Photoactive drug delivery system offers promise

A new drug dosing system controlled by light has been developed by scientists at Queen's University Belfast.

The system may allow a drug to deliver drugs in the exact doses required to targeted areas of the body at targeted times. Combined, this delivery pattern could maximise a drug's therapeutic effect and reduce side effects and damage to healthy areas of the body.

Dr Colin P McCoy and colleagues from the School of Pharmacy at Queen's described their molecular-scale dosing devices as a new paradigm for precise control of drug dosing using light.

The devices consist of medications combined with chemical compounds which respond to light in ways which release precisely controlled amounts of the drug. Drug release begins when light falls on the compounds and lasts only as long as the light is applied.

McCoy's study, which is reported in the Journal of the American Chemical Society, showed successful laboratory tests of the system in the controlled release of the anti-inflammatories aspirin, ibuprofen and ketoprofen.
Dr McCoy said of the technique: "One potential use we cited in the study would be in the treatment of urinary catheter infections, where the drug is held latently in the catheter, and is released when needed using light from a fibre optic. The system could likewise be used for other conditions using an implant under the skin for precisely controlled drug dosing."