Intracellular gallium nitride microrod laser

Abstract

We report laser emission from gallium nitride (GaN) microrods that are introduced into mammalian cells and the application of these microrods for cell labeling. GaN microrods were grown on graphene-coated SiO2/Si substrates by metal-organic vapor phase epitaxy. The GaN microrods are easily detached from the substrates because of the weakness of the van der Waals forces between GaN and graphene. The uptake of microrods into HeLa cells via endocytosis and viability after uptake were investigated. Normal cellular activities, including migration and division, were observed over 2 weeks in culture. Furthermore, the photoluminescence spectra of the internalized microrods exhibited sharp laser emission peaks with a low lasing threshold of 270 kW/cm2.

Effects of surface properties of GaN semiconductors on cell behavior

“…The mechanism may be related to the ordered or disordered steric hindrance related to the surface characteristics, which promotes the binding of proteins onto the surface with unidirectional characteristics of intermolecular spacing affected by the proximity of parallel ridges. In addition, GaN microrods with special structure can be internalized into cells because of their high aspect ratio, and excellent laser signals can be observed under intracellular conditions, which would hold the potential for applications such as cell labeling and tracking [ 54 ].

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