68Ga-labeled amphiphilic polymer nanoparticles for PET imaging of sentinel lymph node metastasis

Abstract

Precise diagnosis of lymph node metastasis is important for therapeutic regimen planning, prognosis analysis and probably better outcomes for cancer patients. In this work, 68Ga-labeled amphiphilic alternating copolymers nanoparticles with different rigid ligands were synthesized as positron emission tomography (PET) probes for lymph node metastasis imaging. The labeling efficiency and stability of nanoparticles was improved with increased rigidity of coordination unit. PU(68Ga-L-MDI-PEG) nanoparticles (PU(68Ga-L-MDI-PEG) NPs) with the strongest rigidity of coordination unit exhibit the lowest critical micelle concentration, the best 68Ga labeling efficiency and stability. During in vivo lymph node metastasis imaging, PU(68Ga-L-MDI-PEG) NPs led to different accumulations in normal lymph nodes (N-LN) and tumor metastasized sentinel lymph nodes (T-SLN), which resulted in different PET signal presentation, making it feasible to differentiate N-LN from T-SLN. In comparison, small molecule probe 68GaL had poor lymph node accumulation, not only making it difficult to find lymph nodes on PET/CT scan, but also tough to distinguish normal lymph nodes from metastatic ones. Overall, this work provides a reference for design of 68Ga labeled polymeric nanoparticles with high chelation efficiency and stability, as sensitive PET probes for lymph node imaging.

Kinetically inert manganese (II)-based hybrid micellar complexes for magnetic resonance imaging of lymph node metastasis

“…The tumor LN metastasis model was established by subcutaneous injection of 4T1 cells (5 × 10 5 cells in PBS) on the left hind footpad of Balb/c mice [ 4 , 42 ]. Half a month later, the enlargement of LNs was observed by MRI.…”

Polyurethane Nanoparticles as Versatile Tools in Nanomedicine: A Review

“…This study was published as a reference for the creation of very stable and sensitive PET imaging nanoparticle probes with potential use in the imaging of lymph node metastases. 107 PUNPs coated with 68 GaL successfully distinguished normal lymph nodes (N-LN) and tumor metastasized sentinel lymph nodes (T-SLN) with the help of PET imaging, which is not possible with only 68 GaL nanoparticles due to the rapid clearance rate (Figure 9A,C). The maximum standard uptake value of polyurethane-coated 68 GaL nanoparticles in T-SLN was more than that in N-LN (Figure 9E).…”

“…Recently, Chen et al approached coating polyurethane nanoparticles with 68 Ga-labeled small molecule complex ( 68 GaL) for PET imaging. This study was published as a reference for the creation of very stable and sensitive PET imaging nanoparticle probes with potential use in the imaging of lymph node metastases . PUNPs coated with 68 GaL successfully distinguished normal lymph nodes (N-LN) and tumor metastasized sentinel lymph nodes (T-SLN) with the help of PET imaging, which is not possible with only 68 GaL nanoparticles due to the rapid clearance rate (Figure A,C).…”

“…SUV max (E and G) and biodistribution at different time points after injection of PUNPs coated with 68 GaL and only 68 GaL (F and H). From ref . CC BY 4.0.…”