Figure 8 Magnetization curve. (a) Fe3O4 (b) Fe3O4@SiO2, and (c) Fe3O4@SiO2-OCMCS-FA nanovehicle at 300 K. In vitro targeting of nanovehicle The ability of nanoparticles to target specific locations is one of the most important factors for their prospective application in drug delivery and biomedicine. To investigate the uptake possibility of Fe3O4@SiO2-OCMCS-FA, CLSM was applied to trace the process of this nanovehicle. Therefore, RB is labeled on the surface of the nanovehicle to distinguish it. To explore the practical application of this nanovehicle in the targeting of tumor cells, the

particles were incubated in physiological conditions with HeLa cells bearing the over-expressed Selleck LY2606368 folate receptor. Figure 9 shows DAPI, LBH589 supplier RB, and merged images of HeLa cells incubated with RBFe3O4@SiO2 (20 μg mL-1, control) and RBFe3O4@SiO2-OCMCS-FA (20 μg mL-1) for 2 h. Interestingly,

even at the very low concentration, the CLSM images show that the RBFe3O4@SiO2-OCMCS-FA nanoparticles could be taken up by HeLa cells within a short period as manifested by the appearance of spot-like red fluorescence in cells (Figure 9b), while untreated RBFe3O4@SiO2 showed negligible background fluorescence under similar imaging conditions (Figure 9a). The merge of the bright-field and fluorescent images further demonstrates that the luminescence is strongly correlated with the intracellular location (Figure 9b) suggesting the feasibility and efficiency of the nanoparticles for

anticancer drug delivery into cancer cells. In addition, the fluorescent image shown in Figure 9b also testifies that the nanovehicle was mainly distributed in the cytoplasm after cellular uptake. The confocal laser scanning microscope observation confirms that the nanovehicle could be effectively taken up by the HeLa cells as the folate modified. Figure 9 Confocal laser scanning microscope images of subcellular Flavopiridol (Alvocidib) localization. (a) RBFe3O4@SiO2 and (b) RBFe3O4@SiO2-OCMCS-FA after 2 h of incubation with HeLa cells. Nuclei were stained with DAPI. To further reveal that the nanovehicle was internalized in HeLa cells rather than being bound to the cell surface, bio-TEM was used to analyze the nanovehicle-treated cells. Unlike the untreated cells (Figure 10a), some aggregates of nanovehicles were observed as black patches inside the cell cytoplasm which maintained their core-shell structure (Figure 10b and the inset), while no nanovehicle was found in the nucleus which coincided with the results of CLSM. Based on the cell morphology, it is plausible that the nanovehicle accumulates on the membrane (Figure 10c) by the high specific interaction between folic acid on the nanovehicle and FR on HeLa cells which may increase the uptake through folate receptor-mediated endocytosis.