Table 1.

Summary of the advantages of disadvantages of representative types of polyplexes for mRNA delivery

Type of polymer (Examples) a)	Advantages	Disadvantages
PEI	Efficient endosome escape	Charge‐dependent toxicity; poor biocompatibility; lack of biodegradable bonds
Poly(amino acids) (P(Lys), P(Orn), P(Asp))	Biodegradability; endosomal escape capacity	Charge‐dependent toxicity
Polyesters (PLGA, PBAE, PACE)	Biodegradability; facile synthesis monomer availability	No cationic charge; inefficient loading
Natural polymers (Chitosan, Protamine)	Biodegradability; Biocompatibility	Low batch‐to‐batch variability
RAFT polymer (DMAEMA)	Easy production; well‐controlled side chain moieties	Charge‐dependent toxicity
Dendrimers (PAMAM)	Good water solubility; stability against hydrolysis; tunable degradation	Charge‐dependent toxicity especially in high generation of PAMAM; difficulty in synthesizing high molecular weight

^a) The full name of polymers can be found in the main text.