Prototype of Implant for Nitric Oxide Release Controlled by Infrared Radiation in Therapeutic Window.

Local therapeutic action and targeted drug release are promising approaches compared to traditional systemic drug administration. This is especially relevant for nitric oxide (NO), as its effects change dramatically depending on concentration and cellular context. Materials capable of releasing NO in deep tissues in a controlled manner might open new therapeutic opportunities. Light-sensitive NO donors represent a fascinating class of compounds with significant potential for precise and controlled NO release. However, most of them are sensitive to visible light, with only a few examples absorbing in a near-infrared therapeutic window. Here, we present the proof-of-concept of soft implants consisting of the photon upconverting core and the outer shell loaded with visible-light triggered NO donor. The separation into two compartments results in efficient energy harvesting by the dye and effective NO release under 980 nm infrared irradiation. Such implants could be used in smart therapies implying well-controlled and localized NO release.