Nanostructured zirconium oxide based genosensor for Escherichia coli detection

A deoxyribonucleic acid (DNA) biosensor has been fabricated via immobilization of 17 base terminal single stranded DNA (ssDNA) identified from the 16s rRNA coding region of Escherichia coli onto sol–gel derived nanostructured zirconium oxide (NanoZrO2) film. An oligonucleotide probe with a terminal 5′-phosphate group has been attached to the surface of the electrode via affinity of NanoZrO2 for phosphate. The results of hybridization studies carried out with the complementary, non-complementary and genomic DNA reveal that ssDNA/NanoZrO2/ITO bioelectrode has a high selectivity and sensitivity towards hybridization detection with limits of 10−6–106 pM of complementary DNA.