Lateral Flow Aptasensor for Simultaneous Detection of Platelet-Derived Growth Factor-BB (PDGF-BB) and Thrombin.

Guodong Liu,Anant Gurung,Wanwei Qiu

doi:10.3390/molecules24040756

Abstract

Here we report a lateral flow aptasensor (LFA) for the simultaneous detection of platelet-derived growth factor-BB (PDGF-BB) and thrombin. Two pairs of aptamers, which are specific against PDGF-BB and thrombin, respectively, were used to prepare the LFA. Thiolated aptamers were immobilized on a gold nanoparticle (AuNP) surface and biotinylated aptamers were immobilized on the test zones of an LFA nitrocellulose membrane. The assay involved the capture of PDGF-BB and thrombin simultaneously in sandwich-type formats between the capture aptamers on the test zones of LFA and AuNP-labeled detection aptamers. AuNPs were thus captured on the test zones of the LFA and gave red bands to enable the visual detection of target proteins. Quantitative results were obtained by reading the test band intensities with a portable strip reader. By combining the highly specific molecular recognition properties of aptamers with the unique properties of lateral flow assay (low-cost, short assay time and a user-friendly format), the optimized aptasensor was capable of simultaneously detecting 1.0 nM of PDGF-BB and 1.5 nM of thrombin in association with a 10-min assay time. The biosensor was also successfully applied to detect PDGF-BB and thrombin in spiked human serum samples. The LFA shows great promise for the development of aptamer-based lateral flow strip biosensors for point-of-care or for the in-field detection of disease-related protein biomarkers.

Highlights

The detection and the quantification of proteins play pivotal roles in basic discovery research and clinical applications [1]
Once the solution passed through the test zones, excess gold NP-detection aptamer conjugates were captured on the control zone via the hybridization events between the control DNA probes and the capture aptamers, forming a third red band
The peak areas were proportional to the amounts of captured AuNPs on the test zones, which were proportional to the concentrations of plateletderived growth factor-BB (PDGF-BB) and thrombin in the sample solution

Summary

Introduction

The detection and the quantification of proteins play pivotal roles in basic discovery research and clinical applications [1]. Thrombin is an extracellular serine protease that plays a crucial role in the blood coagulation cascade, thrombosis, and hemostasis [2,3]. The concentration of thrombin is connected to various coagulation abnormalities [4]. Platelet-derived growth factor (PDGF) is an important growth factor protein in human platelets that regulates cell growth and division toward fibroblasts, smooth muscle cells, and glial cells [5]. The precise and sensitive evaluation of these proteins in biological samples will be substantial for disease diagnosis and biomedical applications. The gold standard method for the detection of PDGF and thrombin is enzyme-linked immunosorbent assay (ELISA), which involves antibodies and an enzyme label [7,8]. The utilization of antibodies may encounter some drawbacks with their production, stability, and modification

Methods

Results

Conclusion