Skip to main content
. Author manuscript; available in PMC: 2024 Oct 29.
Published in final edited form as: Mol Pharm. 2024 Feb 19;21(5):2163–2175. doi: 10.1021/acs.molpharmaceut.3c00747

Figure 4. PEI−RNA interactions.

Figure 4

(A) Depiction of siRNA complexation with various MW PEIs, highlighting the distinct structural interactions. (B) Multiple siRNAs cross-linked via PEI bridges, revealing the capability of PEIs to connect several RNA molecules. (C) Complexation thermodynamics for different PEIs, as quantified by micro-ITC analysis (n = 4). (D) Examination of the relationship between N/P ratio and unbound siRNA in complexation behavior as determined by fluorescence intercalation, demonstrating the efficiency of complexation across various ratios (n = 3). (E) Investigation of the energy landscape of DNA/PEI complexation at two distinct pH levels measured using single-molecule spectroscopy of molecular balances. (F) Binding/unbinding events of 1.3 kDa PEI to siRNA over time. (G) Influence of pH on the complexation free energy ΔG, derived from MD simulations at increasing N/P ratios and two distinct pH levels.