Dd2 600 mhz ft nmr

To confirm of chemical structures of GC-DTA NPs and GC-DBA NPs, they were freshly dissolved in DMSO-d₆ / D₂O (1:1 v/v) and characteristic peaks were measured by 600 MHz ¹H-NMR (DD2 600 MHz FT NMR, Agilent Technologies, USA). The structure of GC-DTA NPs and GC-DBA NPs were analyzed using characteristic peaks at 2.4-2.6 ppm (-CH3 at DTA and DBA) and 3.6-3.8 ppm (GC) and 7.6-7.9 ppm (-CH at DBA) (Figure 2a). The amount of iodine in GC-DTA NPs were determined using the inductively coupled plasma optical emission spectroscopy (ICP-AES, 710-ES, Varian, Australia). To analyze the size distribution and zeta-potential (ξ) of GC-DTA NPs, GC-DBA-NPs, GC-DTA-PFP NPs and GC-DBA-PFP NPs, 1 mg of GC-DTA NPs, GC-DBA-NPs, GC-DTA-PFP NPs and GC-DBA-PFP NPs were dispersed in 1 ml of phosphate buffered saline (PBS, pH 7.4) and were measured size with zeta-potential using Zeta-sizer (Nano ZS, Malvern, UK) (Figure 2b). The morphologies of GC-DTA NPs, GC-DBA-NPs, GC-DTA-PFP NPs and GC-DBA-PFP NPs were observed using transmission electron microscope (TEM, Tecnai F20, FEI, Netherlands) at an accelerating voltage of 200 keV (Figure 2c). For TEM images, all samples were dispersed in distilled water and were negative stained by 2 % uranyl acetate.