Development of a novel biosensor for Creatine Kinase (CK-MB) using Surface Plasmon Resonance (SPR)

Abstract

In this paper, we report a new biosensor for detection of the cardiac biomarker Creatine Kinase (CK-MB) using Surface Plasmon Surface (SPR) technique, with the purpose of the diagnosis of Acute Myocardial Infarction (AMI). For this, we employed gold nanoparticles (AuNP) stabilized with Cysteamine (Cys), and functionalized with Creatine Phosphate (Pcrea), which promote an increase in the sensitivity and accuracy for creatine kinase (CK-MB) detection in saliva and urine samples. The characteristics of the electronic transfer of the sensor could be observed by Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry (CV), that showed significant redox peaks on electrode surface evidencing the high electron exchange process and low resistance charge transfer between the electrolyte solution and the modified surface. The morphological characteristics were confirmed by Atomic Force Microscopy (AFM), micro-Raman and Contact Angle (CA), as well as the adsorption and interaction processes between the materials, which could be observed by Surface Plasmon Resonance (SPR). The SPR analytical curve, ranged from 5.0 ng mL−1 to 100.0 ng mL−1, provided some important parameters, such as limit of detection (LOD) of 0.209 ng mL−1, limit of quantification (LOQ) of 0.696 ng mL−1, and sensitivity of 8.67 × 10–3 ± 0.17 × 10–3 (°) mL ng−1. The specific interaction between functionalized substrate and CK-MB demonstrates a high affinity of 15.14 ng mL−1 based on the Michaelis-Menten fitting.