Spatial Dopant Separation using Core-Shell Architecture For Upconversion Luminescent Enhancement in the Erbium-Doped System

Invention Summary:

Upconversion nanoparticles (UCNPs) have gained increasing attention for various biomedical applications due to their high photostability, low autofluorescent background, and deep tissue penetration; however, UCNPs also suffer from low emission intensities due to undesirable energy back-transfer. Further, the use of high-power density excitations at 980 nm may cause serious overheating and thus cellular damages under continuous irradiation.

Researchers at Rutgers University have developed a single-crystal core–shell–shell “sandwich” structured UCNP that eliminates energy back-transfer to yield bright visible emissions using low power density excitations. These UCNPs show a remarkable enhancement of luminescent output relative to conventional β-NaYF4:Yb,Er co-doped UCNPs and β-NaYF4:Yb,Er@NaYF4:Yb “active shell” structured UCNPs. As a proof-of-concept, this advanced core–shell–shell UCNP is subsequently used to develop a highly sensitive biosensor for the ultrasensitive detection of dopamine released from stem cell-derived dopaminergic-neurons.

Given the challenges of in situ detection of biomolecules, this UCNP-based NIR biosensor presents a unique tool for investigating single-cell mechanisms and understanding their roles in biological processes.

Market Applications:

  • Bioimaging
  • Biosensing probe
  • Medical imaging contrast agent


  • Low thermal toxicity
  • Efficient excitation-emission conversion at low power density
  • High signal to noise ratio
  • No photobleaching
  • Modular functionalization for diverse biomolecule detection

Intellectual Property & Development Status: Patent pending.

  • Patent pending. Available for licensing and/or research collaboration.


  • NIR Biosensing of Neurotransmitters in Stem Cell-Derived Neural Interface Using Advanced Core-Shell Upconversion Nanoparticles.Rabie H, Zhang Y, Pasquale N, Lagos MJ, Batson PE and Lee K-B. Advanced Materials 2019, 31, 1806991.
Patent Information:
Lisa Lyu
Assistant Director
Rutgers, The State University of New Jersey
Sensors & Probes