Excitation-dependent multiple luminescence emission of nitrogen and sulfur co-doped carbon dots for cysteine sensing, bioimaging, and photoluminescent ink applications

Dual-Emissive Near-Infrared Carbon Dot-Based Ratiometric Fluorescence Sensor for Lysozyme

“…Sulfhydryl groups have a strong nucleophilic interaction with amino and imine, which can cause fluorescence quenching of dNIR-CDs. 44 Meanwhile, due to the large number of hydroxyl, carboxyl, and amino groups, hydrogen bond interactions could participate in the LYZ recognition. 45 Consequently, the mechanism of the nanosensor for LYZ detection was dynamic quenching, which was the result of the combined action of many factors (Scheme S1), including electrostatic interactions, the change of the LYZ microenvironment, and the interaction between functional groups.…”

“…LYZ contains sulfhydryl groups, while the surface of dNIR-CDs contains rich amino and imine groups. Sulfhydryl groups have a strong nucleophilic interaction with amino and imine, which can cause fluorescence quenching of dNIR-CDs . Meanwhile, due to the large number of hydroxyl, carboxyl, and amino groups, hydrogen bond interactions could participate in the LYZ recognition .…”

Microwave-assisted annulation for the construction of pyrido-fused heterocycles and their application as photoluminescent chemosensors

“…7a and b). 36 The probe 3a , its 3a /Fe 3+ and 3a /Ag + complexes showed different PL intensities. The quantum yield of probe 3a significantly decreased from 4.60% to 0.36% ( 3a /Fe 3+ ) and 1.61% ( 3a /Ag + ) complexes, where quinine sulfate was used as standard with a quantum yield of 54.6%.…”

Recent developments in carbon dot-based green analytical methods: new opportunities in fluorescence assays of pesticides, drugs and biomolecules

“…In view of this, fluorescent CDs have been fabricated for the development of fluorescent biosensors for the detection of trace-level biomolecules in different biofluids. Briefly, glucose, 161 cysteine, 162 vitamin B 12 , 163 hyaluronidase, 164 cytochrome c 165,166 and acetylcholinesterase 167 have been selectively quantified by using CDs as biosensors. The developed CD-based biosensor showed a good linear range from 1.0 to 12.0 mM with a LOD of 0.25 mM, successfully applied to quantify glucose in a blood sample.…”

“…A one-pot hydrothermal method was established for the fabrication of NSCDs with multi-emission properties. 162 The NSCDs acted as a nanosensor for the detection of cysteine, exhibiting a wider linear range from 0 to 10 μM, offering a LOD of 23 nM, which could be used as a promising probe for sensing cysteine in biofluids. A facile and sensitive fluorescence approach was developed for assaying vitamin B 12 by using CDs as a nanoprobe via the IFE mechanism.…”