10 research outputs found
Photoacoustic Sentinel Lymph Node Imaging with Self-Assembled Copper Neodecanoate Nanoparticles
Photoacoustic tomography (PAT) is emerging as a novel, hybrid, and non-ionizing imaging modality because of its satisfactory spatial resolution and high soft tissue contrast. PAT combines the advantages of both optical and ultrasonic imaging methods. It opens up the possibilities for noninvasive staging of breast cancer and may replace sentinel lymph node (SLN) biopsy in clinic in the near future. In this work, we demonstrate for the first time that copper can be used as a contrast metal for near-infrared detection of SLN using PAT. A unique strategy is adopted to encapsulate multiple copies of Cu as organically soluble small molecule complexes within a phospholipid-entrapped nanoparticle. The nanoparticles assumed a size of 80–90 nm, which is the optimum hydrodynamic diameter for its distribution throughout the lymphatic systems. These particles provided at least 6-fold higher signal sensitivity in comparison to blood, which is a natural absorber of light. We also demonstrated that high SLN detection sensitivity with PAT can be achieved in a rodent model. This work clearly demonstrates for the first time the potential use of copper as an optical contrast agent
Non-linear magnons and exchange Hamiltonians of delafossite proximate quantum spin liquids
Quantum spin liquids (QSL) are theoretical states of matter with long-range
entanglement and exotic quasiparticles. However, they generally elude
quantitative theory, rendering their underlying phases mysterious and hampering
efforts to identify experimental QSL states. Here we study triangular lattice
resonating valence bond QSL candidate materials KYbSe and NaYbSe. We
measure the magnon modes in their 1/3 plateau phase, where quantitative theory
is tractable, using inelastic neutron scattering and fit them using nonlinear
spin wave theory. We also fit the KYbSe heat capacity using high
temperature series expansion. Both KYbSe fits yield the same magnetic
Hamiltonian to within uncertainty, confirming previous estimates and showing
the Heisenberg to be an accurate model for these materials. Most
importantly, comparing KYbSe and NaYbSe shows that smaller -site
Na ion has a larger ratio. However, hydrostatic pressure applied
to KYbSe increases the ordering temperature (a result consistent with
density functional theory calculations), indicating that pressure decreases
. These results show how periodic table and hydrostatic pressure can
tune the YbSe materials in a controlled way.Comment: 7 pages, 7 figures; 4 pages and 7 additional figures of supplemental
informatio
Photoacoustic Sentinel Lymph Node Imaging with Self-Assembled Copper Neodecanoate Nanoparticles
Photoacoustic tomography (PAT) is emerging as a novel, hybrid, and non-ionizing imaging modality because of its satisfactory spatial resolution and high soft tissue contrast. PAT combines the advantages of both optical and ultrasonic imaging methods. It opens up the possibilities for noninvasive staging of breast cancer and may replace sentinel lymph node (SLN) biopsy in clinic in the near future. In this work, we demonstrate for the first time that copper can be used as a contrast metal for near-infrared detection of SLN using PAT. A unique strategy is adopted to encapsulate multiple copies of Cu as organically soluble small molecule complexes within a phospholipid-entrapped nanoparticle. The nanoparticles assumed a size of 80–90 nm, which is the optimum hydrodynamic diameter for its distribution throughout the lymphatic systems. These particles provided at least 6-fold higher signal sensitivity in comparison to blood, which is a natural absorber of light. We also demonstrated that high SLN detection sensitivity with PAT can be achieved in a rodent model. This work clearly demonstrates for the first time the potential use of copper as an optical contrast agent