Pharmacokinetic Aspects of Carbon Nanotubes: Improving Outcomes of Functionalization

Background: Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. Thanks to their electrical, mechanical and optical properties, they have been widely used for different pharmaceutical, biological and biomedical applications. To understand the biofate of the CNTs in the body, their pharmacokinetic properties should be revealed appropriately. Objective: To review the available literature, regarding the different pharmacokinetic properties including absorption, distribution, metabolism and elimination of the functionalized CNTs. Results: Surface coating or functionalizing the CNTs has huge effects on their pharmacokinetics, ADME properties and also their biodistribution profile. During the metabolism, CNTs could be destroyed directly or their surface functional groups might be removed. Both biliary and renal pathways are known for CNTs elimination. Conclusion: Additional optimization on the CNTs formulation is required to enhance their absorption and bioavailability. Besides, regarding the increased scientific attention towards the CNTs toxicity, it could be suggested that determining the bioavailability of CNTs is a critical parameter to determine the CNTs safety.