Engineered Two-Dimensional Nanostructures as SERS Substrates for Biomolecule Sensing: A Review

Abstract

Two-dimensional nanostructures (2DNS) attract tremendous interest and have emerged as potential materials for a variety of applications, including biomolecule sensing, due to their high surface-to-volume ratio, tuneable optical and electronic properties. Advancements in the engineering of 2DNS and associated technologies have opened up new opportunities. Surface-enhanced Raman scattering (SERS) is a rapid, highly sensitive, non-destructive analytical technique with exceptional signal amplification potential. Several structurally and chemically engineered 2DNS with added advantages (e.g., π–π* interaction), over plasmonic SERS substrates, have been developed specifically towards biomolecule sensing in a complex matrix, such as biological fluids. This review focuses on the recent developments of 2DNS-SERS substrates for biomolecule sensor applications. The recent advancements in engineered 2DNS, particularly for SERS substrates, have been systematically surveyed. In SERS substrates, 2DNS are used as either a standalone signal enhancer or as support for the dispersion of plasmonic nanostructures. The current challenges and future opportunities in this synergetic combination have also been discussed. Given the prospects in the design and preparation of newer 2DNS, this review can give a critical view on the current status, challenges and opportunities to extrapolate their applications in biomolecule detection.

Large area CVD-grown vertically and horizontally oriented MoS2 nanostructures as SERS biosensors for single molecule detection

“…The calculation details regarding the number of biomolecules and EF are provided in section S10 and S11 of the ESI. † After substituting all the calculated parameters in eqn (8), the final values of EF for bilirubin using the ∼1613 cm −1 peak on H-MoS 2 /FTO, V-MoS 2 / Si, V-MoS 2 /SiO 2 -Si and H-MoS 2 /SiO 2 -Si substrates are 4.9 × 10 7 , 7.4 × 10 7 , 1.7 × 10 6 and 1.7 × 10 5 , respectively, while the final values of EF for vitamin B 12 using the ∼1500 cm −1 peak on H-MoS 2 /FTO, V-MoS 2 /Si, V-MoS 2 /SiO 2 -Si and H-MoS 2 /SiO 2 -Si substrates are 8.1 × 10 4 , 7.1 × 10 4 , 9.2 × 10 3 and 1.2 × 10 3 , respectively. A comparison of the SERS detection limit of both the biomolecules on different SERS substrates with previously reported works are given in Table 1.…”

“…The EM mechanism arises because of localized surface plasmon resonance, while the CM mechanism follows charge transfer (CT) between the SERS substrate and analyte molecules. [7][8][9][10] Semiconducting substrates being low cost, stable, and abundant and their easy integration with electronic devices have opened them up to being widely investigated as SERS substrates. 11,12 Among semiconductors, twodimensional (2D) layered transition metal dichalcogenide (TMD) nanomaterials are potential candidates for SERS owing to their unique features like quantum confinement, tunable bandgap, high carrier mobility, excellent biocompatibility, large surface area with accessible edges, high chemical stability and distinctive charge transfer capability.…”

Detection of type-Ⅱ diabetes using graphene-based biosensors

“…2D materials have emerged as promising biosensors for various amino acids due to their unique properties such as large surface-to-volume ratio, exceptional mechanical strength, and excellent biocompatibility [17]. These materials have been extensively studied in the literature for their role as biosensors for various amino acids, including valine [17][18][19]. The large surface area of 2D materials provides a high density of active sites for the adsorption of amino acids, which can be detected using various techniques such as electrochemical, optical, and mass-based sensing [17].…”

Recent Trends in SERS-Based Plasmonic Sensors for Disease Diagnostics, Biomolecules Detection, and Machine Learning Techniques

“…Advents in plasmonics have led to the emergence of SERS with impressive signal enhancements over traditional Raman spectroscopy [ 16 ]. SERS-based sensing is being widely used for the trace detection of different molecules, such as explosives [ 17 ], pesticides [ 18 , 19 ], food adulterants [ 20 , 21 ], drugs [ 22 ], biomolecules [ 23 , 24 , 25 , 26 , 27 ], medicine [ 28 , 29 , 30 ], and microorganisms [ 31 ].…”