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Updated: Jan 31, 2026
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Accurate Determination of the Equilibrium Surface Tension Values with Area Perturbation Tests
Published on: August 30, 2019
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Measuring Critical Micelle Concentration as a Function of Cavitand Additives Using Surface Tension and Dye
Massiel Trujillo1, Michael P Schramm2
1Department of Biological Sciences.
Ronald E. Mcnair Postbaccalaureate Achievement Program : [Journal]
|January 11, 2019
Summary
The addition of cavitands, vase-shaped receptors, increased the critical micelle concentration (CMC) of hexadecylphospholcholine (HePC) surfactant. This study explores cavitand interactions with amphiphiles for potential applications in biological systems.
Area of Science:
- Supramolecular Chemistry
- Physical Chemistry
- Materials Science
Background:
- Additives can alter amphiphile critical micelle concentration (CMC) through specific interactions or solvent modification.
- Cavitands are vase-shaped molecular receptors with potential applications in molecular recognition.
Purpose of the Study:
- To investigate the effect of cavitands on the CMC of hexadecylphospholcholine (HePC).
- To evaluate cavitand-amphiphile interactions for predicting behavior in complex lipid systems.
Main Methods:
- Surface tension measurements using Wilhelmy plate, micropipette, and filter paper methods.
- Dye micellization monitored by fluorescent spectrophotometry.
- Determination of CMC for HePC with and without cavitand additives.
Main Results:
- The CMC of HePC was determined to be 17.8 µM using standard methods.
- Addition of 50 µM cavitand increased the HePC CMC to 31.6 µM.
- Dye micellization method yielded inconclusive results with cavitand addition.
Conclusions:
- Cavitands significantly influence the CMC of HePC, indicating specific interactions.
- Understanding these effects is crucial for designing cavitands as membrane receptors.
- This research provides a foundation for studying cavitand behavior in biological lipid bilayers.
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