Cell killer

A US engineer has developed a laser 'microscalpel' that destroys single cells while leaving nearby cells intact.
 
If commercialised, such a system would enable surgeons to remove a cancerous cell with high precision without damaging the cells above and below it while viewing the procedure while it was underway.

The system itself is built around a femtosecond laser that produces extremely brief, high-energy light pulses that sear a targeted cell so quickly and accurately the lasers’ heat has no time to escape and damage nearby healthy cells.

It includes a tiny, flexible probe that focuses the light pulses to a spot size smaller than human cells. Within a few years, mechanical engineering Assistant Professor Adela Ben-Yakar at the University of Texas at Austin expects to shrink the probe’s 15mm diameter three-fold, so it would match the size of the endoscopes used today for laparoscopic surgery.

Ben-Yakar is also investigating the use of nanoparticles to focus the light energy on targeted cells. Last year, she demonstrated that gold nanoparticles can function as nano-scale magnifying lenses, increasing the laser light reaching cells by at least ten fold.

'If we can consistently deliver nanoparticles to cancer cells or other tissue that we want to target, we would be able to remove hundreds of unwanted cells at once using a single femtosecond laser pulse,' Ben-Yakar said. 'But we would still be keeping the healthy cells alive while photo-damaging just the cells we want, basically creating nanoscale holes in a tissue.'