Surface Engineering of MoS₂ Quantum Dots via Cyclodextrin-Based Host–Guest Chemistry as Versatile Platforms for Enhanced Cell Imaging Application

Abstract

Transition metal chalcogenide quantum dots (QDs), especially MoS2 QDs, are an emerging class of novel optical probes for versatile bioanalytical applications owing to their distinct physicochemical properties. However, the reasonable use of these QDs for biological imaging has been largely restricted due to the challenge of controllable surface functionalization. In this work, we report a new strategy to engineer the surface of MoS2 QDs by taking advantage of cyclodextrin (CD)-based host–guest chemistry. The prepared β-CD-modified QDs (β-CD-MoS2 QDs) exhibit enhanced fluorescence properties, excellent biocompatibility, and good stability, making them promising as novel optical probes for bioimaging. Cellular imaging experiments revealed that these β-CD-MoS2 QDs can enter living cells through multiple internalization pathways, which differs significantly from pristine QDs. Particularly, we observed that the intracellular accumulation of MoS2 QDs in lipid droplets was enhanced owing to the specific binding of β-CD to cholesterol, which was then harnessed for monitoring the lipid metabolism in living cells via fluorescence imaging. Furthermore, we also demonstrated the potential use of β-CD-MoS2 QDs for targeted cell imaging and microplate-based cell recognition, which can be easily achieved via bioconjugation with functional motifs (e.g., folate acid) through host–guest chemistry. Altogether, these results illustrate the great potential of engineering the surface of MoS2 QDs and other analogous materials via CD-based host–guest chemistry for advancing their cell imaging applications.

Chirality‐Dependent Angiogenic Activity of MoS2 Quantum Dots toward Regulatable Tissue Regeneration

“…[4,5,45] To further elucidate the above chirality-dependent angiogenic activity of chiral MoS 2 QDs, their internalization efficiency by HUVECs was first investigated by confocal imaging by taking advantage of their intrinsic fluorescence. [56] As shown in Figure 5a,b, stronger green fluorescence from MoS 2 QDs was observed in d-MoS 2 QDs treated group than that of l-MoS 2 QDs. Quantitative analysis revealed that the average fluorescence intensity per cell after being treated with d-MoS 2 QDs was four times higher than that in l-MoS 2 QDs group.…”

Recent Advances in Two-Dimensional Nanomaterials for Healthcare Monitoring

“…Liang et al successfully engineered the surface of MoS 2 quantum dots (QDs) using cyclodextrin-based chemistry, resulting in β-CD-modified MoS 2 QDs. These modified QDs exhibited enhanced fluorescence, excellent biocompatibility, and stability, making them promising for diverse bioimaging applications . MoS 2 @PBMOF demonstrated good biocompatibility, promoting the healing of damaged tissues by facilitating the production of hemoglobin.…”

Enhanced Photoluminescence Quantum Yield of Colloidal MoS2 Quantum Dots by Optimization of Oleic Acid and Oleylamine for Light-Emitting Diode Applications

“…The enhanced optical properties of MoS 2 QDs make them highly suitable for application in optoelectronic devices such as photodetectors, , optical sensors, − electrochromic devices, and light-emitting diodes (LEDs) . The toxicity of QDs such as CdSe, PbS, and CdS curtails their usage in biomedical applications, while the low toxicity MoS 2 QDs is a good substitute. − Apart from enhanced optical properties, the increase in surface-to-volume ratio enables these QDs to find application in catalysis , and energy storage devices such as supercapacitors. − There are other materials in transition metal dichalcogenide family such as WS 2 and MoSe 2 with a bandgap larger than MoS 2 . , A detailed study of optical properties of MoS 2 QDs will be beneficial for optimization of PLQY of these similar structured materials also. − …”