pH‐Dependent Structural Changes in Polyethyleneimine Affect its Gene Transfection Efficiency (Small 33/2025)

Polyethyleneimine In article number 2411293, Kamendra P. Sharma, Shobhna Kapoor, and co-workers show that time-dependent self-assembly of polyethyleneimine (PEI) chains conditioned at pH 3.0 leads to hierarchical microstructures that impede its gene transfection. However, PEI, transitioned through pH 1.4, provides efficient transfection. This work highlights how the level of protonation, the subsequent charge density variations and the resultant microstructure of PEI chains facilitates or hinders gene transfection.