The application of various magnetic fields for boosting the efficacy of different antimicrobial molecules or in the character of a self-reliant antimicrobial agent is considered a promising approach to eradicating bacterial biofilm-related infections. The purpose of this study was to analyze the phenomenon of increased activity of octenidine dihydrochloride-based antiseptic (OCT) against Staphylococcus aureus and Pseudomonas aeruginosa biofilms in the presence of the rotating magnetic field (RMF) of two frequencies, 5 and 50 Hz, in the in vitro model consisting of stacked agar discs, placed in increasing distance from the source of the antiseptic solution. The biofilm-forming cells' viability and morphology as well as biofilm matrix structure and composition were analyzed. Also, octenidine dihydrochloride permeability through biofilm and porous agar obstacles was determined for the RMF-exposed versus unexposed settings. The exposure to RMF or OCT apart did not lead to biofilm destruction, contrary to the setting in which these two agents were used together. The performed analyses revealed the effect of RMF not only on biofilms (weakening of cell wall/membranes, disturbed morphology of cells, altered biofilm matrix porosity, and composition) but also on its milieu (altered penetrability of octenidine dihydrochloride through biofilm/agar obstacles). Our results suggest that the combination of RMF and OCT can be particularly promising in eradicating biofilms located in such areas as wound pockets, where physical obstacles limit antiseptic activity.

Chronic wound infection is highly associated with morbidity and endangers the patient's life. Therefore, wound care products must have a potent antimicrobial and biofilm-eradicating effect. In this work, the antimicrobial/antibiofilm activity of two low-concentrated chlorine-based and releasing solutions was investigated on a total of 78 strains of methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans, using the cohesive spectrum of in vitro settings, including microtiter plate models, biofilm-oriented antiseptic test, cellulose-based biofilm model, biofilm bioreactors and Bioflux model. The antiseptic containing polyhexamethylene biguanide was used in the character of usability control of performed tests. The results obtained by static biofilm models indicate that low-concentrated chlorine-based and releasing solutions display none to moderate antibiofilm activity, while data obtained by means of the Bioflux model, providing flow conditions, indicate the moderate antibiofilm activity of substances compared with the polyhexanide antiseptic. Considering in vitro data presented in this manuscript, the earlier reported favorable clinical results of low-concentrated hypochlorites should be considered rather an effect of their rinsing activity combined with low cytotoxicity but not the antimicrobial effect per se. For the treatment of heavily biofilm-infected wounds, polyhexanide should be considered the agent of choice because of its higher efficacy against pathogenic biofilms.