Halloysite Clay Nanotubes: Characterization, Biocompatibility and Use as Drug Carriers

Halloysite nanotubes (HNTs) are efficient nano-containers capable of entrapping a range of active agents within the inner lumen, followed by their retention and slow release. Halloysite is a green environmentally friendly object available in commercial quantities. The lumen of the halloysite tube accomodates globular protein diameters, allowing their entrapment within the inner lumen of the halloysite while retaining their activity for use in biocatalysis. In this work a combination of high resolution imaging technique such as TEM, SEM and SFM have been employed to elucidate the structure. We have investigated their visco-elastic properties by force-indentation measurements and performed cytotoxicity tests utilizing neoplastic cell lines (breast and cervical cancer cells). Furthermore their uptake has been confirmed by Confocal Microscopy after their functionalisation with fluorescence molecules. The results indicate that halloysite nanotubes have been readly uptaken by neoplastic cells and exhibit a high level of biocompatibility.