Self-Assembled Structures of Halloysite Nanotubes: Towards the Development of High-performance Biomedical Materials
Halloysite nanotubes (HNTs), 1D natural tubular nanoparticles, exhibit high aspect ratio, empty lumen, high adsorption ability, good biocompatibility, and high biosafety, which have attracted the researchers’ attentions in the application of biomedical area. HNTs can be readily dispersed in water due to their negatively charged surface and good hydrophilicity. The unique rod-like structure and surface properties make HNTs possessing assembly ability into ordered hierarchical structures. In this review, the self-assembly approaches of HNTs including evaporation induced self-assembly by a “coffee-ring” mechanism, shear force induced self-assembly, and electric field force induced self-assembly were introduced. In addition, HNTs self-assembly on polymeric substrates and biological substrates including hair, cells, and fish embryos were discussed. These assembly processes are related to noncovalent interactions such as the electrostatic, hydrogen bonding, van der Waals forces or electron-transfer reactions. Moreover, the applications of self-assembly HNTs pattern in biomedical area such as capture of circulating tumor cells, guiding cells orientation growth, controlling cell germination, delivery of drug or nutrient were discussed and highlighted. Finally, challenges and future directions of assembly of HNTs are introduced. This review will inspire researchers to design and fabrication of functional biodevice based on HNTs for tissue engineering, cancer diagnose/therapy, personal healthcare product.
- This article is part of the themed collection: Recent Review Articles