In vitro investigation of anti-cancer activity of ferrocene-functionalized gold nanoparticles

Ferrocene (Fc)-functionalized gold nanoparticles (Fc-GNPs) have been synthesized and tested for anti-tumor activity in breast cancer and normal cell lines MCF-7 and MCF-10a, respectively. Synthesized Fc-GNPs exhibited homogeneous particle distribution as evident from transmission electron microscopy (TEM). Energy dispersive X-ray spectroscopy (EDX) showed the homogenous ligation of Fc on gold nanoparticles. Atomic emission spectroscopy-inductively coupled plasma (AES-ICP) was used to quantify the amount of Fc per GNPs and found to be 84 Fc units per GNPs. Gel electrophoresis and UV–visible (UV–Vis) analysis indicated that Fc-GNPs interacted with DNA. Binding interactions of Fc-GNPs with DNA were investigated using UV–Vis spectrum. Hypochromism and shift towards shorter wavelength was observed with addition of DNA in Fc-GNPs, indicating electrostatic mode of binding of DNA with Fc-capped AuNPs. Drug release experiments performed using dialysis bag method revealed that maximum amount of Fc was released from GNPs in 10–19 h. Cancer cell line treatments showed that Fc-GNPs were comparatively more toxic to MCF-7 (breast cancer cell line) as compared to MCF-10a (breast normal cell line) at 20 μM Fc-GNPs. We did not find any significant differences in Fc and Fc-GNPs treatment in breast normal cell line MCF-10a at 10 μM or 20 μM. However, the toxic effect of the Fc increased sparingly when concentration was raised to 20 μM from 10 μM. Interestingly, Fc-GNPs have higher anti-tumor effect as compared to Fc alone in cancer cell line.