A) Concentration dependent effects of excipients on the uptake of fluorescent, lyophilized MK2i-NPs in HCAVSMCs (n = 3; * p < 0.05, ** p < 0.01, *** p < 0.005, **** p < 0.001) B) Representative histograms of the cellular uptake of freshly prepared and lyophilized MK2i-NP formulations with and without 300 mM lactosucrose in HCAVSMCs. C) Representative confocal microscopy images of the cellular uptake of freshly prepared and lyophilized MK2i-NP formulations with and without 300 mM lactosucrose in HCAVSMCs. NT = no treatment, Ctrl = excipient without polyplexes.