Design and development of electrochemical nanobiosensors based on DNA interactions

Objective: This study was carried out to design sensors modified with nanomaterials based on DNA interactions. Materials and Methods: Amorphous SiO2 nanoparticles (SiNP) were synthesized by the sol-gel method and modified onto the surface of a disposable screen-printed electrode (SPE). Electrochemical determination of the interaction of the anticancer drug Temozolomide and Patulin, a food mycotoxin, with DNA was carried out on the SiNP modified electrode surface. Results and Conclusion: It was observed that SiNP modification increased the electrode surface area by 2.3 times, from 7.5x10-4 cm2 to 17.5x10-4 cm2, and as a result, the signal increased. The stability of the developed nanosensor was tested by determining TMZ and it was observed that the nanosensor performance remained stable for 1 month and retained 70% of its performance at the end of the 2nd month. The detection limit was calculated as 5.6 µg/mL for TMZ and 7.2 µg/mL for DNA. The linear concentration range was found to be 18.6-200 µg/mL for TMZ and 23.9-80 µg/mL for DNA. The detection limit for patulin was found to be 1.15 µg/mL, and the linear concentration range was 3.2-20 µg/mL. After the interaction between PAT-dsDNA, a decrease of approximately 86% and 23% in PAT and guanine oxidation signals, respectively, was observed. It has been found that SiNP-modified SPE nanobiosensors constitute a successful alternative in DNA interaction studies by providing advantages such as low cost, speed, and practicality.