Film delivers drugs

A new thin-film coating developed at MIT can deliver controlled drug doses to specific targets in the body following implantation, essentially serving as a 'micro pharmacy.'

The film could eventually be used to deliver drugs for cancer, epilepsy, diabetes and other diseases. It is among the first drug-delivery coatings that can be remotely activated by applying a small electric field.

'You can mete out what is needed, exactly when it's needed, in a systematic fashion,' said Paula Hammond, the MIT Bayer Professor of Chemical Engineering.

The film, which is typically about 150 nanometres thick, can be implanted in specific parts of the body.

The films are made from alternating layers of two materials: a negatively charged pigment and a positively charged drug molecule, or a neutral drug wrapped in a positively charged molecule.

The pigment, called Prussian Blue, sandwiches the drug molecules and holds them in place. Part of the reason the researchers chose to work with Prussian Blue is that the US Food and Drug Administration (FDA) has already found it safe for use in humans.