In the not-too-distant future, wounds may be covered not just with regular bandages, but with special "microvascular stamps" that promote and direct the growth of new blood vessels. A team of scientists from the University of Illinois have already created such a dressing, which could ultimately have applications far beyond the healing of cuts.

The stamp measures approximately one centimeter across, and is made from layers of a hydrogel containing polyethylene glycol polymer and edible methacrylic alginate gelatin. Its other key ingredient, however, is living cells. These are said to release growth factors in a more sustained and targeted manner than has been possible with previous dressings that contained growth factors alone, without cells.

The growth factors are able to permeate the underside of the stamp through channels of various sizes. When the stamp was tested on the surface of a chicken embryo, the network of new blood vessels that formed after one week mirrored the pattern of those channels.

An obvious use for the stamp would be as a covering for wounds such as surgical incisions, which it would likely heal faster, with less scarring. The U Illinois researchers, however, also believe that it could serve to direct new blood vessels around blocked arteries, increase the blood flow in poorly-vascularized tissue, and "normalize" the blood vessels feeding a tumor, in order to improve the delivery of anti-cancer drugs.

A paper on the research is soon to be published in the journal Advanced Materials.