2.2. Preparation of siRNA/peptide complexes
GAPDH-siRNA was dissolved in HBSS as 1 μM, and all peptides were dissolved in HBSS or distilled water for 1-2 mg/mL. The sequences of all peptides were summarized in Table 1. The fusion peptides designed in this study have a GCG linker between SPACE and oligo arginine peptides. Fusion peptides and siRNAs in HBSS buffer formed the self-assembled complexes under incubation at room temperature (25°C) for 30 minutes with appropriate nitrogen/phosphate (N/P) ratio (Fig. 1). The N/P ratio was derived using the molar ratio of amine groups in the cationic peptides to those of phosphate groups in the RNA.