An iridium oxide nanoparticle and polythionine thin film based platform for sensitive Leishmania DNA detection

An impedimetric label-free genosensor for high sensitive DNA detection is developed. This system is based on a screen-printed carbon electrode modified with the thionine layer and iridium oxide nanoparticles (IrO₂ NP). An aminated oligonucleotide probe is immobilized on the IrO₂ NP/polythionine modified electrode and ethanolamine was used as a blocking agent. Different diluted PCR amplified DNA samples have been detected. The selectivity and reproducibility of this system are studied and the system was highly reproducible with RSD ≈ 15% and sensitive enough while using 2% of ethanolamine during the blocking step employed for genosensor preparation.