Technology has provided the medical sector with ever more accurate ways of investigating what is going on in our bodies. Radiography, TAC, MRI, fMRI and more let doctors look inside our bodies to see what's there and also how a given organ or tissue is actually working. Sensors on the body can track over shorter and longer periods some specific functions (like an Holter ECG monitoring heart beat through a day).
Now technology is moving one step ahead to provide sensors that can be embedded in our body.
This is the case pointed out by work being done at NIST and NIH in the US.
Scientists have developed tiny particles, in the 0.5-2µm range, that can work as sensors. Their size makes it possible to insert them in the body (and according to the scientists the size can be further shrunk down to 100nm).
The peculiarity of these particles is that they can change their shape in presence of different "chemical" conditions, such as changes in the Ph and ions concentration. These changes are associated to anomalies in the physiology and metabolisms and in turns are connected to specific diseases. As an example the Ph around cancer cells is slightly lower than around other cells. These differences cannot be detected by an analyses of the blood Ph since that mixes blood cells coming from various parts of the body.
Each particle, called GEMs, Geometrical Encoded Magnetic Sensors, consists of two magnetic discs separated by an hydrogel. The discs are 5 to 10 times smaller than a red blood cell, one of the smallest cells in our body, and the hydrogel separates the discs by a few nm. As chemical conditions changes the hydrogel absorbs more or less water hence increasing or decreasing the distance between the discs. These changes can be accurately measured through MRI. The GEMs are injected in the blood stream and the person can be subject to several monitoring sessions to first detect anomalies and identify diseases and than to monitor the effect of the cure.
GEMs can be configured to respond, be sensitive, to different conditions. In practice this means to change the characteristics of the hydrogel. Each of these "breeds" of GEMs will generate its own fingerprint hence doctors will be able to detect several parameters at once. This represents another area of research: find different kinds of hydrogels to respond to different parameters, including temperature, oxygen, enzymes,...
We are not, yet, at the clinical stage but it shouldn't be long before we will share our bodies with these kinds of particles, a sort of black box that will continuously provide information to our doctors.