Chemical Modifications Influence the Number of siRNA Molecules Adsorbed on Gold Nanoparticles and the Efficiency of Downregulation of a Target Protein

Abstract

Small interfering RNAs (siRNAs) are a powerful tool for specific suppression of protein synthesis in the cell, and this determines the attractiveness of siRNAs as a drug. Low resistance of siRNA to nucleases and inability to enter into target cells are the most crucial issues in developing siRNA-based therapy. To face this challenge, we designed multilayer nanoconstruct (MLNC) with AuNP core bearing chemically modified siRNAs. We applied chemical modifications 2′-OMe and 2′-F substitutions as well as their combinations with phosphoryl guanidine group in the internucleotide phosphate. The effect of modification on the efficiency of siRNA loading into nanocarriers was examined. The introduction of the internucleotide modifications into at least one of the strands raised the efficiency of siRNA adsorption on the surface of gold core. We also tested the stability of modified siRNA adsorbed on gold core in the presence of serum. Based on loading efficiency and stability, MLNCs with the most siRNA effective cargo were selected, and they showed an increase in biological activity compared to control MLNCs. Our study demonstrated the effect of chemical modifications of siRNA on its binding to the AuNP-based carrier, which directly affects the efficiency of target protein expression inhibition.

The improving strategies and applications of nanotechnology-based drugs in hepatocellular carcinoma treatment

“…The development of other RNA drugs is still being explored. The introduction of internucleotide bonded phosphate modified oligonucleotides can improve the stability of siRNA and improve the silencing effect of target genes without potential side effects of treatment ( Epanchintseva et al, 2022 ).…”

Fixation and Visualization of Full Protein Corona on Lipid Surface of Composite Nanoconstruction

“…The AuNPs were synthesized as described in [13]. The preparation and characterization of cores from AuNP and siRNA are described in detail in [11,12]. The procedure for MLNC assembly is described in [11].…”

“…MLNCs incubated with FBS with/without UV irradiation (Section 2.4) were cleared of unbound proteins by centrifugation in 75% glycerol or 58% sucrose containing 1 mM PB at 2000× g and 25 • C for 15 min as described in [12].…”

“…MLNCs are composite nanoparticles designed to deliver siRNA into cells. The assembly process of MLNCs and their physicochemical properties have been studied in detail previously [11,12]. To precondense siRNA, we use gold nanoparticles (AuNPs), which can reversibly adsorb siRNA to their surface.…”