Gradient Photothermal Field for Precisely Directing Cell Sheet Detachment.

Due to the remaining intact intercellular interactions, cell sheets play increasing roles in biomedical fields. Recently, spatiotemporal control of cell sheets has become an urgent requirement in the context of precise surgery. Here, the development of a gradient photothermal biointerface for precisely directing cell sheet detachment through quantitatively regulating the dissociation rate of collagen is reported. This novel and facile method shows great potential for application in precise regenerative medicine.

Designing 3D Biological Surfaces via the Breath-Figure Method.

The fabrication of biointerfaces that mimic cellular physiological environments is critical to understanding cell behaviors in vitro and for the design of tissue engineering. Breath figure is a self-assemble method that uses water droplets condensed from moisture as template and ends up with a highly ordered hexagonal pore array; this approach is used to fabricate various biological substrates. This progress report provides an overview of strategies to achieve topographical modifications and chemical-patterned arrays, such as modulation of the pore size, shape and selective decoration of the honeycomb holes. Using recent results in the biological fields, potential future applications and developments of honeycomb structures are commented upon.

Stepwise growth of gold coated cancer targeting carbon nanotubes for the precise delivery of doxorubicin combined with photothermal therapy.

Combining doxorubicin with thermal therapy in the clinic has led to startling results in the treatment of problematic cancers. Here, we describe a multimodal multi-walled carbon nanotube material that combines tumor targeting, doxorubicin delivery, and photothermal therapy for localized cancer treatment. The agent was constructed layer-by-layer from polypyrrole and gold nanoparticles on multi-walled carbon nanotubes. The gold surface was modified with tumor targeting folic acid terminated PEGylated chains, which also provide water-dispersibility, biocompatibility and should extend the half-life in blood. The material has a high loading/unloading capacity for the cytotoxic agent doxorubicin. Release of the doxorubicin, combined with the photothermal properties of the material that induces localized hyperthermia, leads to efficient cancer cell death.