Enhancing Antifungal Activity of Nitric Oxide-Releasing Polymers via the Incorporation of Piperine.

As hospital-acquired infections and antibiotic and antifungal resistance increase, there is a need for constant innovation of novel antimicrobial solutions. To this end, the endogenous free-radical gas nitric oxide has been explored, as nitric oxide kills bacteria effectively at low levels without producing significant cytotoxic effects. Biomaterials can be designed to release nitric oxide by incorporating nitric oxide donor molecules such as S-nitrosothiols. Though nitric-oxide-releasing materials show excellent cytocompatibility and antibacterial activity, their efficacy against fungal species is limited. This work aims to combine nitric oxide release via an S-nitrosothiol, S-nitroso-N-acetylpenicillamine, with the release of a natural antifungal compound, piperine, from a commercially available biomedical polymer, CarboSil. In this work, a polymer platform was successfully developed that does not induce cytotoxicity while causing statistically significant reductions in the adhered and planktonic microbial loads of two bacterial strains and one fungal strain. This material is promising for preventing hospital-acquired and biomaterial-associated infections in short-term applications.