In vivo biodistribution studies and ex vivo lymph node imaging using heavy metal-free quantum dots

• Published in: Biomaterials Vol. 104; pp. 182 - 191
• Main Authors: Yaghini, Elnaz, Turner, Helen D, Le Marois, Alix M, Suhling, Klaus, Naasani, Imad, MacRobert, Alexander J
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01-10-2016; Elsevier Science
• Subjects: Advanced Basic Science; Animals; Breast cancer; Dentistry; Female; Heavy metal-free quantum dots; Indium - chemistry; Luminescent Measurements - methods; Metal Nanoparticles - chemistry; Metals, Heavy; Nanoparticles; Nanotechnology; Photoluminescence; Quantum Dots - chemistry; Rats; Reproducibility of Results; Sensitivity and Specificity; Sentinel lymph node; Sentinel Lymph Node - chemistry; Sentinel Lymph Node - pathology; Tissue Distribution; RES; sentinel lymph node biopsy; ALN; Photoluminescence; QD; SLN; LALN; MA; transmission electron microscopy; polyethylene glycol; dynamic light scattering; indocyanine green; QY; LTLN; LNs; trimethylsilyl; fluorescence lifetime imaging; myristic acid; lymph nodes; thoracic lymph node; Axillary lymph node dissection; ICP-MS; ALND; Sentinel lymph node; DLS; FLIM; left axillary lymph node; Nanoparticles; near-infra red; left thoracic lymph node; charge-coupled device; TLN; light-emitting diode; CCD; Breast cancer; reticuloendothelial system; LED; SLNB; ICG; quantum yield; axillary lymph node; NPs; hydrofluoric acid; Heavy metal-free quantum dots; PEG; NIR; quantum dot; TMS; PL; TEM; inductively coupled plasma-mass spectroscopy; Nanotechnology; HF
• ISSN: 0142-9612; 1878-5905
• DOI: 10.1016/j.biomaterials.2016.07.014

Abstract Quantum dots (QDs) are attractive photoluminescence probes for biomedical imaging due to their unique photophysical properties. However, the potential toxicity of QDs has remained a major obstacle to their clinical use because they commonly incorporate the toxic heavy metal cadmium within the core of the QDs. In this work, we have evaluated a novel type of heavy metal-free/cadmium-free and biocompatible QD nanoparticles (bio CFQD® nanoparticles) with a good photoluminescence quantum yield. Sentinel lymph node mapping is an increasingly important treatment option in the management of breast cancer. We have demonstrated their potential for lymph node mapping by ex vivo imaging of regional lymph nodes after subcutaneous injection in the paw of rats. Using photoluminescence imaging and chemical extraction measurements based on elemental analysis by inductively coupled plasma mass spectroscopy, the quantum dots are shown to accumulate quickly and selectively in the axillary and thoracic regional lymph nodes. In addition, lifetime imaging microscopy of the QD photoluminescence indicates minimal perturbation to their photoluminescence properties in biological systems.