Nitric oxide-donating materials and their potential in pharmacological applications for site-specific nitric oxide delivery

The discovery of various regulatory, protective and deleterious effects of nitric oxide (NO) has prompted intense research activity in the design and synthesis of NO-donating drugs and materials that can be used to modulate the effective concentrations of NO at biological targets. To date, various NO-donating compounds have been incorporated or immobilized in biocompatible polymer matrices and such materials have been used as patches, wound dressings, coatings on blood-contacting medical devices and time-release NO drugs. Recently, attention has been drawn toward light-sensitive NO donors, such as S-nitrosothiols and metal nitrosyls, which can deliver NO at selected targets under the total control of light. The pharmacological potential of such NO-donating materials including those with immobilized photoactive NO donors are reviewed in this article.