Multimodal near-infrared-emitting PluS Silica nanoparticles with fluorescent, photoacoustic, and photothermal capabilities

Stefania Biffi, Luca Petrizza, Chiara Garrovo, Enrico Rampazzo, Laura Andolfi, Pierangela Giustetto, Ivaylo Nikolov, Gabor Kurdi, Miltcho Boyanov Danailov, Giorgio Zauli, Paola Secchiero, Luca Prodi

Research output: Contribution to journalArticlepeer-review


Purpose: The aim of the present study was to develop nanoprobes with theranostic features, including – at the same time – photoacoustic, near-infrared (NIR) optical imaging, and photothermal properties, in a versatile and stable core–shell silica-polyethylene glycol (PEG) nanoparticle architecture. Materials and methods: We synthesized core–shell silica-PEG nanoparticles by a one-pot direct micelles approach. Fluorescence emission and photoacoustic and photothermal properties were obtained at the same time by appropriate doping with triethoxysilane-derivatized cyanine 5.5 (Cy5.5) and cyanine 7 (Cy7) dyes. The performances of these nanoprobes were measured in vitro, using nanoparticle suspensions in phosphate-buffered saline and blood, dedicated phantoms, and after incubation with MDA-MB-231 cells. Results: We obtained core–shell silica-PEG nanoparticles endowed with very high colloidal stability in water and in biological environment, with absorption and fluorescence emission in the NIR field. The presence of Cy5.5 and Cy7 dyes made it possible to reach a more reproducible and higher doping regime, producing fluorescence emission at a single excitation wavelength in two different channels, owing to the energy transfer processes within the nanoparticle. The nanoarchitecture and the presence of both Cy5.5 and Cy7 dyes provided a favorable agreement between fluorescence emission and quenching, to achieve optical imaging and photoacoustic and photothermal properties. Conclusion: We obtained rationally designed nanoparticles with outstanding stability in biological environment. At appropriate doping regimes, the presence of Cy5.5 and Cy7 dyes allowed us to tune fluorescence emission in the NIR for optical imaging and to exploit quenching processes for photoacoustic and photothermal capabilities. These nanostructures are promising in vivo theranostic tools for the near future.

Original languageEnglish
Pages (from-to)4865-4874
Number of pages10
JournalInternational Journal of Nanomedicine
Publication statusPublished - Sep 22 2016


  • Dye-doped nanoparticles
  • NIR imaging
  • Optical imaging
  • PEGylated nanoparticles
  • Photoacoustic imaging
  • Photothermal therapy

ASJC Scopus subject areas

  • Bioengineering
  • Biophysics
  • Biomaterials
  • Drug Discovery
  • Organic Chemistry


Dive into the research topics of 'Multimodal near-infrared-emitting PluS Silica nanoparticles with fluorescent, photoacoustic, and photothermal capabilities'. Together they form a unique fingerprint.

Cite this