At IEEE MEMS 2013, an international academic conference that took place in January 2013, one of the announcements about innovative medical technologies was about the development of a MEMS device having a DDS (drug delivery system) function to supply a drug solution to eyeball tissues (thesis number: 1-1).
The device is attached to the back side of an eyeball (the unexposed side). It is not equipped with a power supply or actuator but can be remotely controlled by using a magnetic field to control the dosage of drug. It is aimed at treating a disease that increases the number of blood vessels of the retina too much due to diabetes and causes sight loss.
The MEMS device is made mainly of a resin (PDMS: polydimethylsiloxane). It consists of a tank for storing the drug solution and a lid made by using a thin film that contains a magnetic material. Because the lid has a guiding structure that fits the curved surface of an eyeball, the device can be closely attached to the eyeball.
When a magnetic field is applied to the device from outside the human body, the thin film is bent and the drug solution in the tank is ejected. By controlling the strength of the magnetic field, it is possible to supply any dosage of drug at any time.
This time, a prototype of the device was made, and its operations were tested by using a human eyeball provided by a donor. And it was confirmed that a drug solution can be administered at any time by applying a magnetic field in a pulsed way and its amount can be controlled to a certain degree.
According to the University of California, Berkeley, which announced the device, it is still in the research phase and not in the phase where it can be co-developed with a company.