Surface plasmon resonance aptasensor based on niobium carbide MXene quantum dots for nucleocapsid of SARS-CoV-2 detection

Abstract

A novel label-free surface plasmon resonance (SPR) aptasensor has been constructed for the detection of N-gene of SARS-CoV-2 by using thiol-modified niobium carbide MXene quantum dots (Nb 2 C-SH QDs) as the bioplatform for anchoring N-genetargeted aptamer. In the presence of SARS-CoV-2 N-gene, the immobilized aptamer strands changed their conformation to specifically bind with N-gene. It thus increased the contact area or enlarged the distance between aptamer and the SPR chip, resulting in a change of the SPR signal irradiated by the laser (He-Ne) with the wavelength (λ) of 633 nm. Nb 2 C QDs were derived from Nb 2 C MXene nanosheets via a solvothermal method, followed by functionalization with octadecanethiol through a self-assembling method. Subsequently, the gold chip for SPR measurements was modified with Nb 2 C-SH QDs via covalent binding of the Au-S bond also by self-assembling interaction. Nb 2 C-SH QDs not only resulted in high bioaffinity toward aptamer but also enhanced the SPR response. Thus, the Nb 2 C-SH QD-based SPR aptasensor had low limit of detection (LOD) of 4.9 pg mL −1 toward N-gene within the concentration range 0.05 to 100 ng mL −1 . The sensor also showed excellent selectivity in the presence of various respiratory viruses and proteins in human serum and high stability. Moreover, the Nb 2 C-SH QD-based SPR aptasensor displayed a vast practical application for the qualitative analysis of N-gene from different samples, including seawater, seafood, and human serum. Thus, this work can provide a deep insight into the construction of the aptasensor for detecting SARS-CoV-2 in complex environments.

A review on corona virus disease 2019 (COVID-19): current progress, clinical features and bioanalytical diagnostic methods

“…Furthermore, the Nb 2 C-SH QD-based SPR aptasensor demonstrated a wide range of applications for qualitative N-gene analysis in a variety of samples, including seafood, seawater and human blood. As a result, our research can shed light on how the aptasensor for detecting SARS-CoV-2 in complicated settings is built [120].…”

“…The scheme of production of Nb 2 C-SH QDs and the fabrication of an Nb 2 C-SH QD-based SPR aptasensor for detecting the SARS-CoV-2 N-gene. Reproduced with permission from[120]…”

Recent advances of functional nucleic acid-based sensors for point-of-care detection of SARS-CoV-2

“…B Schematic of the Nb2C-SH QD-based SPR aptasensor for detecting the N gene of SARS-CoV-2. Reproduced with permission from [ 68 ], Copyright 2021 , Spring Nature …”

“…The incorporation of nanomaterials can broaden the detector and signal readout; for example, Chen et al [ 68 ] constructed a novel aptamer-based unlabeled surface plasmon resonance (SPR) approach to detect the SARS-CoV-2 N gene (Fig. 5B ).…”

An Electrochemical Impedance Spectroscopy-Based Aptasensor for the Determination of SARS-CoV-2-RBD Using a Carbon Nanofiber–Gold Nanocomposite Modified Screen-Printed Electrode

“…For this reason, there is a growing interest in the fabrication of a highly selective and sensitive device to diagnose the related virus that is called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). By now, several methods have been reported for the sensitive detection of the SARS-CoV-2 in the literature, such as gene-based [1,2], immune-based [3,4] aptamerbased [5,6], and molecularly imprinted polymer-based assays [7,8]. The gene-based method is the most widely used [6,9,10].…”