Topical photochemical nitric oxide release from porous poly(vinyl alcohol) membrane for visible light modulation of dermal vasodilation

Abstract

Abstract Complications of functional peripheral artery disease (PAD), like chronic wounds and Raynaud’s disease and phenomenon, have stimulated the development of topical nitric oxide (NO)-releasing biomaterials capable of restoring the blood flow locally. In this work, we used phase inversion technique to prepare porous membranes of poly(vinyl alcohol) (PVA) functionalized with NO-releasing S-nitrosothiol (SNO) moieties. This strategy led to crosslinked amorphous membranes with swelling degree of 750 wt% and interconnected macropores with diameters greater than 600 μm. Controlling the extent of the S-nitrosation reaction allowed obtaining PVA-SNO membranes that spontaneously release NO in the range of 33–53 nmol/cm 2 in the dark. Irradiation of these membranes with visible light, led to first order NO release kinetics with rate constant of (5.6 ± 0.2) × 10 −3 s −1 and increased the amount of NO released to 64–101 nmol/cm 2 . Topical application of PVA-SNO membrane for 4 min on the healthy skin, led to a fast and localized 300% increase in the dermal blood flow, which was enhanced to 900% when the membrane was irradiated with visible light, during the same period. These results show that the photochemical NO release from macroporous PVA-SNO membrane is an effective tool for modulating NO actions in the treatment/prevention of PAD symptoms and other biomedical applications.