Au Nanorod Decoration on NaYF4:Yb/Tm Nanoparticles for Enhanced Emission and Wavelength-Dependent Biomolecular Sensing

摘要

We introduce gold nanorods (GNRs) decoration on NaYF4:Yb/Tm upconversion nanocrystals (UCNCs) by functionalizing the UCNCs with polyamidoamine generation 1 (PAMAM Gl) dendrimer, followed by a single-step seed-mediated growth of long-range GNRs to enhance "biological window" upconversion emission, The up-con-version emission of GNR-decorated UCNCs can be enhanced beyond the level typically obtainable using shell-like structures up to 27-fold enhancement. Also, the enhancement can be tuned at different wavelength regions by varying the GNR aspect ratio. The GNR-decorated UCNC is further modified with 2-thiouracil for nonenzymatic detection of uric acid, revealing a detection limit as 1 pM.