Ultra-small dye-doped silica nanoparticles via modified sol-gel technique

R. Riccò*, S. Nizzero, E. Penna, A. Meneghello, E. Cretaio, F. Enrichi

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


In modern biosensing and imaging, fluorescence-based methods constitute the most diffused approach to achieve optimal detection of analytes, both in solution and on the single-particle level. Despite the huge progresses made in recent decades in the development of plasmonic biosensors and label-free sensing techniques, fluorescent molecules remain the most commonly used contrast agents to date for commercial imaging and detection methods. However, they exhibit low stability, can be difficult to functionalise, and often result in a low signal-to-noise ratio. Thus, embedding fluorescent probes into robust and bio-compatible materials, such as silica nanoparticles, can substantially enhance the detection limit and dramatically increase the sensitivity. In this work, ultra-small fluorescent silica nanoparticles (NPs) for optical biosensing applications were doped with a fluorescent dye, using simple water-based sol-gel approaches based on the classical Stöber procedure. By systematically modulating reaction parameters, controllable size tuning of particle diameters as low as 10 nm was achieved. Particles morphology and optical response were evaluated showing a possible single-molecule behaviour, without employing microemulsion methods to achieve similar results. [Figure not available: see fulltext.].

Original languageEnglish
Article number117
JournalJournal of Nanoparticle Research
Issue number5
Publication statusPublished - 1 May 2018


  • Bioimaging applications
  • Biosensing
  • Dye doping
  • Luminescence
  • Silica nanoparticles

ASJC Scopus subject areas

  • Bioengineering
  • Atomic and Molecular Physics, and Optics
  • Chemistry(all)
  • Modelling and Simulation
  • Materials Science(all)
  • Condensed Matter Physics

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