1. "Fluorescence-wavelength" label-free POCT tandem with "fluorescence-photothermal" nanobody-immunosensor for detecting BSA and β-lactoglobulin.
- Author
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Li S, Nie L, Yang L, Fan D, Wang J, Hu Y, Zhang Y, and Wang S
- Subjects
- Serum Albumin, Bovine, Lactoglobulins, Spectrometry, Fluorescence, Immunoassay, Carbon, Fluorescent Dyes, Biosensing Techniques, Quantum Dots
- Abstract
Two carbon dots (CDs) (λ
Em = 525 nm, G-CDs and λEm = 640 nm, R-CDs) were synthesized from citric acid and urea. The bovine serum albumin (BSA) responsiveness of the R-CDs was used to develop a "fluorescence-wavelength" label-free point of care testing (POCT) for the detection of the milk quality marker BSA with the detection limit (LOD) of 4.89 μg/mL for fluorescence mode and 3.38 μg/mL for wavelength mode. In addition, R-CDs were found to have hydroxyl radical (·OH)-dependent fluorescence quenching properties, and a "fluorescence-photothermal" immunosensor based on nanobodies was constructed by introducing the fluorescence signal of R-CDs@BSA and the photothermal signal of oxTMB for the detection of β-lactoglobulin (β-LG) with the LOD of 0.034 ng/mL for fluorescence mode and 0.075 ng/mL for photothermal mode. The tandem detection of POCT and immunosensor enables the simultaneous and highly sensitive detection of BSA and β-LG after only simple dilution of less than 5 µL of sample., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)- Published
- 2024
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