Medical Microbots

As people age, one common problem is joint pain which can happen when the cartilage cushioning between bones degenerate. It's called osteoarthritis. One treatment focus is stem cells.

A study isolated mesenchymal stem cells from a person's fat tissue and bone marrow and injected them into the knee where the cartilage was damaged. The problem was the stem cells did not stay in the knee joint. That's when researchers began experimenting with microbots, microscopic 'machines' to deliver the cells that repair damage.

The microbots look like a soccer ball minus the panels, just the lattice that allows stem cells to enter. The spheres are coated with a magnetic chemical and with chitosan which is derived from shellfish. Both are nontoxic. The idea is for a surgeon to inject these magnetic spherical microbots into an injured knee.

The microbots equipped with cell generating stem cells are held in place with magnets attached to the outside of the knee over the injury site. It's ingenious! Over time the cells attach to the injury site and grow to repair the cartilage. The spheres are eventually biodegraded and removed from the body.

In experiments with rabbits, the microbots stayed in place for three weeks and significantly healed the animal's knee. Researchers are preparing for human trials and it looks rather promising. That would alleviate the acute pain of osteoarthritis for millions of Americans.