Fig. 2: Characterization of G3@SeHANs.

a SEM imaging of SeHANs before and after coating with PAMAM-G3. b–d XPS spectra. The N 1s photoelectron peak (398.9 eV) is present only in G3@SeHANs; Se 3d peaks (58.9 eV) are present in both SeHANs and G3@SeHANs. Representative images were from 3 independent experiments. e FTIR spectra. Both SeHANs and G3@SeHANs exhibit characteristic phosphate bands at 562, 603, and 1030 cm⁻¹, and bands corresponding to O-Se-O bending vibration (783 cm⁻¹) and hydroxyl groups (3570 cm⁻¹). Peaks due to amino stretching vibration (3283 cm⁻¹) and bending vibration of the amide N-H bond (1649 cm⁻¹) are present only in G3@SeHANs. f The thermal decomposition rate of the nanoparticles changes after coating with PAMAM-G3. g Zeta potential of SeHANs and G3@SeHANs. Data are means ± SEM; differences were assessed by two-tailed Student’s t-test (n = 5) (P < 0.0001). h BET analysis of SeHANs and G3@SeHANs. i Size measurement of SeHANs and G3@SeHANs. Data are means ± SEM; differences were assessed by two-tailed Student’s t-test (n = 5) (P = 0.3898). j XRD analysis of SeHANs and G3@SeHANs. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001.