Authors: Ekaterina I. Galanzha, Robert Weingold, Dmitry A. Nedosekin, Mustafa Sarimollaoglu, Jacqueline Nolan, Walter Harrington, Alexander S. Kuchyanov, Roman G. Parkhomenko, Fumiya Watanabe, Zeid Nima, Alexandru S. Biris, Alexander I. Plekhanov, Mark I. Stockman, & Vladimir P. Zharov
Publication: Nature Communications, volume 8, Article number: 15528 (2017)
Understanding cell biology greatly benefits from the development of advanced diagnostic probes. Here we introduce a 22-nm spaser (plasmonic nanolaser) with the ability to serve as a super-bright, water-soluble, biocompatible probe capable of generating stimulated emission directly inside living cells and animal tissues. We have demonstrated a lasing regime associated with the formation of a dynamic vapour nanobubble around the spaser that leads to giant spasing with emission intensity and spectral width >100 times brighter and 30-fold narrower, respectively, than for quantum dots. The absorption losses in the spaser enhance its multifunctionality, allowing for nanobubble-amplified photothermal and photoacoustic imaging and therapy. Furthermore, the silica spaser surface has been covalently functionalized with folic acid for molecular targeting of cancer cells. All these properties make a nanobubble spaser a promising multimodal, super-contrast, ultrafast cellular probe with a single-pulse nanosecond excitation for a variety of in vitro and in vivo biomedical applications.