Visualization of 2D and 3D Tissue Models via Size-Selected Aqueous AgInS/ZnS Quantum Dots

Area of Science:

• Biomedical Engineering
• Materials Science
• Nanotechnology

Background:

• Three-dimensional (3D) spheroid cell cultures offer more physiologically relevant models than 2D cultures for evaluating nanomaterials.
• Predicting the in vivo behavior of quantum dots (QDs) requires understanding their interactions with complex biological environments.

Purpose of the Study:

• To evaluate the biocompatibility and tissue imaging potential of ternary silver indium sulfide/zinc sulfide (AgInS/ZnS) fraction quantum dots (QDs).
• To compare the efficacy of 3D spheroid models versus 2D cell cultures for assessing QD effects on cell viability.

Main Methods:

• Separation of specific AgInS/ZnS QD fractions (emitting 635-535 nm) using antisolvent-induced precipitation.
• Assessment of QD toxicity and cellular uptake in both 2D and 3D fibroblast (L929) and mammary tumor (4T1) cell cultures.
• Correlation analysis of QD size, biological fluid interactions, cellular penetration, and selectivity.

Main Results:

• Ternary AgInS/ZnS fraction QDs demonstrated no observed toxicity across various concentrations in both 2D and 3D cell models.
• QD penetration into 2D and 3D cell structures was observed, with selectivity noted for cancerous versus healthy cell spheroids.
• A correlation was established between QD size in biological fluids, cellular penetration capabilities, and targeting selectivity.

Conclusions:

• Ternary AgInS/ZnS fraction QDs are non-toxic and suitable for biological applications.
• 3D spheroid models provide valuable insights into QD-tissue interactions, complementing 2D culture studies.
• These QDs exhibit potential as fluorescent contrast agents for advanced tissue imaging applications.