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Cucurbituril complexes cross the cell membrane.
Pedro Montes-Navajas1, María González-Béjar, J C Scaiano
1Department of Chemistry, University of Ottawa, 10 Marie Curie, K1N 6N5, Ottawa, Canada.
Summary
Cucurbiturils (CBs) form stable complexes with dyes, enabling them to enter cells. These supramolecular host-guest systems show potential as nanocapsules for drug delivery applications.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Cell Biology
Background:
- Cucurbiturils (CBs) are macrocyclic hosts with growing importance in supramolecular chemistry.
- Developing efficient drug delivery systems requires stable carriers that can penetrate cell membranes.
Purpose of the Study:
- To investigate the complexation of cucurbiturils (CB[7] and CB[8]) with acridine orange (AO) and pyronine Y (PYY).
- To evaluate the potential of these cucurbituril-dye complexes as cell-penetrating nanocapsules for drug delivery.
Main Methods:
- Complexation studies were performed in phosphate buffer solution (PBS).
- Binding constants were determined using fluorescence spectroscopy via titration.
- Cellular uptake was visualized using fluorescence microscopy in 3T3 cells.
Main Results:
- CB[7] and CB[8] formed strong 1:1 and 2:1 host-guest complexes with AO and PYY, respectively.
- High binding constants (10^6 to 10^13 M^-1/M^-2) were observed, stabilizing the complexes.
- Fluorescence microscopy confirmed that the CB-dye complexes successfully crossed the cell membrane of 3T3 cells.
Conclusions:
- Cucurbituril-dye complexes exhibit high stability and cell permeability.
- These findings highlight the potential of cucurbiturils as effective nanocapsules for intracellular drug transport.
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