Folate functionalized silicon nanowires with highly enhanced adhesion to cancer cells

Abstract In this study, we implemented a functionalization process on the surface of silicon nanowires (SiNWs) which were fabricated by chemical vapour deposition (CVD) method in a low‐pressure CVD (LPCVD) chamber. Surface functionalization was carried out in three stages: hydroxylation of the surface with piranha solution, silanization with a solution of 3‐Aminopropyl triethoxysilane (APTES) in n‐hexane, and finally functionalization with folic acid as a detection agent. Optical spectroscopy and electron microscopy techniques were used to experimentally characterize materials. Surface functionalization was evaluated using Attenuated Total Reflectance Fourier‐Transform Infrared spectroscopy (FTIR‐ATR), Field Emission Scanning Electron Miscoscopy (FESEM), and Transmission Electron Microscopy (TEM). Cell adhesion to functionalized and non‐functionalized silicon nanowires was compared; a cell assay analysis on lung metastatic cells was conducted. Lung cancer metastatic QUDB cells were seeded on a SiNWs surface in RPMI1640 complete medium. To evaluate the adhesion of cancer cells to these surfaces FESEM imaging was used. The number of cancer cells trapped on the folic acid functionalized SiNWs was found to be approximately 3 times higher than that of the non‐functionalized ones.