Abstract: The present invention addresses the problem of providing lipid nanoparticles which function as gene transfer carriers capable of selective transfer to the liver or spleen. Lipid nanoparticles which contain a pH-sensitive cationic lipid represented by formula (I) [a represents an integer of 3-5; b represents 0 or 1; R1 and R2 each independently represent a group represented by general formula (A) (R11 and R12 each independently represent a linear or branched C2-15 alkyl group; c represents 0 or 1; v represents an integer of 4-12); and X represents a group represented by general formula (B)(d represents an integer of 0-3; and R3 and R4 each independently represent a C1-4 alkyl group or C2-4 alkenyl group, while R3 and R4 may form a 5- to 7-membered non-aromatic heterocycle) or represents a 5- to 7-membered non-aromatic heterocyclic group]. (I) (R1)(R2)C(OH)—(CH2)a-(O—CO)b-X. (A): (R11)(R12)—CH—(CO—O)c-(CH2)v-. (B):—(CH2)d-N(R3)(R4).

Abstract: The present invention addresses the problem of providing lipid nanoparticles which function as gene transfer carriers capable of selective transfer to the liver or spleen. Lipid nanoparticles which contain a pH-sensitive cationic lipid represented by formula (I) [a represents an integer of 3-5; b represents 0 or 1; R1 and R2 each independently represent a group represented by general formula (A) (R11 and R12 each independently represent a linear or branched C2-15 alkyl group; c represents 0 or 1; v represents an integer of 4-12); and X represents a group represented by general formula (B)(d represents an integer of 0-3; and R3 and R4 each independently represent a C1-4 alkyl group or C2-4 alkenyl group, while R3 and R4 may form a 5- to 7-membered non-aromatic heterocycle) or represents a 5- to 7-membered non-aromatic heterocyclic group]. (I) (R1)(R2)C(OH)—(CH2)a—(O—CO)b—X. (A): (R11)(R12)—CH—(CO—O)c—(CH2)v-. (B):—(CH2)d-N(R3)(R4).