Two-dimensional transition metal dichalcogenides assisted biofunctionalized optical fiber SPR biosensor for efficient and rapid detection of bovine serum albumin

Siddharth Kaushik,Umesh K Tiwari,Ravindra K Sinha,Akash Deep

doi:10.1038/s41598-019-43531-w

Abstract

The present study reports an alternative method of functionalizing the optical fiber Surface Plasmon Resonance (SPR) sensing probe with antibodies for label-free detection of bovine serum albumin (BSA) protein. In this novel approach, the gold coated fiber was first modified with Molybdenum disulfide (MoS2) nanosheets followed by its bio-functionalization with Anti-BSA antibodies. The developed technique not only allowed the amplification of the SPR signals by synergic effects of MoS2 and gold metallic thin film but also enabled a direct and chemical-free attachment of representative antibodies through hydrophobic interactions. The sensitivity of the MoS2 modified sensing probe with detection limit of 0.29 µg/mL was improved as compared to the fiber optic SPR biosensor without MoS2 overlayer (Detection limit for BSA was 0.45 μg/mL). The developed biosensor has good specificity, and environmental stability. Accordingly, the proposed design of the MoS2 based SPR optical biosensor can offer the development of a simplified optical device for the monitoring of various biomedical and environmental parameters.

Highlights

MoS2 nanosheets assisted biofunctionalized optical fiber surface plasmon resonance (SPR) sensor has been successfully demonstrated for specific detection of Bovine serum albumin (BSA) protein
The sensing probe functionalization with nanosheets and antibodies was characterized by different analytical techniques including Raman spectroscopy, transmission electron microscope (TEM), UV-Vis spectroscopy, FESEM, confocal imaging and XRD analysis
The sensing capabilities of the developed biosensor was compared with the fiber optic SPR biosensor without MoS2 overlayer

Summary

Introduction

Biosensors have been the focus of cutting-edge research in recent years as they possess desirable properties of high sensitivity, excellent specificity, good stability, easy operation, fast response and cost-effective analysis[1]. Considering these imperative features, a plethora of biosensing platforms including photoelectrochemical[2,3,4,5], impedance-based[6,7,8] and optical[9,10], were reported for sensitive and specific detection of chemical compounds and biomolecules. The normalized transmission power of the fiber optic SPR sensor is presented in eq (1)

Methods

Results

Conclusion