Si5-N14 is a key component of siloxane-linked lipid nanoparticles (SiLNP) with properties that enhance vascular repair and exhibit antitumor activity. In transgenic GFP mouse models, Si5-N14 mediates CRISPR-Cas9 editing. In Lewis lung carcinoma (LLC) tumor mouse models, it leads to the knockdown of vascular endothelial growth factor receptor 2 (VEGFR2), producing antitumor effects. Additionally, in mice with virus-induced lung injury, Si5-N14 facilitates the delivery of fibroblast growth factor-2 (FGF-2) mRNA, promoting vascular repair, oxygenation, and improved lung function. Si5-N14 shows potential for research in tumors, pneumonia, and cardiovascular diseases.