Fig. 2
From: In vivo rendezvous of small nucleic acid drugs with charge-matched block catiomers to target cancers
Dynamic and precise ion-pairing (rendezvous) of an siRNA with free YBCs. a Schematic illustration of the FRET-based analysis of dynamic ion-pairing of siRNA with free YBC (or the exchange reaction between uPIC-forming YBC and free YBC). b FRET analysis of uPIC formation and exchange reaction in buffer solution. c–e IVCLSM images of blood vessels in the mouse ear dermis treated with a stepwise systemic injection of A594-YBC (c), A647-siRNA (d), and N-YBC (e). The scale bars indicate 50 µm. f Time-dependent changes in the FRET signal obtained by quantitative analysis of the IVCLSM images acquired after A594-YBC injection. Left and right arrows indicate the injection of A647-siRNA and non-labelled YBC (N-YBC), respectively. g Sample preparation scheme for the comparative study of uPIC formation under varying conditions. h Hydrodynamic diameters of A647-siRNA complexed with YBC under varying conditions. Data represent the means ± s.d. for five replicate measurements
