Impact of Sterilization on the Colloidal Stability of Ligand-Free Gold Nanoparticles for Biomedical Applications

Sterilization is a major prerequisite for the utilization of nanoparticle colloids in biomedicine, a process well examined for particles derived from chemical synthesis although highly underexplored for electrostatically stabilized ligand-free gold nanoparticles (AuNPs). Hence, in this work, we comp...

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Détails bibliographiques
Publié dans:Langmuir : the ACS journal of surfaces and colloids. - 1985. - 38(2022), 43 vom: 01. Nov., Seite 13030-13047
Auteur principal: Johny, Jacob (Auteur)
Autres auteurs: van Halteren, Charlotte E R, Zwiehoff, Sandra, Behrends, Carina, Bäumer, Christian, Timmermann, Beate, Rehbock, Christoph, Barcikowski, Stephan
Format: Article en ligne
Langue:English
Publié: 2022
Accès à la collection:Langmuir : the ACS journal of surfaces and colloids
Sujets:Journal Article Research Support, Non-U.S. Gov't Gold 7440-57-5 Reactive Oxygen Species Ligands
Description
Résumé:Sterilization is a major prerequisite for the utilization of nanoparticle colloids in biomedicine, a process well examined for particles derived from chemical synthesis although highly underexplored for electrostatically stabilized ligand-free gold nanoparticles (AuNPs). Hence, in this work, we comprehensively examined and compared the physicochemical characteristics of laser-generated ligand-free colloidal AuNPs exposed to steam sterilization and sterile filtration as a function of particle size and mass concentration and obtained physicochemical insight into particle growth processes. These particles exhibit long-term colloidal stability (up to 3 months) derived from electrostatic stabilization without using any ligands or surfactants. We show that particle growth attributed to cluster-based ripening occurs in smaller AuNPs (∼5 nm) following autoclaving, while larger particles (∼10 and ∼30 nm) remain stable. Sterile filtration, as an alternative effective sterilizing approach, has no substantial impact on the colloidal stability of AuNPs, regardless of particle size, although a mass loss of 5-10% is observed. Finally, we evaluated the impact of the sterilization procedures on potential particle functionality in proton therapy, using the formation of reactive oxygen species (ROS) as a readout. In particular, 5 nm AuNPs exhibit a significant loss in activity upon autoclaving, probably dedicated to specific surface area reduction and surface restructuring during particle growth. The filtered analog enhanced the ROS release by up to a factor of ∼2.0, at 30 ppm gold concentration. Our findings highlight the need for carefully adapting the sterilization procedure of ligand-free NPs to the desired biomedical application with special emphasis on particle size and concentration
Description:Date Completed 02.11.2022
Date Revised 15.12.2022
published: Print-Electronic
Citation Status MEDLINE
ISSN:1520-5827
DOI:10.1021/acs.langmuir.2c01557