Unraveling the genesis of large supramolecular structures obtained from single aryl amino acid-based molecules

FEDERICO MOVILLA; JUAN MANUEL REY; FLORENCIA DI SALVO; CRISTIÁN HUCK IRIART

Campinas

Conferencia; 30. RAU: annual users meeting LNLS/CNPEM; 2020

Molecular self-assembly refers to the spontaneous assembly of precursor molecules toform structures though noncovalent interactions.[1] In order to control the architecture ofthe resulting system, it is necessary to design building blocks assuring the presence ofthe functional groups which conduct to the development of stable intermolecularinteractions with the desired directionality. A large self-assembled supramolecularstructure can be obtained using small amino acid-based molecules as building blocks bychanging the physicochemical variables of the environment, namely ionic strength, thenature of the solvent, thermal history, an others [2]. These well-organizedsupramolecular assemblies are employed for several technological applications and theyare related to several degenerative disorders, including Alzheimer?s disease, Parkinson?sdiseases, and type II diabetes [3]. In this work, a lamellar-like self-assembly model inorganic media has been proposed based on single aryl amino acid, L-Phe or L-Tyr,derivatized with the aldehyde piperonal. The main core of the assembly was constructedby ionic intermolecular interactions assisted by H-bonds and, also, with the contributionof contacts involving the aromatic systems. This model was built using X-ray diffraction,density functional theory, small angle X-ray scattering and nuclear magnetic resonanceresults. The physicochemical entails described at molecular and nanometric levelestablish the seeds for the formation of crystalline and non-crystalline mesostructureswhich are triggered by the synthesis conditions.