Nitric oxide (NO) releasing sol-gel materials coated with poly(vinyl chloride) (PVC) films exhibit increased stability at ambient and physiological temperatures. The polymer overcoat, however, reduces the NO fluxes by 5-35% over the initial week of release. The variation in NO fluxes between unmodified and PVC-coated sol-gels is negligible after 7 days. The PVC polymeric layer provides controlled surface chemistry for systematic studies of the effects of NO release on bacterial adhesion. As an example, the adhesion of Pseudomonas aeruginosa and Proteus mirabilis at PVC-coated NO-releasing sol-gels is investigated. A direct NO dependence on the reduction of P. aeruginosa adhesion is observed for NO fluxes up to 20 pmol cm(-2) s(-1). Although decreased by 50% in the presence of NO release, P. mirabilis adhesion does not appear to correlate to the flux of NO release. PVC-coated NO-releasing sol-gels may prove useful for studying the effects of localized NO release on other biological and chemical systems.