Figure 3.

Preparation and characterization of PSP-^DPMI spherical shell. (A) The strategy for the preparation of PSP-^DPMI. Characterization of synthesized ^DPMI (B), PSP-NHS (C), and PSP-^DPMI (D) by HPLC and ESI-MASS. (E) Transmission electron micrograph (TEM) of PSP-^DPMI at pH 7.4 and the light picture of PSP-^DPMI (0.2 mg/mL) solution. (F) Hydrodynamic distributions of PSP-^DPMI (at pH 7.4 and pH 6.5), which were measured by DLS. (G) The surface charge of PSP-^DPMI (at pH 7.4 and pH 6.5), which were measured in PBS buffer by DLS at 37 °C. (H) Transmission electron micrograph (TEM) of PSP-^DPMI at pH 6.5 and the light picture of PSP-^DPMI (0.2 mg/mL) solution.