Boron-doped-diamond coupling with gold nanoparticles to prepare a simple and highly rigid aptasensor for detection of bleomycin.

Background: Bleomycin (BLM), an essential antitumour medication in clinical applications, has detrimental effects on human health when it appears in an ecological environment, even at trace concentrations. It is desirable to detect trace amounts of BLM by a fast, simple, and efficient method, however, the traditional technologies (e.g., high-performance liquid chromatography, enzyme-linked immunosorbent assay, etc.) generally require expensive equipment and a complicated process, and/or have the disadvantages of long-time running times and poor repeatability. Electrochemical biosensors have been proposed as a fast, easy, sensitive, and cost-effective method for the detection of BLM, and finding a suitable work electrode plays a crucial role in realizing highly performance detection.

Results: In this work, based on a boron-doped diamond (BDD) electrode, coupling with gold (Au) nanoparticles, we design an electrochemical aptasensor for sensitive and specific detection of BLM, featuring a synergistic assembly of aptamers, Au nanoparticles, and BDD film. The BLM aptasensor presents a wide linear range in 1.0 × 10-1.0 × 10 mol L, and achieves a limit of detection as low as 8.5 × 10 mol L. The examinations of trace BLM serum also present a large region of 1.0 × 10-1.0 × 10 mol L. Besides, the interfering tests exibit that the relative responses (RR, %) are ranged from -4.1 % to 6.4 % in five similar structure interfer, and the daily RRs varies between between -3.3 % and 7.3 % in comparison to the 100 % for the first day, which domenstrating the high stability and repeatability and accuracy of the aptasensor.

Significance: The innovative aptasensor consisting of β-mercaptohexanol (MCH), Aptamers, Au-NPs, and BDD (MAA-BDD) for the electrochemical detection of trace BLM is of excellent sensitivity, specificity, rigidity, and repeatability, which is suitable for further practical applications on trace BLM detection in various environments.