensor shows good linear range of complementary DNA concentration from 0.01 ng/μL
to 100 ng/μL with high detection limit.