Tiny intracellular lasers

Fikouras, A. H. et al. Nat. Commun. 9, 4817 (2018).

Fluorescent probes are widely used in biological imaging, but they are not ideal for all applications because they often have broad spectra, which limits multiplexing, and they can suffer from limited brightness and photostability. Intracellular lasers have recently been introduced that have narrow emission spectra and give bright and stable signal; however, these are larger than the average cell nucleus, which limits their utility. Fikouras et al. have developed semiconductor nanodisk lasers with volumes 1,000-fold smaller than the eukaryotic nucleus. Their small size is made possible by the large optical gain and high refractive index of their gallium indium phosphide/aluminum gallium indium phosphide multi-quantum well structure. Their lasing wavelength is size dependent, which makes the development of different-colored lasers straightforward. The nanodisk lasers were used as probes in several mammalian cell types.