An ionizable cationic lipid (pKa 6.39) has been used in the generation of LNPs for siRNA delivery in vitro and in vivo LNPs containing O12-D3-I3 and encapsulating ferrocene and siRNA targeting Nrf2 or system xc- cystine/glutamate transporter decrease viability of HepG2 cells LNPs containing O12-D3-I3 and an mRNA reporter selectively accumulate in the tumor and liver over the lungs kidneys spleen and heart in mice LNPs containing O12-D3-I3 and encapsulating ferrocene and siRNA targeting Nrf2 or system xc- cystine/glutamate transporter reduce tumor growth and volume in an MCF-7 breast cancer mouse xenograft model LNPs containing O12-D3-I3 and encapsulating siRNA targeting Factor VII decrease hepatocyte Factor VII mRNA levels in mice