Related Experiment Video
Updated: Feb 14, 2026

Compact Quantum Dots for Single-molecule Imaging
Published on: October 9, 2012
A fluorescent sensor based on thioglycolic acid capped cadmium sulfide quantum dots for the determination of dopamine
Sirinan Kulchat1, Wissuta Boonta1, Apinya Todee1
1Materials Chemistry Research Center, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002,Thailand.
Abstract:
A fluorescent sensor based on thioglycolic acid-capped cadmium sulfide quantum dots (TGA-CdS QDs) has been designed for the sensitive and selective detection of dopamine (DA). In the presence of dopamine (DA), the addition of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) activates the reaction between the carboxylic group of the TGA and the amino group of dopamine to form an amide bond, quenching the fluorescence of the QDs. The fluorescence intensity of TGA-CdS QDs can be used to sense the presence of dopamine with a limit of detection of 0.68μM and a working linear range of 1.0-17.5μM. This sensor system shows great potential application for dopamine detection in dopamine drug samples and for future easy-to-make analytical devices.
Related Concept Videos
Quantum Numbers
The Quantum-Mechanical Model of an Atom
Lewis Acids and Bases
A coordinate covalent bond (or dative bond) occurs when one of the atoms in the bond provides both bonding electrons. For example, a coordinate covalent bond occurs when a water molecule combines with a hydrogen ion to form a hydronium ion. A coordinate covalent bond also results when...
Ions as Acids and Bases
Salts are ionic compounds composed of cations and anions, either of which may be capable of undergoing an acid or base ionization reaction with water. Aqueous salt solutions, therefore, may be acidic, basic, or neutral, depending on the relative acid-base strengths of the salt’s constituent ions. For example, dissolving the ammonium chloride in water results in its dissociation, as described by the equation:
Bronsted-Lowry Acids and Bases
Acid-Base Titration Curves
For a titration carried out for 25.00 mL of...

