Background Nitric oxide (NO) plays a critical role in wound healing, including stimulating vasodilation, angiogenesis and broad antimicrobial activity.

Aim To determine if acidified nitrite foam (ANF) is effective at killing microbial pathogens.

Methods A novel method to generate and deliver NO gas at the point of care was developed using acidified nitrite in a bubble foam. Using an ex vivo porcine dermal tissue model, the ANF was tested against six common microbial wound pathogens – Acinetobacter baumannii, Candida albicans, Pseudomonas aeruginosa, Proteus mirabilis, Staphylococcus aureus and Staphylococcus epidermidis. The prevention study tested the ANF against pathogens in the planktonic phenotype. The eradication study tested ANF against pathogens in the mature biofilm phenotype.

Results In the prevention study, a single 5-minute exposure of ANF prevented 4.5-log₁₀ to 8.6-log₁₀ growth of biofilms among the six tested pathogens. In the eradication study, a single 5-minute exposure of ANF generated a 1.2-log₁₀ to 2.5-log₁₀ reduction of mature biofilms among the six tested pathogens. In the same eradication study, two 5-minute topical exposures of the ANF separated by 10 minutes generated a 2.2-log₁₀ to 4.5-log₁₀ reduction.

Conclusions These study results suggest that a single treatment with ANF may be able to prevent biofilm reformation in chronic wounds and may eradicate some mature biofilms following two exposures.

Implications for clinical practice ANF is an effective antimicrobial agent against several tested biofilms and has the potential to become a preferred treatment in the fight against wound infection.