Arizona State University physicists have developed a new laser technique which can destroy virii and bacteria without damaging human cells. It is hoped that the laser can be adapted for use in stopping hospital infections such as MRSA.

The technique uses an infrared laser that is fine-tuned so that is can discriminate between human cells and micro-organisms. Femto-second laser pulses are used to produce vibrations in the protein coat of the micro-organisms. This vibration disrupts the coat, killing the viruses and bacteria but does no damage to the surrounding tissue because the structural compositions of the cells and the micro-organisms are different.

Researchers are hoping that the laser may help in the disinfection of hospital supplies such as blood or biomaterials. There is also the potential to use the laser in the treatment of blood-borne diseases such as AIDS and hepatitis.