Lysozyme–aunps interactions: Determination of binding free energy

Investigation and optimization of lysozyme (Lys) adsorption onto gold nanoparticles, AuNPs, were carried out. The purpose of this study is to determine the magnitude of the AuNPs– lysozyme interaction in aqueous media by simple spectrophotometric means, and to obtain the free energy of binding of th...

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Detalles Bibliográficos
Autores: Gomes, Axel, Carnerero Panduro, José María, Jiménez Ruiz, Aila, Grueso Molina, Elia María, Giráldez Pérez, Rosa María, Prado Gotor, Rafael
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/128803
Acceso en línea:https://hdl.handle.net/11441/128803
https://doi.org/10.3390/nano11082139
Access Level:acceso abierto
Palabra clave:Binding free energy
Gold nanoparticles
Lysozyme
Nanoparticle size
Surface plasmon resonance
Descripción
Sumario:Investigation and optimization of lysozyme (Lys) adsorption onto gold nanoparticles, AuNPs, were carried out. The purpose of this study is to determine the magnitude of the AuNPs– lysozyme interaction in aqueous media by simple spectrophotometric means, and to obtain the free energy of binding of the system for the first time. In order to explore the possibilities of gold nanoparticles for sensing lysozyme in aqueous media, the stability of the samples and the influence of the gold and nanoparticle concentrations in the detection limit were studied. ζ potential measurements and the shift of the surface plasmon band showed a state of saturation with an average number of 55 Lys per gold nanoparticle. Lysozyme–AuNPs interactions induce aggregation of citrate-stabilized AuNPs at low concentrations by neutering the negative charges of citrate anions; from those aggregation data, the magnitude of the interactions has been measured by using Benesi–Hildebrand plots. However, at higher protein concentrations aggregation has been found to decrease. Although the nanocluster morphology remains unchanged in the presence of Lys, slight conformational changes of the protein occur. The influence of the size of the nanoclusters was also investigated for 5, 10, and 20 nm AuNPs, and 10 nm AuNPs was found the most appropriate.