Nitric oxide photocaging platinum nanoparticles with anticancer potential

In this contribution we report the design, fabrication and properties of hydrosoluble platinum nanoparticles decorated with a nitric oxide (NO) caging compound. Direct monitoring of NO through an ultrasensitive NO electrode demonstrate that the nanoparticles are stable in the dark but supply NO at nanomolar levels exclusively upon light excitation. The biocompatibility of these nanohybrid systems and their potential in photoactivated anticancer therapy have been explored by in vitro experiments using tumor cell lines. Overall these nanoparticles meet a combination of ideal prerequisites in the context of biomedical applications. Indeed, they associate small sizes, good water solubility and thermal stability under physiological conditions with excellent biocompatibility and appreciable tumor cell mortality upon irradiation with visible light. All these features make our photoactivable nanoparticles very appealing point sources of NO from the viewpoint of practical application in the emerging field of nanomedicine.