Research scientists at Queen Mary, University of London have developed a new variety of microcapsules capable of storing pharmaceutical chemicals in the body for later release. These so called “micro shuttles” have the potential to be smart enough to release their payload only when certain conditions are present in the body. An example would be high blood glucose levels which would trigger opening of insulin carrying capsules, bringing a new level of safety to diabetic patients.
The capsules, which have a diameter of two micrometers (about the size of a bacterium), are built by wrapping strands of a metabolism-resistant material around spherical particles, which are then dissolved in acid, leaving behind an empty container.
To fill the capsules, the scientists heat them in a solution that contains the desired drug compound. This makes them shrink and traps some of the solution and compound inside.
The loaded capsules are introduced into live cells by a technique known as electroporation – a tiny electric shock – which makes the cell walls permeable for micrometer-sized particles. The cells are unharmed by this treatment and retain the capsules.
In this experiment, the capsules were exposed to an infra-red laser beam that does not affect the cell but is picked up by nano-gold particles in the capsule walls, changing their structure and releasing the micro shuttle contents.
Press release: ‘Micro shuttle’ drug delivery could mean an end to regular dosing …
Abstract in Small: Intracellular transport…
