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Yellow-emissive carbon dots as a fluorescent probe for chromium(VI)
Félicité Pacifique Mutuyimana1,2, Juanjuan Liu1,2, Stanislas Nsanzamahoro1,2
1State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou, 730000, China.
Abstract:
The authors describe a one-step method for the preparation of yellow fluorescent carbon dots (CDs) starting from 4-aminoacetanilide hydrochloride and 4-acetamidobenzaldehyde. The CDs have excitation/emission peaks at 470/550 nm, good water solubility, salt-tolerance and photostability. Their fluorescence is quenched by hexavalent chromium [Cr(VI)] via static quenching. Fluorescence intensity drops linearly in the 1 to 400 μM Cr(VI) concentration range, and the limit of detection is 0.13 μM. This method is selective for Cr(VI) over potential metal ion interferences and was successfully applied to the detection of Cr(VI) in spiked water and biological tissue samples. Recoveries from spiked samples ranged from 97.7% to 103.8%. Graphical abstract Schematic presentation of (a) the preparation of the CD fluorescent probe and (b), the principle of Cr(VI) determination.
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The Dot Product
Dot Product
In engineering, the dot product of any two vectors is the product of the magnitudes of the vectors and the cosine of the angle between them. It is denoted by a dot symbol between the two vectors.
Consider a vehicle pulling an object along the ground using a rope. If the rope makes an angle with the horizontal axis, the work done can be calculated using the dot product of the force applied and the object's displacement.
The dot...

