Sulfur quantum dot-based “ON–OFF–ON” fluorescence platform for detection and bioimaging of Cr(vi) and ascorbic acid in complex environmental matrices and biological tissues

Abstract

A SQDs-based “ON–OFF–ON” platform is constructed for detection of Cr(vi) and AA. SQDs are feasible for bioimaging of zebrafish embryos/larvae and HeLa cells.

Sensitive and selective determination of tetracycline in milk based on sulfur quantum dot probes

“… 35,36 The peaks observed at 3411 cm −1 and 1640 cm −1 are belonged to –OH and C O, respectively. 37 No other new IR peaks are observed from the synthesized SQDs, which indicates the physical interaction between the SQDs and PEG-400 instead of chemical interaction. The XPS and FT-IR characterization results above show that the surface of the synthesized SQDs is rich in hydrophilic groups, so the obtained SQDs have high water solubility and can be used as fluorescent probes in aqueous media.…”

“…33,34 The peaks centered at 1113 cm À1 and 950 cm À1 could be attributed to the stretching vibration of C-O-H or C-O-C. 33 The peak at 2873 cm À1 in PEG-400 is split into two relatively sharper peaks at 2912 cm À1 and 2876 cm À1 , both of them are attributed to the stretching vibration of C-H. 35,36 The peaks observed at 3411 cm À1 and 1640 cm À1 are belonged to -OH and C]O, respectively. 37 No other new IR peaks are observed from the synthesized SQDs, which indicates the physical interaction between the SQDs and PEG-400 instead of chemical interaction. The XPS and FT-IR characterization results above show that the surface of the synthesized SQDs is rich in hydrophilic groups, so the obtained SQDs have high water solubility and can be used as uorescent probes in aqueous media.…”

Synthesis of Fluorescent Sulfur Quantum Dots for Bioimaging and Biosensing

“…In addition to aqueous media, it was also found that SQDs can be utilized to detect Cr(VI) and AA in HeLa cells based on the fluorescence on–off–on phenomenon ( Figure 2E ). Wang’s group also used SQDs to detect Cr(VI) and AA in zebra fish embryos and larvae, and similar fluorescence on–off–on behavior was observed ( Xia et al, 2021 ).…”

“…Copyright 2021, American Chemical Society. (C) Reproduced, with permission, from Xia et al (2021) . Copyright 2021, Royal Society of Chemistry.…”

“…Green fluorescence was visible to both the cytoplasm and nucleus of Du145 cells after incubation with SQDs for 24 h. In addition to cell imaging, SQDs can also be used to label biological tissues. For example, Wang’s group reported the use of SQDs to label zebra fish and larvae ( Xia et al, 2021 ). After incubation with SQDs for 2 h, obvious blue fluorescence could be observed in the yolk of zebra fish embryos ( Figure 2C ), and the yolk and head of larvae, suggesting that SQDs hold potential for in vivo imaging application.…”