Nanocapsules bubble up

Japanese researchers have developed a technique for the production of silicon dioxide nanocapsules using tiny bubbles of carbon dioxide in a silicon copolymer.

Nanocapsules have very thin shells and diameters in the nanometre range. They hold a tiny volume of liquid and protect their cargo while transporting it through a foreign medium, such as in a human blood vessel, without any loss. Applications for nanocapsules include the delivery of medication and the encapsulation of scents, printer ink, and adhesives. Once at their destinations, the payloads are released by pressure or friction.

Lei Li and Hideaki Yokoyama, from Japan’s National Institute of Advanced Industrial Science and Technology, developed the new technique. They coated silicon wafers, which act as a support, with thin films of a plastic that consists of molecules with segments of different types of polymers. These are known as block copolymers, in this case made of polystyrene and silicone.