A biodegradable poly(ester amine) based on polycaprolactone and polyethylenimine as a gene carrier

Degradable gene delivery systems based on Pluronics-modified low-molecular-weight polyethylenimine: preparation, characterization, intracellular trafficking, and cellular distribution

“…20 Degradation study and resistance to nuclease degradation Degradation of gene delivery polymers in vivo is important for safe and efficient gene delivery, because the appropriate degradation of the polymer could reduce cytotoxicity and facilitate elimination through the excretion pathway in vivo. 21,22 Nondegradable PEI may accumulate in vivo because of a lack of degradation or excretion pathways, causing potential cytotoxicity. Therefore, it is expected that ester bonds in these polymers are susceptible to hydrolysis in physiological conditions, forming poloxamer oligomers and low-molecular-weight polyethylene.…”

Novel degradable oligoethylenimine acrylate ester-based pseudodendrimers for in vitro and in vivo gene transfer

“…2,3 Thus, an excellent in vivo transfection activity at low toxicity should be the major considerations regarding the design of novel nonviral gene delivery devices. Recently, many degradable polymers have been generated, [4][5][6][7][8][9][10][11][12][13][14] aiming to reduce the toxicity profile while maintaining transfection efficiency levels comparable to nondegradable gene vectors like polyamidoamine dendrimers [15][16][17] or optimized polyethylenimines (PEIs). 18,19 For example, promising results have been obtained 6,9 by coupling low molecular weight oligoethylenimine 800 Da (OEI) with short diacrylate linkages, thus combining the beneficial low cytotoxic properties of OEI with the higher transfection efficiency of higher molecular weight PEIs.…”

Endosomal Escape Pathways for Non-Viral Nucleic Acid Delivery Systems

“…Modified versions of PEI, such as low molecular weight PEI (LMW-PEI) (Kunath, von Harpe et al 2003) and low branching degree PEI (Fischer, Bieber et al 1999), have been investigated to reduce the toxicity of the polymers without compromising their pH buffering capacity (Kunath, von Harpe et al 2003;Arote, Kim et al 2007). …”