Table 1.

Short overview of commonly used siRNA drug-delivery systems

Type	Examples
Drug conjugates	Antibody-siRNA conjugates, polymer-siRNA conjugates, GalNAc-siRNA conjugates, cholesterol-siRNA conjugates
Lipid-based nanocarriers	Liposomes, stealth liposomes, solid-lipid nanoparticles, stable nucleic acid lipid particles, lipid nanoparticles
Polymeric nanocarriers	Nanoparticles based on degradable or non-degradable polymers [chitosan, cyclodextrine, poly(ethylene imine), poly(L-lysine), poly(beta-amino-ester)]; dendrimers [poly(propylene imine), poly(amidoamine)]
Inorganic nanocarriers	Silica nanoparticles, metal/metal oxide nanoparticles (Au, FexOy)
Others	Carbon-based nanoparticles, hydrogels, quantum dots, natural ECVs (exosomes, larger ECVs)

ECVs extracellular vesicles, GalNAc N-acetylgalactosamine, siRNA small interfering RNA