Electrospun SnO2 nanofibers-based electrochemical sensor using AB (1-40) for early detection of Alzheimer’s

An early diagnosis of Alzheimer’s disease (AD) is challenging and affects millions worldwide. AB(1-40), a potential biomarker found in cerebrospinal fluid, blood, and its derivatives, is utilized as an alternative for an early diagnosis of Alzheimer’s. This work presents an early detection of AD with the help of label-free electrochemical transduction mechanisms using AB(1-40) as a biomarker. To increase the diversity of decision-making parameters that inherently improve the disease’s diagnostic accuracy, the detection was carried out with the help of DPV and EIS analysis. The sensing platform utilized electrospun tin-oxide (SnO2) nanofibers modified carbon electrodes as a transducing element comprising covalently immobilized AB(1-40) antibodies on which the target AB(1-40) binds specifically. The sensing platform detected the target analyte concentrations prepared in real-time human blood plasma in the linear detection range of 1 fg/mL – 10 ng/mL and 1 fg/mL – 100 pg/mL obtained from DPV and EIS, respectively. It also accounted for an extremely low detection limit of 0.785 and 0.573 fg/mL and a very high sensitivity of 4.095 (μA/(ng/mL))/cm2 and 285.94 (kΩ/(ng/mL))/cm2 obtained from DPV and EIS, respectively. Further, the proposed sensing platform showed excellent selectivity, repeatability, reproducibility and high interference resistance.