C60-fullerenes as Drug Delivery Carriers for Anticancer Agents: Promises and Hurdles

Abstract

Background: C60-fullerenes (CFs) constitute a carbon-allotropic family with cage-like fused-ring structure, comprising of 20 hexagons and 12 pentagons. Since discovery in 1985, CFs attracted the scientists from various strata for unique properties like tensile strength, nanometeric size, symmetric nature, thermal and photo conductivity, chemical tailoring opportunities and drug loading capabilities. Surprisingly, CFs are also established to possess antiviral, neuroprotective, antiinflammatory, MRI contrast and antioxidant properties. Though extensively explored for chemical modifications and therapeutic benefits, CFs and derivatives also offer immense promises in drug delivery, especially to the cancerous cells.

Objective: The present review is an attempt to highlight the promises of CFs in drug delivery, esp. of anticancer agents. The review also analyzes the safety concerns of CF-based drug delivery and attempts to discuss the promises and challenges in the light of preclinical and clinical data.

Methods: The raw material (research/review articles) for the manuscript was collected from Pubmed, Google scholar and Scopus and the keywords used were fullerenes, nanotechnology, nanomedicine, functionalization, safety, drug delivery and biomedical applications.

Conclusion: The drug release rate controlling behavior, higher drug loading, immuno-neutrality, substantial biocompatibility, capability to bypass mononuclear phagocytic system, long circulating nature and tissue extraction by virtue of enhanced permeability and retention effect are the major promises of these nanocarriers. On the other hand, the concerns like elimination from the biological system, anticipated tissue toxicity, stability of the final product, sterility issues and commercial viability pose challenges in proper utilization of CFs as ideal drug delivery carriers. However, a few commercial products based on CFs with human safety evidences provide a ray of hope.

Keywords: Bioavailability; buckminster fullerene; functionalization; safety; solubility.