Molecular 'hats' disguise peptides until activated with UV light at a target

Lead researcher Andrés García

Introducing biomaterials such as peptides into the body often leads to an immune response that, in an effort to protect the body from foreign substances, can render the biomaterial useless. Normally, this is a necessary function, but when that biomaterial is a drug devoted to a higher purpose, this process can be a hindrance to successful treatment.

Researchers at the Georgia Institute of Technology have found a way to sneak peptides past the immune system by fitting them with cages that cover binding sites on the proteins like a hat, according to the university. These prevent the binding sites from revealing the peptides' true nature as something from the outside.

Included in the design of these cages is the ability to disengage when shone with an ultraviolet light. Thus, when the vehicles reach their targets with the drugs, a light shone through the skin to a specific target will allow them to become active at that particular place.

This is the first time a team has used biological signals activated by light for this purpose, according to the report.

"Many biological processes involve complex cascades of reactions in which the timing must be very tightly controlled," lead investigator Andrés García said in a statement. "Until now, we haven't had control over the sequence of events in the response to implanted materials. But with this technique, we can deliver a drug or particle with its signal in the 'off' position, then use light to turn the signal 'on' precisely when needed."

Down the road, the scientists hope to make different hats that respond to different wavelengths of light, offering even more control and a more complex treatment process.

- here's the Georgia Tech report