Abstract
Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) along with UV-Vis was used to distinguish between structural differences between a normal human breast cell line (MCF-12 F) and a cancerous breast cell line (MCF-7) after both being treated with conjugated gold nanoparticles and unconjugated gold nanoparticles. The MCF-7 cell line possessed a small amount of epidermal growth factor receptors (EGFR) on its cell surface whereas the MCF-12 F cell line did not. The anti-EGFR antibodies blocked the binding of epidermal growth factors to this receptor which plays an important role in the regulation of cell growth, proliferation, and differentiation. The infrared (IR) spectra for both cell lines yield several differences between normal biological samples and cancerous samples. As the malignancy of the sample increases, the peak intensity and wavenumber positions decrease. The same conclusion was drawn from thin-layers of conjugated nanoparticles and nonconjugated nanoparticles. The presence of conjugated nanoparticles increased the peak intensity of the MCF-7 cell line whereas it decreased the peak intensity for the MCF-12 F cell line. UV-Vis was used to show the presence of the anti-EGFR antibodies on the surface of the gold nanoparticles which was 5 nm red shifted compared to the gold nanoparticles solution.
Acknowledgments
This work was supported by grants from the Department of Defense, Breast Cancer Research Program, Grant # W81XWH-10-1-1042 and an undergraduate research program at Albany State University whose support is greatly appreciated. Dr. Seo would like to thank Dr. Minh-Phuong N. Bui, and Dr. Naha for his assistant with the final manuscript. Also, Dr. Seo would like to thank Dr. Jain who provided cell facilities and technical help for cell culturing.