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.
C-TRAIN and Division of Cardiology, Washington University School of Medicine, 4320 Forest Park Avenue, St. Louis, Missouri 63108, United States. dipanjan@wustl.edu
Dipanjan
D
Pan
Xin
X
Cai
Ceren
C
Yalaz
Angana
A
Senpan
Karthik
K
Omanakuttan
Samuel A
SA
Wickline
Lihong V
LV
Wang
Gregory M
GM
Lanza
D000818:Animals; D003300:Copper / Q000737:chemistry*; D003652:Decanoic Acids / Q000737:chemistry*; D008198:Lymph Nodes / Q000378:metabolism*; D057054:Molecular Imaging / Q000379:methods*; D015335:Molecular Probes / Q000737:chemistry / Q000378:metabolism; D053758:Nanoparticles / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D061088:Photoacoustic Techniques / Q000379:methods*; D051381:Rats
D003652:Decanoic Acids; D015335:Molecular Probes; D009942:Organometallic Compounds; D003300:Copper; C011944:neodecanoic acid