Upconverting Nanoparticles as Optical Sensors of Nano- to Micro-Newton Forces.

ABSTRACT: Mechanical forces affect a myriad of processes, from bone growth to material fracture to touch-responsive robotics. While nano- to micro-Newton forces are prevalent at the microscopic scale, few methods have the nanoscopic size and signal stability to measure them in vivo or in situ. Here, we develop an optical force-sensing platform based on sub-25 nm NaYF₄ nanoparticles (NPs) doped with Yb³⁺, Er³⁺, and Mn²⁺. The lanthanides Yb³⁺ and Er³⁺ enable both photoluminescence and upconversion, while the energetically coupled d-metal Mn²⁺ adds force tunability through its crystal field sensitivity. Using a diamond anvil cell to exert up to 3.5 GPa pressure or ∼10 μN force per particle, we track stress-induced spectral res

SUBMITTER: Lay A 

PROVIDER: S-EPMC6589185 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature