Long-Term In Vivo Biocompatibility of Single-Walled Carbon Nanotubes

Abstract

<jats:title>Abstract</jats:title><jats:p>Over the past two decades, measurements of carbon nanotube toxicity and biodistribution have yielded a wide range of results. Properties such as nanotube type (single-walled vs. multi-walled), purity, length, aggregation state, and functionalization, as well as route of administration, greatly affect both the biocompatibility and biodistribution of carbon nanotubes. These differences suggest that generalizable conclusions may be elusive and that studies must be material- and application-specific. Here, we assess the short- and long-term biodistribution and biocompatibility of a single-chirality DNA-encapsulated single-walled carbon nanotube complex upon intravenous administration that was previously shown to function as an in-vivo reporter of endolysosomal lipid accumulation. Regarding biodistribution and fate, we found bulk specificity to the liver and &gt;90% signal attenuation by 14 days in mice. Using near-infrared hyperspectral microscopy to measure single nanotubes, we found low-level, long-term persistence in organs such as the heart, liver, lung, kidney, and spleen. Measurements of histology, animal weight, complete blood count, and biomarkers of organ function all suggest short- and long-term biocompatibility. This work suggests that carbon nanotubes can be used as preclinical research tools in-vivo without affecting acute or long-term health.</jats:p>

Membrane fusion and drug delivery with carbon nanotube porins

“…Finally, the use of carbon nanomaterials for drug delivery raises some understandable safety concerns. We note, however, that recent studies of the in vivo biocompatibility of short smalldiameter CNTs reported their efficient renal clearance in mice (30,31) and nonhuman primates (32), pointing to the feasibility of using this material for therapeutics development. Further research on the long-term fate and clearance mechanisms of ultrashort carbon nanotubes in the tissues should clarify these important questions.…”

Toward nanobioelectronic medicine: Unlocking new applications using nanotechnology

“…This shows the adaptability of CNTs and how wide a range of medical devices can be made from them while retaining their unique electronic properties. While the biocompatibility of CNTs may still be under investigation, there is now mounting evidence that CNTs can be used safely in medicine and diagnostics including recently published in vivo data that has shown CNTs to be safely used in preclinical research (Aoki & Saito, 2020; Galassi et al, 2020).…”

A perception-based nanosensor platform to detect cancer biomarkers

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