Exploring the molecular interaction between tryptophan and β-cyclodextrin modified ZnS quantum dots using...

Area of Science:

• Nanotechnology
• Biochemistry
• Analytical Chemistry

Background:

• Quantum dots (QDs) offer unique luminescent properties for sensing applications.
• Surface modification of QDs is crucial for enhancing selectivity and stability.
• Host-guest interactions are key for developing selective molecular probes.

Purpose of the Study:

• To investigate the luminescent properties of β-cyclodextrin surface-modified ZnS QDs (β-CD/ZnS QDs).
• To explore the host-guest interactions between β-CD/ZnS QDs and L-tryptophan (L-Trp).
• To develop a selective and sensitive probe for L-Trp detection.

Main Methods:

• Synthesis of water-soluble β-CD/ZnS QDs.
• Investigation of optical properties using fluorescence spectroscopy.
• Analysis of aggregation behavior using Dynamic Light Scattering (DLS).
• Characterization of interactions using UV-Visible, Raman, FTIR, and MALDI-MS.

Main Results:

• β-CD/ZnS QDs exhibited selective fluorescence enhancement for L-Trp via aggregation-induced emission.
• A binding constant of 1.75x10^-8M^-1 and a limit of detection (LOD) of 420 nM for L-Trp were determined.
• The probe demonstrated high recovery rates (91-97%) for L-Trp detection in soybean samples.

Conclusions:

• β-CD/ZnS QDs are effective fluorescent probes for selective L-Trp detection.
• The developed method offers a sensitive and reliable approach for analyzing L-Trp in complex matrices.
• This work highlights the potential of surface-modified QDs in biochemical sensing.