RESUMEN
The effect of adding ethylammonium nitrate (EAN), which is an ionic liquid (IL), on the aggregate formation of α-synuclein (α-Syn) in aqueous solution has been investigated. FTIR and Raman spectroscopy were used to investigate changes in the secondary structure of α-Syn and in the states of water molecules and EAN. The results presented here show that the addition of EAN to α-Syn causes the formation of an intermolecular ß-sheet structure in the following manner: native disordered state â polyproline II (PPII)-helix â intermolecular ß-sheet (α-Syn amyloid-like aggregates: α-SynA). Although cations and anions of EAN play roles in masking the charged side chains and PPII-helix-forming ability involved in the formation of α-SynA, water molecules are not directly related to its formation. We conclude that EAN-induced α-Syn amyloid-like aggregates form at hydrophobic associations in the middle of the molecules after masking the charged side chains at the N- and C-terminals of α-Syn.
Asunto(s)
Agregado de Proteínas , Compuestos de Amonio Cuaternario/química , alfa-Sinucleína/química , Amiloide/síntesis química , Amiloide/química , Precipitación Química/efectos de los fármacos , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Agregado de Proteínas/efectos de los fármacos , Conformación Proteica en Lámina beta/efectos de los fármacos , Multimerización de Proteína/efectos de los fármacos , Estructura Secundaria de Proteína , Compuestos de Amonio Cuaternario/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Agua/químicaRESUMEN
SF/polyurethane composite non-woven sheet was fabricated to evaluate the cardiovascular tissue engineering materials in the wet state. The compatibility and microstructure analyses were carried out on the fabricated SF/polyurethane composite non-woven sheet by thermal analysis and solid-state NMR analysis in the wet state. To evaluate the modulus of elasticity, a tensile test was performed and supported with dynamic viscoelasticity and mechanical analysis. Results showed that SF/polyurethane composites form domains within the non-woven sheet and are in a finely dispersed state while maintaining their structures at a scale of several tens of nm. Moreover, an increase of the loss tangent with low elastic modulus proved that a micromolecular interaction occurs between silk fibroin (SF) and polyurethane molecules.