In vivo biodistribution and toxicology studies of cadmium-free indium-based quantum dot nanoparticles in a rat model

• Published in: Nanomedicine Vol. 14; no. 8; pp. 2644 - 2655
• Main Authors: Yaghini, Elnaz, Turner, Helen, Pilling, Andrew, Naasani, Imad, MacRobert, Alexander J.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-11-2018; Elsevier
• Subjects: Animals; Biodistribution; Cadmium; Cadmium-free quantum dots; Female; Indium - pharmacokinetics; Indium - toxicity; Liver - drug effects; Liver - metabolism; Models, Animal; Nanoparticles; Nanoparticles - metabolism; Nanoparticles - toxicity; Quantum Dots - metabolism; Quantum Dots - toxicity; Rats; Tissue Distribution; Toxicity Tests; Toxicology; Nanoparticles; Toxicology; Cadmium-free quantum dots; Biodistribution
• ISSN: 1549-9634; 1549-9642
• DOI: 10.1016/j.nano.2018.07.009

Quantum dot (QD) nanoparticles are highly promising contrast agents and probes for biomedical applications owing to their excellent photophysical properties. However, toxicity concerns about commonly used cadmium-based QDs hinder their translation to clinical applications. In this study we describe the in vivo biodistribution and toxicology of indium-based water soluble QDs in rats following intravenous administration. The biodistribution measured at up to 90 days showed that QDs mainly accumulated in the liver and spleen, with similar elimination kinetics to subcutaneous administration. Evidence for QD degradation in the liver was found by comparing photoluminescence measurements versus elemental analysis. No organ damage or histopathological lesions were observed for the QDs treated rats after 24 h, 1 and 4 weeks following intravenous administration at 12.5 mg/kg or 50 mg/kg. Analysis of serum biochemistry and complete blood counts found no toxicity. This work supports the strong potential of indium-based QDs for translation into the clinic.
Quantum dot (QD) nanoparticles are emerging as a new class of fluorescence probes for biomedical applications. However, toxicity concerns of cadmium-based QDs hinder their translation to clinical settings. In this study we systemically investigated the in vivo biodistribution and toxicology of cadmium-free indium-based QDs in a rat model. Following intravenous injection the majority of QDs were accumulated in the liver and spleen and were excreted from the body over a period of ninety days as evidenced by elemental analysis. Comprehensive in vivo toxicology studies using histological assessments, hematological and biochemical markers demonstrated the biocompatibility of indium-based QDs for biomedical applications. [Display omitted]