![Quantitative SERS Detection of Uric Acid via Formation of Precise Plasmonic Nanojunctions within Aggregates of Gold Nanoparticles and Cucurbit[n]uril](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F61682.jpg&w=3840&q=50)
Binding affinities of cucurbit[n]urils with cations
Shuai Zhang1, Laura Grimm2, Zsombor Miskolczy3
1Department of Life Sciences and Chemistry, Jacobs University, Campus Ring 1, 28759, Bremen, Germany. w.nau@jacobs-university.de.
Chemical Communications (Cambridge, England)
|November 8, 2019
Summary
Cucurbit[n]urils (CBn) exhibit strong binding affinities for 19 inorganic cations in water. These high affinities have significant implications and can cause interferences in various applications.
Area of Science:
- Supramolecular Chemistry
- Coordination Chemistry
Background:
- Cucurbit[n]urils (CBn) are macrocyclic hosts known for their unique cage-like structures.
- Their ability to bind various guests has led to applications in sensing, separation, and drug delivery.
- Understanding cation binding is crucial for optimizing CBn-based systems.
Purpose of the Study:
- To quantify the binding constants of 19 inorganic cations with cucurbit[n]uril homologues (CBn, n = 5, 6, 7, 8) in aqueous solutions.
- To explore the implications and potential interferences arising from these strong host-guest interactions.
Main Methods:
- Spectrophotometric titration was employed to determine binding constants.
- Systematic variation of cation type and CBn homologue size was performed.
Main Results:
- High binding constants, ranging from millimolar to micromolar, were determined for 19 inorganic cations with CBn.
- The binding affinities were found to be dependent on both the cation and the size of the cucurbit[n]uril homologue.
- Significant interferences were observed due to the strong binding events.
Conclusions:
- Cucurbit[n]urils demonstrate potent binding capabilities towards a wide range of inorganic cations in water.
- The high affinities necessitate careful consideration of potential interferences in practical applications.
- These findings provide valuable insights for designing selective host-guest systems.
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