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Published on: June 28, 2024
A novel label-free fluorescent sensor for highly sensitive detection of bleomycin based on nitrogen-doped graphene
Xiaotong Liu1, Weidan Na1, Qing Liu1
1Department of Analytical Chemistry, College of Chemistry, Jilin University, Changchun, 130012, China.
Abstract:
In this work, we presented a novel label-free biosensor for rapid detection of bleomycinsulphate (BLM). The biosensor was based on the fluorescent "turn off-on" of nitrogen-doped graphene quantum dots (N-GQDs), which was prepared in a green way from citric acid and ammonia. The richness of carboxyl groups on the N-GQDs enabled strong adsorption of ssDNA to the surface of N-GQDs through π-π stacking interactions, resulting in the effective fluorescence quenching of N-GQDs system. The ssDNA underwent an irreversible cleavage event via the oxidative effect of BLM with Fe(II) as a cofactor, thus a turn-on fluorescence signal was observed. Thereby, the concentration of BLM can be quantitatively determined in a broad range from 0.34 nmol/L to 1300 nmol/L with a detection limit of 0.34 nmol/L. The presented method was applied to the determination of BLM in human serum samples with satisfactory results.
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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...

