Isoreticular chemistry and applications of supramolecularly assembled copper−adenine porous materials

The useful concepts of reticular chemistry, rigid and predictable metal nodes together with strong and manageable covalent interactions between metal centers and organic linkers, have made the so-called metal–organic frameworks (MOFs) a flourishing area of enormous applicability. In this work, the e...

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Detalles Bibliográficos
Autores: Mena Gutiérrez, Sandra, Pascual Colino, Jon, Beobide Pacheco, Garikoitz, Castillo García, Oscar, Castellanos Rubio, Ainara, Luque Arrebola, Antonio, Maiza Razkin, Ekain, Mentxaka Salgado, Jon, Pérez Yáñez, Sonia
Tipo de recurso: artículo
Fecha de publicación:2023
País:España
Institución:Universidad del País Vasco
Repositorio:Addi. Archivo Digital para la Docencia y la Investigación
OAI Identifier:oai:addi.ehu.eus:10810/64546
Acceso en línea:http://hdl.handle.net/10810/64546
Access Level:acceso abierto
Palabra clave:metal-organic frameworks
crystal-structures
separation
isoreticular
opper-adenine
Descripción
Sumario:The useful concepts of reticular chemistry, rigid and predictable metal nodes together with strong and manageable covalent interactions between metal centers and organic linkers, have made the so-called metal–organic frameworks (MOFs) a flourishing area of enormous applicability. In this work, the extension of similar strategies to supramolecularly assembled metal–organic materials has allowed us to obtain a family of isoreticular compounds of the general formula [Cu7(μ-adeninato-κN3:κN9)6(μ3-OH)6(μ-OH2)6](OOC-R-COO)·nH2O (R: ethylene-, acetylene-, naphthalene-, or biphenyl-group) in which the rigid copper–adeninato entities and the organic dicarboxylate anions are held together not by covalent interactions but by a robust and flexible network of synergic hydrogen bonds and π–π stacking interactions based on well-known supramolecular synthons (SMOFs). All compounds are isoreticular, highly insoluble, and water-stable and show a porous crystalline structure with a pcu topology containing a two-dimensional (2D) network of channels, whose dimensions and degree of porosity of the supramolecular network are tailored by the length of the dicarboxylate anion. The partial loss of the crystallization water molecules upon removal from the mother liquor produces a shrinkage of the unit cell and porosity, which leads to a color change of the compounds (from blue to olive green) if complete dehydration is achieved by means of gentle heating or vacuuming. However, the supramolecular network of noncovalent interactions is robust and flexible enough to reverse to the expanded unit cell and color after exposure to a humid atmosphere. This humidity-driven breathing behavior has been used to design a sensor in which the electrical resistance varies reversibly with the degree of humidity, very similar to the water vapor adsorption isotherm of the SMOF. The in-solution adsorption properties were explored for the uptake and release of the widely employed 5-fluorouracil, 4-aminosalycilic acid, 5-aminosalycilic acid, and allopurinol drugs. In addition, cytotoxicity activity assays were completed for the pristine and 5-fluorouracil-loaded samples.