Fig. 5
a Observation of nHAP presence (small black spots showed by arrows) under transmission electron microscopy (TEM) with magnification of 25,000 times after in vivo intra-arterial injection of polyplex/lipiodol emulsion to VX2 tumor-bearing Rabbits: no nHAP deposit in VX2 tumor cell (TN) and normal liver cell (LN) of PEGFP-C2-wt-P53/lipiodol group. nHAP deposit in both VX2 tumor cell (TC) and normal liver cell (LC) of U-nanoplex/lipiodol group. nHAP deposit in cytoplasm of normal liver cell (LD) but VX2 tumor cell (TD) of Ca-nanoplexCa-nanoplex/lipiodol group. nHAP can selectively deposit in cytoplasm of VX2 tumor cell (TE) but normal liver cell (LE) of Pll-nanoplex/lipiodol group. b Semi-qualitative energy dispersive spectroscopy (EDS) spectra of all the tissues above in Fig. 5a were investigated under scanning electron microscopy (SEM): As presented, their spectra have been overlapped except in the region of 2.010 and 3.692 keV which represent the calcium and phosphorus element respectively. The peak area of calcium and phosphorus element can be seen in the samples of TC, LC, LD, TE but LN, TN, TD, LE. The main components of nHAp were calcium and phosphorus in the molar ratio Ca/P around of 2.0, which is similar to the estimated Ca/P molar ratio of TC, LC, LD, TE . In contrast, the Ca/P molar ratios of LN, TN, TD, LE had similar consequences around 0.6. The EDS analysis further confirm presence of nHAPs shown in Fig. 5a. Therefore, the existence of nHAP was confirmed in the samples of TC, LC, LD, TE but LN, TN, TD, LE