German scientists have created specialized bandages and plasters that has a dye to monitor changes in the body's pH levels and reveal on how the wound underneath is getting healed.

The hi-tech dressing changes color from yellow to purple if the infection in the wound exists. Small injuries heal fast, but big wound takes time to heal and the infection could remain long. Scientists say doctors can now analyze how the wound is healing through the color change, instead of removing the plaster and checking the wound.

"We have developed an indicator dye which reacts to different pH values, and we have integrated it into a dressing and a plaster," Dr Sabine Trupp. "Healthy skin and healed wounds usually show a pH value of below five. If this value increases, it is shifting from the acid to the alkaline range, which indicates complications in the healing of the wound."

The special dressing is created by scientists at the Fraunhofer Research Institution for Modular Solid State Technologies EMFT in Germany. The initial tests of the dressing has been successful and further tests will be done at the University of Regensburg’s dermatology clinic.'The dye has to remain chemically stable when bonded to the fibers of the dressing material or the plaster to ensure that it does not get into the wound,' Dr Trupp said.