Encapsulation and Functionalization of Nanoparticles in Crosslinked Resorcinarene Shells

Area of Science:

• Supramolecular Chemistry
• Nanomaterials Science
• Organic Synthesis

Background:

• Colloidal gold nanoparticles are crucial in various applications.
• Stabilizing nanoparticle dispersions, especially in organic solvents, remains a challenge.
• Developing robust protective shells for nanoparticles is essential for their practical use.

Purpose of the Study:

• To synthesize resorcinarene-derived tetrathiols for gold nanoparticle extraction and stabilization.
• To investigate the formation of crosslinked shells around gold nanoparticles using olefin metathesis.
• To evaluate the stability and robustness of these crosslinked shells under various conditions.

Main Methods:

• Synthesis of resorcinarene-derived tetrathiols (cavitands 3 and 4) with terminal alkene sidechains.
• Extraction of colloidal gold nanoparticles from aqueous solutions into organic solvents.
• Crosslinking of nanoparticle shells using Grubbs olefin metathesis catalyst.
• Assessment of shell resistance to alkanethiol-induced desorption, oxidative conditions, and repeated precipitation/redispersion.

Main Results:

• Tetrathiols efficiently extracted gold nanoparticles and stabilized their organic dispersion.
• Grubbs catalyst treatment formed crosslinked resorcinarene shells resistant to high temperatures.
• Crosslinked shells derived from tetrabenzylthiol cavitand 4 demonstrated exceptional robustness.
• Nanoparticles in crosslinked shells withstood oxidative conditions and allowed further synthetic modification.

Conclusions:

• Resorcinarene-derived tetrathiols provide an effective method for gold nanoparticle stabilization.
• Crosslinked shells offer superior protection against desorption and harsh conditions.
• The developed system enables robust nanoparticle handling and opens avenues for functionalization.