Fabrication of nanobeads from nanocups by controlling scission/crosslinking in organic polymer materials

Development of Advanced Biodevices Using Quantum Beam Microfabrication Technology

Biodevices with engineered micro- and nanostructures are strongly needed for advancements in medical technology such as regenerative medicine, drug discovery, diagnostic reagents, and drug delivery to secure high quality of life. The authors produced functional biocompatible plastics and hydrogels with physical and chemical properties and surface microscopic shapes that can be freely controlled in three dimensions during the production process using the superior properties of quantum beams. Nanostructures on a biocompatible poly(L-lactic acid) surface were fabricated using a focused ion beam. Soft hydrogels based on polysaccharides were micro-fabricated using a focused proton beam. Gelatin hydrogels were fabricated using γ-rays and electron beam, and their microstructures and stiffnesses were controlled for biological applications. HeLa cells proliferated three-dimensionally on the radiation-crosslinked gelatin hydrogels and, furthermore, their shapes can be controlled by the micro-fabricated surface of the hydrogel. Long-lasting hydrophilic concave structures were fabricated on the surface of silicone by radiation-induced crosslinking and oxidation. The demonstrated advanced biodevices have potential applications in three-dimensional cell culture, gene expression control, stem cell differentiation induction/suppression, cell aggregation into arbitrary shapes, tissue culture, and individual diagnosis in the medical field.

Peroxidase-mediated biodegradation of carbon nanotubes in vitro and in vivo

As a result of their unique electronic, optical, and mechanical properties, carbon nanotubes (CNTs) have been implemented in therapeutic and imaging applications. In an idealized situation, CNTs would be disposed of after they transport their theranostic payloads. Biodegradation represents an attractive pathway for the elimination of CNT carriers post-delivery and may be integral in catalyzing the release of the cargo from the delivery vehicle. Accordingly, recent research efforts have focused on peroxidase-driven biodegradation of CNTs. In this review, we not only summarize recent efforts to biodegrade CNTs in the test tube, in vitro, and in vivo, but also attempt to explore the fundamental parameters underlying degradation. Encouraged by the in vivo results obtained to date, we envision a future, where carbon-based nano-containers, which are specifically designed to target organs/cells, deliver their cargo, and biodegrade via peroxidase-driven mechanism, will represent an attractive therapeutic delivery option in nanomedicine.