A robust post-insertion method for the preparation of targeted siRNA LNPs

  • Targeted delivery of nucleic acids is gaining momentum due to improved efficacy, selectivity, increased circulation time and enhanced tissue retention in target cells. Using nucleic acid-based therapies previously undruggable targets have proven now to be amenable for treatment. Currently, several methods for preparing targeted or labelled delivery vehicles for nucleic acids are based on liposomal formulations. Lipid nanoparticles (LNPs) are structurally different from liposomes and these methods should therefore be evaluated before being translated to siRNA LNPs preparation protocols. Here, we describe a robust and facile method for the preparation of targeted or fluorescently labelled siRNA LNPs. Using a copper free strain-promoted azide-alkyne cycloaddition (SPAAC) we demonstrate that post-insertion of ligand-lipid conjugates into preformed LNPs is superior to direct-surface modification because it preserves the physicochemical parameters of the LNPs. We found that the time point of solvent removal by dialysis is critical and affects the hydrodynamic diameter of the LNPs; post-insertion after dialysis shows the smallest increase in hydrodynamic diameter and polydispersity index (PDI). The post-insertion of ligand-lipid conjugates also proceeded with rapid kinetics and high efficacy over a wide temperature range. Using this optimised protocol, we generated siRNA LNPs containing both targeting and fluorescent tracking ligands allowing us to monitor siRNA LNP uptake kinetics in dependence of the targeting ligand. In aggregate, we describe a robust approach for the generation of targeted and labelled siRNA LNPs that allows their controlled and facile decoration with ligand combinations.
Author:Laura E. SwartORCiD, Cornelis Arnold KoekmanORCiD, Cor W. Seinen, Hasan Issa, Milad RasouliORCiD, Raymond Michel SchiffelersORCiD, Olaf Torben HeidenreichORCiDGND
Parent Title (English):International journal of pharmaceutics
Place of publication:New York, NY [u.a.]
Document Type:Article
Date of Publication (online):2022/04/11
Date of first Publication:2022/04/11
Publishing Institution:Universit├Ątsbibliothek Johann Christian Senckenberg
Release Date:2023/09/29
Tag:Click chemistry; Ligand post-insertion; Targeted delivery; copper free strain-promoted azide alkyne cycloaddition (SPAAC); siRNA lipid nanoparticles (LNPs)
Issue:art. 121741
Article Number:121741
Page Number:11
First Page:1
Last Page:11
This research was supported by KiKa programme grant 329 to OH.
Dewey Decimal Classification:6 Technik, Medizin, angewandte Wissenschaften / 61 Medizin und Gesundheit / 610 Medizin und Gesundheit
Licence (German):License LogoCreative Commons - CC BY - Namensnennung 4.0 International