Pharmacy-on-a-chip: the prototype is ready
Implantable "pharmacies-on-a-chip" will be able to allocate medications as needed, and not when the patient remembers about the pills. A prototype of such a device was developed by nanotechnologists at the Massachusetts Institute of Technology under the leadership of Professor Paula Hammond. The results of their work are published in PNAS on 11.02.2008.
The chip is a 150 nm thick film consisting of alternating layers of negatively charged pigment – Prussian blue (the choice is partly due to the fact that the FDA considers this dye safe for humans) and drug molecules – positively charged or neutral, attached to positively charged carrier molecules.
Under the influence of an external electric field, the pigment layers lose their charge and cease to hold the drug molecules, allowing them to dissolve in the environment. By adjusting the parameters of the field, you can accurately adjust the dosage and release rate of drugs.
It is not necessary to visit a doctor to adjust the operation of a pharmacy-on-a-chip. The external device will be able to turn on the electric field both by radio signal and automatically, at the command of the analyzer – for example, in response to an increase in blood glucose levels in diabetes mellitus. Such implants can also be implanted in the place from where the tumor was removed, and they will automatically release anti-cancer drugs if they "feel" that protein markers of a recurrent neoplasm have appeared in the environment.
So far, scientists have produced only prototypes of "pharmacy-on-a-chip" and demonstrated that when an external electric field is turned on, they release negatively charged molecules. Now the researchers plan to develop a working model of an implant loaded with a drug and conduct animal trials. If successful, in five years it will be possible to move on to clinical trials.