title: Promoting cell proliferation using water dispersible germanium nanowires.
abstract: Group IV Nanowires have strong potential for several biomedical applications. However, to date their use remains limited because many are synthesised using heavy metal seeds and functionalised using organic ligands to make the materials water dispersible. This can result in unpredicted toxic side effects for mammalian cells cultured on the wires. Here, we describe an approach to make seedless and ligand free Germanium nanowires water dispersible using glutamic acid, a natural occurring amino acid that alleviates the environmental and health hazards associated with traditional functionalisation materials. We analysed the treated material extensively using Transmission electron microscopy (TEM), High resolution-TEM, and scanning electron microscope (SEM). Using a series of state of the art biochemical and morphological assays, together with a series of complimentary and synergistic cellular and molecular approaches, we show that the water dispersible germanium nanowires are non-toxic and are biocompatible. We monitored the behaviour of the cells growing on the treated germanium nanowires using a real time impedance based platform (xCELLigence) which revealed that the treated germanium nanowires promote cell adhesion and cell proliferation which we believe is as a result of the presence of an etched surface giving rise to a collagen like structure and an oxide layer. Furthermore this study is the first to evaluate the associated effect of Germanium nanowires on mammalian cells. Our studies highlight the potential use of water dispersible Germanium Nanowires in biological platforms that encourage anchorage-dependent cell growth.
authors.affiliation: Department of Life Sciences, and Materials and Surface Science Institute, University of Limerick, Limerick, Ireland.
authors.forename: Michael
authors.initials: M
authors.lastname: Bezuidenhout
authors.affiliation: Materials and Surface Science Institute and Department of Chemical and Environmental Sciences, University of Limerick, Limerick, Ireland.
authors.forename: Pai
authors.initials: P
authors.lastname: Liu
authors.affiliation: Materials and Surface Science Institute and Department of Chemical and Environmental Sciences, University of Limerick, Limerick, Ireland.
authors.forename: Shalini
authors.initials: S
authors.lastname: Singh
authors.affiliation: Department of Life Sciences, and Materials and Surface Science Institute, University of Limerick, Limerick, Ireland.
authors.forename: Maeve
authors.initials: M
authors.lastname: Kiely
authors.affiliation: Materials and Surface Science Institute and Department of Chemical and Environmental Sciences, University of Limerick, Limerick, Ireland.
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Ryan
authors.affiliation: Department of Life Sciences, and Materials and Surface Science Institute, University of Limerick, Limerick, Ireland; Stokes Institute, University of Limerick, Limerick, Ireland.
authors.forename: Patrick A
authors.initials: PA
authors.lastname: Kiely
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D018929:Cell Culture Techniques; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects*; D005857:Germanium / Q000494:pharmacology*; D018698:Glutamic Acid / Q000494:pharmacology*; D006801:Humans; D061986:MCF-7 Cells; D051379:Mice; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053770:Nanowires
chemical_list: D005857:Germanium; D018698:Glutamic Acid