Chiral MoS₂ Quantum Dots: Dual‐Mode Detection Approaches for Avian Influenza Viruses

Abstract

Molybdenum disulfide (MoS 2 ), a type of transition metal dichalcogenide material, has emerged as an important class among 2D systems. When 2D MoS 2 materials are reduced to 0D quantum dots (QDs), they introduce new optical properties that point to several potential technological advantages in electronic, magnetic, optical, and catalytic properties. In this study, a simple way to produce chiral MoS 2 QDs from MoS 2 nanopowder is presented using l (+)‐ascorbic acid as a reducing agent. The calculated quantum yield of QDs is 11.06%. Experimental results reveal that the size of QDs is uniformly monodispersed (2–3 nm) and have a blue emissive fluorescence peak and circular dichroism (CD) peak located at 420 and 330 nm, respectively. Furthermore, a dual‐mode detection system based on fluorescence and chirality is performed using as‐synthesized MoS 2 QDs, where QDs are conjugated with anti‐hemagglutinin antibodies of avian influenza virus and made into an immunobridge in the presence of target virus and anti‐neuraminidase antibodies conjugated magnetic nanoparticles (MNPs). The photoluminescence and CD spectra of unconjugated QDs after separated magnetochirofluorescent (MNPs‐QDs) nanohybrids by external magnets enables influenza virus A (H5N1) detection with the limit of detection value of 7.35 and 80.92 pg mL −1 , respectively.

Recent Progress on Two-Dimensional Materials

“…So far, many types of 2D materials have been fabricated into chiral ones, including the 2D perovskites 302,[663][664][665][666][667][668][669][670] , graphene [671][672][673] , TMDs [674][675][676][677] , 2D organic nanoassemblies 678 and many more. A key scientific issue is how the chirality is originated and how to endow the 2D materials with chirality.…”

Nanodots Derived from Layered Materials: Synthesis and Applications

“…[212] In recent years, a series of works have been done toward QD-based sensing of biomolecules, due to the novel PL, electrochemiluminescence (ECL) and electro-optical properties of QDs derived from layered materials. [59,63,157,[213][214][215][216][217] TMD QDs have been widely used to construct sensing platforms for biomolecules. Yan et al reported that Fe 3+ can quench the PL of WS 2 QDs through photoinduced electron transfer (Figure 12b).…”

“…MoS 2 QDs to detect avian influenza virus based on both PL and circular dichroism spectra. [214] With excellent PL, ECL properties and electro-optical activity, h-BN QDs are proved as another type of efficient biosensing probes. [59,215] For example, Gu et al utilized the PL intensity change of h-BN QDs to determine the activity of acetylcholinesterase (AChE).…”

Recent Advances in AIV Biosensors Composed of Nanobio Hybrid Material

“…Recently, Ahmed et al synthesized the molybdenum disulfide-QD (MoS 2 -QD) with magnetic nanoparticle for an FL-based AIV H5N1 detection system [79]. The MoS 2 is the transition metal dichalcogenide (TMD) material that is also called the topological insulator (TI) (Figure 5).…”

“…Fluorescence detection of avian influenza virus A (H5N1): ( B ) PL response before and after nanohybrids formation; ( C ) PL spectra of QDs with different concentrated target virus solution; ( D ) calibration curve of PL intensity versus virus concentration; and ( E ) selectivity results of fluorescence-based sensor. (Reproduced with permission from [79], published by WILEY-VCH Verlag GmbH & Co. KGaA, 2018).…”