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05:58
Detecting and Characterizing Protein Self-Assembly In Vivo by Flow Cytometry
Published on: July 17, 2019
Assessment of cooperativity in self-assembly
1Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, Via della Ricerca Scientifica, 00133 Roma, Italy.
Journal of the American Chemical Society
|December 18, 2003
Summary
A new method reveals that common self-assembly processes, like helicates and porphyrin ladders, lack positive cooperativity. This challenges previous findings and suggests cooperativity in artificial systems is rarer than believed.
Area of Science:
- Supramolecular Chemistry
- Chemical Thermodynamics
- Materials Science
Background:
- Self-assembly is crucial for creating complex molecular structures.
- Assessing cooperativity in self-assembly is challenging due to intertwined interactions.
- Previous methods like Scatchard and Hill plots have limitations for self-assembly.
Purpose of the Study:
- To develop and apply a novel method for assessing cooperativity in self-assembly.
- To re-evaluate cooperativity in established self-assembly systems (helicates, porphyrin ladders).
- To critically assess the suitability of existing cooperativity assessment methods for self-assembly.
Main Methods:
- Distinguishing between intermolecular and intramolecular processes.
- Comparing self-assembly reactions with corresponding reference reactions.
- Applying the new method to published data on helicate and porphyrin ladder self-assembly.
Main Results:
- The proposed method indicates an absence of positive cooperativity in both helicate and porphyrin ladder self-assembly.
- This contradicts previous conclusions suggesting positive cooperativity.
- Existing methods (Scatchard, Hill plots) are deemed inappropriate for self-assembly.
Conclusions:
- Positive cooperativity in artificial self-assembly may be less common than previously assumed.
- The new method provides a more accurate assessment of cooperativity in self-assembly.
- Re-evaluation of cooperativity is needed for systems involving both inter- and intramolecular interactions.
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