Halloysite clay nanotubes for life sciences applications: From drug encapsulation to bioscaffold

• Published in: Advances in colloid and interface science Vol. 257; pp. 58 - 70
• Main Authors: Santos, Ana C., Ferreira, Carolina, Veiga, Francisco, Ribeiro, António J., Panchal, Abhishek, Lvov, Yuri, Agarwal, Anshul
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.07.2018
• ISSN: 0001-8686; 1873-3727; 1873-3727
• DOI: 10.1016/j.cis.2018.05.007

Natural forming clay halloysite is an emerging nanomaterial carrier for sustained drug delivery. These 50 nm diameter aluminosilicate tubes, with inner - alumina and outer - silica surface layers, can be loaded with 10–30 wt% of drug molecules, DNA and enzymes. The opposite charge of the inner and outer halloysite surface allow for selective drug adsorption inside or outside the clay nanotubes. The drug loaded halloysite enhanced the zeta potential of minus 50–60 mV allowing for stable aqueous nanocolloids. Halloysite nanoformulations provide an extended 10–20 h release profile, and may be functionalized (e.g., clogging tubes' end with polymers extending release time to 1–2 weeks or allowing for triggered release), which renders these clay nanostructures as promising controlled delivery systems. Recent studies demonstrate the potential of abundantly available halloysite clay nanotubes for life science applications, from drug delivery via oral or topical administration, to tissue scaffolds and regenerative medicine, while assessing their cellular internalization, stability, biosafety and biocompatibility are featured. The benefits and limitations of halloysite clay nanotubes are discussed, as well as the directions for future developments. [Display omitted] •Stable colloids of halloysite clay nanotubes were developed as drug delivery systems.•The tubes' lumen can encapsulate and slow release drugs, DNA and proteins.•Halloysite oral or topical administration, tissue scaffolds, implants are described.•Halloysite is safe, biocompatible nanomaterial available for scaled up production.