Tungsten disulfide (WS2)/fluorescein ratiometric fluorescent probe for detection of cefixime residues in milk

• Published in: Environmental research Vol. 205; p. 112512
• Main Authors: Haddad Irani-nezhad, Mahsa, Jalili, Roghayeh, Kohan, Elmira, Khataee, Alireza, Yoon, Yeojoon
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01.04.2022
• Subjects: Animals; Cefixime; Fluorescein; Fluorescence; Fluorescent Dyes - chemistry; Milk; Ratiometric sensor; Spectrometry, Fluorescence; Sulfides; Tungsten Compounds; WS2 QDs; Fluorescence; Ratiometric sensor; Cefixime; WS2 QDs; Fluorescein; WS QDs
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2021.112512

In this research work, it has been reported a ratiometric fluorescent sensor based on tungsten disulfide quantum dots (WS2 QDs) and fluorescein for the determination of Cefixime (CEF). When excited by radiation of 400 nm wavelength the probe illustrates dual emissions centered at 460 nm and 510 nm. CEF quenches the fluorescence (FL) intensity of fluorescein (510 nm), while it doesn't affect the FL emission of WS2 QDs at 460 nm. The change in the ratio of the two peaks (F460/F510) of the prepared sensor (WS2 QDs/fluorescein) is linearly proportional to the CEF concentration in the range of 200–2.500 ng/mL with a limit of detection (LOD) of 45 ng/mL. Hence, the proposed probe can be successfully used for CEF quantification in the milk samples. •WS2 QDs were synthesized by a simple and one-pot procedure.•Synthesized QDs exhibited dual emission when blended with fluorescein, which can be used as a ratiometry fluorescence sensor.•The ratiometric fluorescent sensor can detect cefixime in nanomolar levels.