Fig. 1. Polymer design and transfection efficiency in MCF-7 cells. (a) Synthesis of systematic dendronised polymer design and architecture; polymers are random statistical copolymers of HEMA and GMA where x = mol% GMA. Poly(amido amine) dendrons of different generation are clicked onto the linear polymer backbone. Reaction conditions: (i) NaN3, NH4Cl, DMF, 60 °C, 72 h; (ii) PMDETA, CuBr, DMF, r.t., 72 h; (iii) ethylenediamine, MeOH, 0 °C. (b and c) Representations of polymers prepared in this work. Schematics demonstrate how flexibility is systematically altered by varying dendron generation and dendron density independently. (d) Transfection efficiency of polymers delivering EGFP-encoding plasmid to MCF-7 cells at an N/P ratio of 10. Polymer 10c (x = 0.17, G5 PAMAM dendron) significantly outperformed traditional G5 PAMAM dendrimer (p ≤ 0.0001).
