Related Experiment Video
Updated: Feb 2, 2026

Author Spotlight: Advancing SERS Technology: Au@Carbon Dot Nanoprobes for Label-Free Analysis and Imaging
Published on: June 9, 2023
A conjugated carbon-dot-tyrosinase bioprobe for highly selective and sensitive detection of dopamine
Zhongdi Tang1, Kai Jiang, Shan Sun
1Key Laboratory of Graphene Technologies and Applications of Zhejiang Province, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo 315201, P. R. China. wangyuhui@nimte.ac.cn linhengwei@nimte.ac.cn.
Abstract:
In this work, a bioprobe for the detection of dopamine was designed and fabricated through covalently linking fluorescent carbon dots (CDs) and tyrosinase (TYR). The bioprobe (named CDs-TYR) can catalyze oxidation of dopamine and produce dopaquinone, and consequently the fluorescence of the CDs was quenched due to an efficient electron transfer mechanism from excited CDs to dopaquinone. The fluorescence intensity of CDs decreased in a dopamine-concentration-dependent manner, which built the foundation of dopamine quantification. The bioprobe provided a wide linear range from 0.1 to 6.0 μM for dopamine sensing. Additionally, excellent selectivity of the bioprobe to dopamine was achieved because of the specific catalytic character of the conjugated TYR. Furthermore, the bioprobe was successfully employed for the detection of dopamine in spiked human serum. To the best of our knowledge, this is the first example of the construction of a bioprobe through conjugating CDs and an enzyme. This work would open new opportunities to develop CD-based photoinduced electron transfer bioprobes for other analytes via linking typical enzymes onto CDs.
Related Concept Videos
The Carbon Cycle
Conjugated Proteins
Nucleoproteins are protein complexes that contain nucleic acids, categorized as deoxyribonucleoproteins (DNPs) or ribonucleoproteins (RNPs) respectively. The nucleosome is a typical example of a DNP where nuclear DNA is associated with histone proteins. The major antigen for the Covid-19 virus SARS-CoV is an RNP that is critical...
Conjugated Proteins
Carbon Skeletons
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...
The Dot Product

