A Disposable and Highly Sensitive Aptamer Flexible Sensor for Detecting Human Serum Albumin

Abstract

We have constructed a gold nanoparticle-modified flexible aptamer sensor by optimizing electrochemical deposition and chemical immunoassay techniques. The aptamer is used to specifically capture human serum albumin (HSA), Differential pulse voltammetry (DPV) was used for electrochemical detection of HSA, and it was found that the DPV peak current value linearly correlates with the logarithm of HSA concentration between 0.1 pg/mL and 100 pg/mL, with a detection limit of 87 fg/mL. HAS is present in blood, cerebrospinal fluid, sweat, and other bodily fluids. Based on the high sensitivity of detecting HSA, this sensor has great potential for detecting HSA in sweat. In addition, we also demonstrated that the sensor has strong universality by detecting Retinol Binding Protein 4 (RBP4). Based on this, we have also constructed a "prussian blue-based aptasensor" that can undergo self-oxidation and reduction, providing a method for real-time detection of HSA.

Keywords: Cortisol aptamer sensor, Prussian blue aptamer sensor, Gold nanoparticles, Flexible sensor