ABSTRACT
Objective To develop a cancer cell targeting probe based on silica-coated gold nanorods and investigate its optics properties and its targeting effect on human hepatocellular carcinoma HepG2 cells in vitro.Methods Preparation of gold nanorods (GNRs) by seeded growth method,and then the spherical core-shell silica-coated gold nanorods were successfully prepared by a sol-gel method,finally the GNRs@SiO2 was conjugated with folate (GNRs@SiO2-FA).The characteristics of GNRs@SiO2-FA were studied using transmission electron microscopy,and UV spectra.The cells were divided into 2 groups randomly,adding GNRs@SiO2-FA and GNRs solution respectively at the gold concentration of 40.0 × 10-6,20.0 ×10-6,10.0 × 10-6,5.0 × 10-6,2.5 × 10-6,and the MTT method was applied to detect the absorbance (A value) and study the cytotoxicity of GNRs@SiO2-FA and GNRs.The cells were divided into 2 groups randomly,and incubated with the same concentration of GNRs@SiO2-FA and GNRs@SiO2 solution respectively,at 2,4,8,16,24 h,and the targeting of GNRs@SiO2-FA cellular uptake were detected by ICPMS by observing the process of GNRs@SiO2-FA into the cells by transmission electron microscopy (TEM).The data represented by (-x) ± s ; single factor analysis of variance were compared between the 2 groups ; and the differences were significant when P ＜ 0.05.Results UV spectrum confirmed the successful preparation of GNRs@SiO2-FA.The A value of the same concentration group was variance analysised,and the differences between the 2 groups was statistically significant (all P ＜ 0.01) with the gold element concentration from high to low:F =191.876,265.419,77.987,52.061,18.745.The ICP-MS confirmed GNRs@SiO2-FA could specifically bind with HepG2 cells.GNRs@SiO2 group gold element content at 2,4,8,16,24 h was (256.7±3.3),(602.8±2.4),(1067.1±3.6),(1998.5±4.3),(2078.5±1.3) mg/kg and GNRs@SiO2-FA group was(693.1 ±2.0),(1432.0 ±2.6),(2331.3 ±3.5),(2484.5 ±5.0),(2589.7 ±2.1)mg/kg,and the 2 groups was statistically significant (F =3278.070,34287.199,85434.870,18333.454,42412.973,P ＜0.01).TEM results showed that a small amount of nano probes were in the cytoplasm after cultured with GNRs@SiO2-FA cells 1 h,and that,a lot of probe were in the cytoplasm,4-24 h later,but there was no probe in the nucleus.Conclusion The prepared Folate-conjugated gold nanorods has good performance on biocompatibility and targeting.