The multiple roles nitric oxide (NO) plays as a bioregulatory, anticancer, antimicrobial and antioxidant agent has triggered an explosive interest in recent years in compounds able to deliver this diatomic radical for therapeutic purposes. A major issue associated with NO donors is the precise control of the NO release, which effect is highly concentration and flux dependent. Light represents a convenient non-invasive on/off trigger to deliver NO on demand since it allows the accurate control of site, timing and dosage. The assembling of NO photodonors through different approaches may lead to intriguing light-responsive molecular constructs including nanostructured films, polymers, gels, nanoparticles and molecular conjugates which exhibit promising potential in view of practical applications. This tutorial review illustrates the recent research from our and other laboratories towards the fabrication of these molecular assemblies, highlighting the logical design and the relevance in the biomedical field. Therefore, this review is aimed to be a source of inspiration for a wide range of scientists belonging to the chemical, materials science and biochemical communities, facing the common challenge of fabricating controllable NO dispensers.

The achievement of nanomaterials able to release therapeutic agents in a controlled fashion is a major challenge in the burgeoning field of nanomedicine. Light represents the most elegant and non-invasive trigger to deliver bio-active compounds on demand since it allows the accurate control of three key factors determining the therapeutic outcome including site, timing and dosage. Recent breakthroughs in nanotechnology offer the opportunity to characterize, manipulate and organize matter at the nanometre scale, controlling the size and shape of the resulting nanomaterials and greatly improving the biocompatibility and the cellular uptake efficiency. This feature article illustrates some recent advances in the fabrication of light-triggered nanomaterials for biomedical delivery, describing representative examples from our laboratory and others, underlying the logical design and highlighting the potential applications in some major areas such as drug and gene release, photodynamic and photothermal therapy.