Label-Free Ultrasensitive Memristive Aptasensor

Abstract

We\npresent the very first worldwide ever-reported electrochemical\nbiosensor based on a memristive effect and DNA aptamers. This novel\ndevice is developed to propose a completely new approach in cancer\ndiagnostics. In this study, an affinity-based technique is presented\nfor the detection of the prostate specific antigen (PSA) using DNA\naptamers. The hysteretic properties of memristive silicon nanowires\nfunctionalized with these DNA aptamers provide a label-free and ultrasensitive\nbiodetection technique. The ultrasensitive detection is hereby demonstrated\nfor PSA with a limit of detection down to 23 aM, best ever published\nvalue for electrochemical biosensors in PSA detection. The effect\nof polyelectrolytes on our memristive devices is also reported to\nfurther show how positive or negative charges affect the memristive\nhysteresis. With such an approach, combining memristive nanowires\nand aptamers, memristive aptamer-based biosensors can be proposed\nto detect a wide range of cancer markers with unprecedent ultrasensitivities\nto also address the issue of an early detection of cancer.