Effect of citrate on the nanocomplex size, charge and characterization of the nanocomplex. Graph showing the hydrodynamic sizes (A) and surface charge (B) of PEI: citrate nanocomplexes formed using different ratio of PEI to citrate measured using zetasizer. C. Titration of different concentration of aptamer and siRNA was carried out and loaded onto 2% agarose gel with ethidium bromide and checked for the retention of the PEI complex on the wells. Lane 3 shows 200nM of aptamer and 200nM of siRNA is required to saturate 0.3μgs of PEI and the next highest concentration of 300nM of aptamer & siRNA respectively had some amount of free siRNA and aptamer (lane 4). Lane 5 & 6 indicates free aptamer and siRNA indicated with red and black arrow respectively. On the right, histogram plot showing Particle size distribution of the PEI-Apt-siRNA nanocomplex. D. Histogram overlay plot showing the percent number distribution of the PEI nanocore alone and PEI-nanocomplex with aptamer and siRNA (hydrodynamic diameter in nm) measured using zetasizer. E. Graph showing the total counts of representative zeta-potential (mV) of the PEI nanocore and the PEI-Apt-siEp nanocomplex. F. TEM images of the PEI nanocomplex left panel showing the uniformity of particle distribution and histogram showing distinct particles with a spherical shape (G). H. Graph showing the percentage cell proliferation upon treating with different concentration from 0.1 to 3 μg/mL of PEI on MCF-7 and WERI-Rb1 cell line till 48 h. Inhibitory effect of PEI on the cell proliferation and mitrochondrial activity was assessed by MTT assay.