Dokumentenart: | Artikel | ||||
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Titel eines Journals oder einer Zeitschrift: | European Journal of Pharmaceutical Sciences | ||||
Verlag: | Elsevier | ||||
Ort der Veröffentlichung: | AMSTERDAM | ||||
Band: | 155 | ||||
Nummer des Zeitschriftenheftes oder des Kapitels: | 105520 | ||||
Datum: | August 2020 | ||||
Institutionen: | Chemie und Pharmazie > Institut für Pharmazie Chemie und Pharmazie > Institut für Pharmazie > Lehrstuhl Pharmazeutische Technologie (Prof. Göpferich) | ||||
Identifikationsnummer: |
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Stichwörter / Keywords: | HUMAN SERUM-ALBUMIN; SILICA NANOPARTICLES; STRATEGIES; ADSORPTION; SIZE; Nanotechnology; Drug targeting; Ligand of high molecular weight; Binding affinity | ||||
Dewey-Dezimal-Klassifikation: | 500 Naturwissenschaften und Mathematik > 540 Chemie | ||||
Status: | Veröffentlicht | ||||
Begutachtet: | Ja, diese Version wurde begutachtet | ||||
An der Universität Regensburg entstanden: | Ja | ||||
Dokumenten-ID: | 43673 |
Zusammenfassung
Functionalization of nanoparticles with ligands is a powerful tool to achieve efficient targeting of receptors expressed on specific cell types. For optimal ligand-receptor interactions, the ligands should be attached on the nanoparticle surface in a predictable manner with specific orientations and density that preserve their bioactivity. While there are many publications on nanoparticles ...
Zusammenfassung
Functionalization of nanoparticles with ligands is a powerful tool to achieve efficient targeting of receptors expressed on specific cell types. For optimal ligand-receptor interactions, the ligands should be attached on the nanoparticle surface in a predictable manner with specific orientations and density that preserve their bioactivity. While there are many publications on nanoparticles functionalized with small ligands that meet these requirements, achieving these conditions is particularly challenging for protein-based ligands of higher molecular weight. Proteins have complex and often fragile structures with numerous reactive residues, and they generally do not withstand harsh reaction conditions well. They are also prone to non-specific adsorption. Thus, conjugation strategies have to be considered carefully and optimized for each individual protein-based ligand as well as for the particle platform. In this study, we present a comprehensive approach for site-selective conjugation between aminated silica nanoparticles (SiNPs) and the single accessible thiol in human serum albumin (HSA) (66.5 kDa). We varied several reaction parameters including the density of amino groups on the particle surface, protein to amino group molar ratios, and linker length and evaluated their effect on colloidal stability, mode of protein attachment, protein density, and binding capacity of the tethered protein. We demonstrated that particle surface properties strongly impact covalent conjugation. For SiNPs with low amino group density (5,000 NH2/particle), only 25% of the available surface was covered with protein, and up to 90% of HSA was nonspecifically adsorbed. Adjusting the molar ratio of HSA and lengthening the linker did not substantially increase the amount of covalently-attached ligand. In contrast, SiNPs with high amino group density (20,000 NH2/particle) showed high protein loading accompanied by low levels of non-specific adsorption. Using a short linker and 1:1 HSA to NH2 molar ratio resulted in 70% surface coverage with HSA molecules. The mode of attachment and protein density strongly impacted the functionality of the immobilized HSA. High non-specific adsorption resulted in the loss of its binding capacity, whereas predominately covalently-conjugated HSA showed binding affinities higher than that of soluble HSA and had a Kd value in the range of about 6 to 12 nM. Our findings indicate that reaction parameters should be carefully assessed to obtain site-selective and specifically oriented conjugation that maintains the protein's binding capacity. The approach presented here may serve as general instruction for the immobilization of high molecular weight targeting proteins to the surfaces of nanoparticles.
Metadaten zuletzt geändert: 29 Sep 2021 07:41