Researchers Deploy Light-Heated Water to Stimulate Drug Delivery

3 April 2014
A new method for using light to stimulate drug-delivering nanoparticles in the human body, recently developed by US researchers, offers promising potential for a variety of industrial, medical and scientific applications.
The technique is a result of work by researchers from the University of California, San Diego Skaggs School of Pharmacy and Pharmaceutical Sciences, helped by materials scientists, engineers and neurobiologists. It uses near-infrared (NIR) light from a low-power laser to heat up pockets of water situated within polymeric nanoparticles infused with drugs that are non-photo responsive. The light is absorbed by the water pockets as heat that makes the encapsulating polymer softer and lets the drug be released into the surrounding tissue. The process can be performed several times, the researchers.
The mechanism, which is compatible with nearly all types of polymer, employs NIR at a vibrational wavelength with the purpose of exciting water molecules that absorb the optical energy and turn it into heat. NIR is known for its quality to filter through biological tissues deeper than visible or ultraviolet light.
Thanks to the integration of hydrated polymers and near-infrared light, the method successfully overcomes certain technological and health limitations encountered in previous approaches, according to the scientists. Earlier attempts to deploy NIR-triggered release have not been much exploited chiefly due to to need for special designer polymers, costly high-powered lasers and/or the use of non-organic material with uncertain impact on safety in the body.