Poly(β-amino amine) cross-linked PEIs as highly efficient gene vectors.

To increase the release of DNA into the cytoplasm and further improve transgene expression of nucleic acid novel polymeric gene carriers were prepared which would be biodegradable under the reducing conditions in the cytoplasm. Disulfide-containing poly(β-amino amine)s were first synthesized and then used to cross-link low molecular weight polyethyleneimine (1800 Da) through Michael addition to obtain SS-PBAA-PEIs as the final gene carriers. The physicochemical characteristics of SS-PBAA-PEI/DNA complexes were characterized. In vitro transfection mediated by the SS-PBAA-PEIs under serum conditions was carried out. Cell uptake of the gene delivery systems was observed by confocal laser scanning microscopy. The results of the physicochemical characterisation demonstrated that the SS-PBAA-PEIs could efficiently condense DNA. In vitro transfection under serum conditions showed that SS-PBAA-PEIs had comparable or even higher transfection efficiencies than 25 kDa PEI. And SS-PBAA-PEIs showed much lower cytotoxicity compared with 25 kDa PEI. In summary, the SS-PBAA-PEIs possess great potential as non-viral gene vectors and exhibit high transfection efficiency under serum conditions.

Deng JZ ，Sun YX ，Wang HY ，Li C ，Huang FW ，Cheng SX ，Zhuo RX ，Zhang XZ ... -  《-》

PEGylated PEI-based biodegradable polymers as non-viral gene vectors.

Novel functional biodegradable gene vectors, poly(L-succinimide)-g-polyethylenimines-g-poly(ethylene glycol) (PSI-g-PEI-g-PEGs) were synthesized by conjugating methoxy poly(ethylene glycol) (mPEG, M(w)=750 Da) to PEI segments (M(w)=800 Da) of PSI-g-PEI. The physicochemical properties of PSI-g-PEI-g-PEGs, including buffering capability, pDNA binding ability, cytotoxicity, zeta potential and the particle size of polymer/pDNA complexes, were explored. The influence of PEGylation was discussed based on a comparative study of PSI-g-PEI-g-PEGs, PSI-g-PEI and PEI25k (M(w)=25 kDa). SEM images revealed that PSI-g-PEI-g-PEG/pDNA particles have a regular shape with the diameter ranging from 70 to 170 nm. PEGylation could suppress the aggregation occurrence between complexes, resulting in a reduction of the polymer/pDNA complex size. PSI-g-PEI-g-PEGs exhibited remarkably lower cytotoxicity compared to PSI-g-PEI and PEI25k. In 293T and HeLa cells, the obtained PSI-g-PEI-g-PEGs showed very high transfection efficiency compared to PEI25k. Fluorescent confocal microscopy demonstrated that PSI-g-PEI-g-PEGs could effectively transport pGL-3 plasmids into the nuclei of HeLa cells. Taking into account the continued high transfection efficacy and decreased toxicity after PEG modification, PSI-g-PEI-g-PEGs show great potential as the non-viral vectors for gene transfection.

Huang FW ，Wang HY ，Li C ，Wang HF ，Sun YX ，Feng J ，Zhang XZ ，Zhuo RX ... -  《-》

Influence of disulfide density and molecular weight on disulfide cross-linked polyethylenimine as gene vectors.

Peng Q ，Hu C ，Cheng J ，Zhong Z ，Zhuo R ... -  《-》

Biotinylated disulfide containing PEI/avidin bioconjugate shows specific enhanced transfection efficiency in HepG2 cells.

Zeng X ，Sun YX ，Zhang XZ ，Zhuo RX ... -  《-》

Synthesis of (Dex-HMDI)-g-PEIs as effective and low cytotoxic nonviral gene vectors.

Sun YX ，Xiao W ，Cheng SX ，Zhang XZ ，Zhuo RX ... -  《-》