Fig. 1.

Characterization of coordination polymer GT/M²⁺ and their efficiency in cytosolic peptide delivery. (a) UV–Vis spectra of GT and GT/M²⁺ complexes prepared at a M²⁺/TPy molar ratio of 1:1 in methanol. (b) Job's plots of GT/M²⁺ coordination polymers in methanol. The x(M²⁺) was defined as the M²⁺:TPy molar ratio, while the △Abs was equal to the absorbance of GT/M²⁺ polymers minus that of free GT in methanol. (c) Size distribution of GT and GT/M²⁺ complexes in deionized water. Mean fluorescence intensity (d) and confocal images (e) of HeLa cells treated with GT, GT/Mn²⁺ and GT/Zn²⁺ complexes with five cargo peptides, respectively. Free peptides and R8-conjugated peptides were tested as negative and positive controls, respectively. The doses of peptide and polymer were fixed at 10 μM and 0.5 μM, respectively. Data were shown as mean ± standard deviation (s.d., n = 3).