Cancer is a universal issue which affects many people around the world. Many will turn to surgery in the hope a surgeon will be able to completely remove a tumor, leaving healthy tissues unaffected. Various tools and techniques have been developed over the years to improve the way these surgeries are performed, and visual imaging methods such as glowing dyes have proven to be very useful.

But one drawback is that some probes can also be activated in healthy tissues by endogenous enzymes, creating background fluorescence and making it harder to judge what should be removed. The opposite is also possible, where cancer cells are left unmarked and are missed during surgery, increasing the chance of recurrence.