A novel label free electrochemical aptasensor based on poly(anthranilic acid-co-aniline) for detection of miRNA-155, a cancer biomarker

Traditional electrochemical biosensors often rely on expensive materials like gold nanoparticles within their electrode structures. In contrast to existing methods, this research introduces a novel, groundbreaking, label-free aptasensor. This sensor comprises simple and inexpensive materials, making it accessible and budget-conscious. It boasts exceptional sensitivity, allowing for the identification of leukemia cancer biomarker (miRNA-155) in its early stages. The proposed aptasensor consisted of a copolymer of poly anthranilic acid and polyaniline on the graphite sheet, in which the receptor of miRNA-155 was self-assembled on the copolymer. The substrate of receptors has benefits, including high electrical conductivity, excellent stability, good biocompatibility, and simple synthesis. The important variables affecting the adequacy of the designed aptasensor were examined in the presence of [Fe(CN)₆]^3-/4- as a redox probe. The proposed aptasensor was successfully used in human blood plasma. Due to the ease of preparation, cost, and time effectiveness, the proposed aptasensor is promising for mass production. Finally, at optimum conditions, the sensor exhibited a linear response within a concentration range of 0.1 nM to 1 aM with a detection limit of 1 aM.